Resumo

Muitas vezes veremos dentre os modelos de machine learning, termos como LASSO regression e Ridge Regression; e, justamente essa que queremos exemplificar nesse breve tutorial. Esse método é sugerido como exemplo de solução da multicolinearidade, formulado inicialmente por Hoerl e Kennard (Hoerl e Kennard, 1977).

Reproduzimos aqui o mesmo exemplo apresentado em Maddala, p. 144-145 e 149-150, 2001.

Algumas estimativas podem ser diferentes provavelmente pelas omissões de detalhes a este respeito do próprio autor ou pelos métodos empregados pelo uso de diferentes softwares.


Introdução

Em linhas gerais, a idéia é adicionar uma constante \(\lambda\) às variâncias das variáveis explicativas antes de resolver as equações normais.

Vamos a um exemplo numérico para elucidar com mais clareza:


Exemplo ilustrativo

Veremos os impactos da multicolinearidade nos dados considerando o seguinte modelo:

\[ Y=\beta_{1}X_{1}+\beta_{2}X_{2}+u.\quad\mbox{Se}\,\,X_{2}+2X_{2},\,\,\mbox{temos} \] \[ Y=\beta_{1}X_{1}+\beta_{2}(2X_{1})+u=(\beta_{1}+2\beta_{2})X_{1}+u \] Logo, apenas (\(\beta_{1}+2\beta_{2}\)), poderia ser estimado. Não podemos achar estimativas de \(\beta_{1}\) e \(\beta_{2}\) separadamente. Nesse caso, dizemos que existe “multicolinearidade perfeita,” porque \(X_{1}\) e \(X_{2}\) são perfeitamente correlacionadas (com \(R^{2}=1\)). Na prática, encontramos casos onde \(R^{2}\) não é exatamente 1, mas próximo de 1.

Como ilustração, considere o caso no qual:

\(\quad \quad \quad \quad S_{11}=\sum X_{1i}^{2}-n\overline{X}_{1}^{2}=200 \quad \quad \quad \quad \quad S_{12}=\sum X_{1i}X_{2i}-n\overline{X}_{1}\overline{X}_{2}=150\)

\(\quad \quad \quad \quad S_{13}=\sum X_{2i}^{2}-n\overline{X}_{2}^{2}=113\)

\(\quad \quad \quad \quad S_{1Y}=\sum X_{1i}Y_{i}-n\overline{X}_{1}\overline{Y}=350 \quad \quad \quad S_{2Y}=\sum X_{2i}Y_{i}-n\overline{X}_{2}\overline{Y}=263\)

Assim, as equações normais são:

\(S_{1Y}=\widehat{\beta}S_{11}+\widehat{\beta_{2}}S_{12}\) e simplificando de modo similar temos:

\(S_{2Y}=\widehat{\beta}S_{11}+\widehat{\beta_{2}}S_{12}\) o que nos possibilita resolver essas duas equações para acharmos \(\widehat{\beta_{1}}\) e \(\widehat{\beta_{2}}\), obtemos

\[ \widehat{\beta_{1}}=\frac{S_{22}S_{1Y}-S_{12}S_{2Y}}{S_{11}S_{22}-S_{12}^{2}} \] e

\[ \widehat{\beta_{2}}=\frac{S_{11}S_{2Y}-S_{12}S_{1Y}}{S_{11}S_{22}-S_{12}^{2}} \]

e o intercepto, então:

\[ \widehat{\alpha}=\overline{Y}-\widehat{\beta_{1}}\overline{X}_{1}-\widehat{\beta_{2}}\overline{X}_{2} \]

Então substituindo os valores nas equações normais teremos:

\[ \quad \quad \,\,200\widehat{\beta}_{1}+150\widehat{\beta}_{2}=350\quad \quad \mbox{e,} \]

\[ 150\widehat{\beta}_{1}+113\widehat{\beta}_{2}=263 \]

Em linhas gerais, a idéia é adicionar uma constante \(\lambda\) às variâncias das variáveis explicativas antes de resolver essas equações normais. Em nosso exemplo citado acima, adicionamos 5 a \(S_{11}\) e \(S_{12}\). Vemos agora que o nosso coeficiente de determinação se reduz:

Então se tínhamos \(R^{2}=\frac{(150)^{2}}{200(113)}=0,995\) agora temos \(R^{2}=\frac{(150)^{2}}{205(118)}=0,930\)

Pode-se facilmente ver que se trata de uma solução mecânica simples. Contudo, há uma enorme literatura sobre a regressão ridge.

A adição de \(\lambda\) às variâncias produz estimadores tendenciosos, mas o argumento é que se a variância puder ser reduzida, o erro quadrático médio diminuirá. Hoerl e Kennard, 1977 mostram que sempre existe uma constante \(\lambda>0\) tal como

\[ \sum^{k}_{i=1}\mbox{EQM}(\widetilde{\beta}_{i})<\sum^{k}_{i=1}\mbox{EQM}(\widehat{\beta}_{i}) \]

onde \(\widetilde{\beta}_{i}\) são os estimadores de \(\beta_{i}\) da regressão ridge, \(\widehat{\beta}_{i}\) são os estimadores de MQO e \(k\), o número de regressores.

Infelizmente, \(\lambda\)1 é uma função dos parâmetros de regressão \(\beta_{i}\) e da variância de erro \(\sigma^{2}\), que é desconhecida. Hoerl e Kennard sugerem a tentativa de diferentes valores de \(\lambda\) e a escolha de um valor para \(\lambda\) de forma que “o sistema se estabilize” ou que os “coeficientes não tenham valores não-razoáveis”. Assim argumentos subjetivos são usados.

Alguns outros sugeriram a obtenção de estimativas iniciais de \(\beta_{i}\) e \(\sigma^{2}\) e, então, o uso do \(\lambda\) estimado. Esse procedimento pode ser iterado e acharemos estimadores ridge iterados. Trata-se de um modelo que tem sido questionado devido a sua suposta inutilidade.2

Um outro problema da regressão ridge é o fato de que ela não é invariante a unidades de medição das variáveis explicativas e a transformações lineares das variáveis. Se tivermos duas variáveis explicativas \(X_{1}\) e \(X_{2}\) e medirmos \(X_{1}\) em dezenas e \(X_{2}\) em milhares, não fará sentido adicionar o mesmo valor de \(\lambda\) à variância de ambas. Esse problema pode ser evitado normalizando cada variável dividindo-as por seus devidos padrões. Mesmo se \(X_{1}\) e \(X_{2}\) forem medidas nas mesmas unidades, em alguns casos há diferentes transformações lineares de \(X_{1}\) e \(X_{2}\) que são igualmente sensíveis. Conforme discutido as equações demonstradas acima são todas equivalentes e sensíveis. Os estimadores ridge, porém, diferirão dependendo de qual dessas formas é usada.

Existem diferentes situações sob as quais a regressão ridge surge naturalmente. Elas iluminarão o caso das circunstâncias sob as quais o método será útil. Mencionamos três delas.

  1. Mínimos quadrados restritos. Suponha que estimamos os coeficientes de regressão sujeitos à condição de que

\[ \sum^{k}_{i=1}\beta_{i}^{2}=c \]

então acharíamos algo como a regressão ridge. O \(\lambda\) que usamos é o multiplicador lagrangeano na minimização. Para ver isso, suponha que tenhamos duas variáveis explicativas.

Achamos os estimadores de mínimos quadrados restritos minimizando

\[ \sum (Y-\beta_{1}X_{1}-\beta_{2}X_{2})^{2}+\lambda(\beta_{1}^{2}+\beta_{2}^{2}-c) \]

onde \(\lambda\) é o multiplicador Lagrangeano. Diferenciando essa expressão com respeito a \(\beta_{1}\) e \(\beta_{2}\) e igualando as derivadas a zero, achamos as equações normais

\[ 2\sum (Y-\beta_{1}X_{1}-\beta_{2}X_{2})(-X_{1})+2\lambda \beta_{1}=0 \]

\[ 2\sum (Y-\beta_{1}X_{1}-\beta_{2}X_{2})(-X_{1})+2\lambda \beta_{2}=0 \]

Essas equações pode ser escritas como

\[ (S_{11}+\lambda)\beta_{1}+S_{12}\beta_{2}=S_{1Y} \] \[ S_{12}\beta_{1}+(S_{22}+\lambda)\beta_{2}=S_{2Y} \]

onde:

\(S_{11}=\sum X_{1}^{2},\quad \quad \quad S_{12}=\sum X_{1}X_{2}\) e

\(S_{22}=\sum X^{2}_{2i}-n\overline{X}^{2}_{2}\) assim por diante.

Portanto, achamos a regressão ridge e \(\lambda\) é o multiplicador Lagrangeano. O valor de \(\lambda\) é decidido pelo critério \(\beta_{1}^{2}\) e \(\beta_{2}^{2}=c\). Nesse caso, existe um atalho para se escolher \(\lambda\).

É raro o caso em que temos conhecimento a priori sobre \(\beta_{i}\) que esteja na forma \(\sum \beta_{i}^{2}=c\). Mas algumas outras informações menos concretas também podem ser usadas para se escolher o valor de \(\lambda\) na regressão ridge. A versão de Brown e Beattie3 na estimação da função de produção usa informações a priori sobre a relação entre os sinais dos \(\beta_{i}^{'}s\).

  1. Intepretação Bayesiana Não discutimos neste livro a abordagem Bayesiana à estatística. Contudo, grosso modo, o que tal abordagem faz é combinar sistematicamente algumas informações a priori sobre os parâmetros de regressão com informação amostral. Nessa abordagem, achamos as estimativas da regressão ridge dos \(\beta^{'}s\) se assumirmos que a informação a priori é da forma que \(\beta_{i}\sim IN(0,\sigma^{2}_{\beta})\). Nesse caso, a constante ridge \(\lambda\) é igual a \(\sigma^{2}/\sigma_{\beta}^{2}\). Novamente, \(\sigma^{2}\) não é conhecida mas tem que ser estimada. Entretanto, em quase todos os problemas sobre economia esse tipo de informação a priori (que as médias dos \(\beta^{'}s\) são zero) é muito pouco razoável. Isso sugere que um estimador ridge simples não faz sentido em econometria (com a interpretação Bayesiana). Obviamente, o pressuposto de que \(\beta_{i}\) tem média zero pode ser relaxado. Mas então acharemos estimadores mais complicados (estimadores ridge generalizados).

  2. Interpretação de medição de erros. Considere o modelo com duas variáveis que discutimos sob mínimos quadrados restritos. Suponha que adicionamos erros aleatórios com média zero e variância \(\lambda\) em \(X_{1}\) e \(X_{2}\). Como esses erros são aleatórios, a covariância entre \(X_{1}\) e \(X_{2}\) não será afetada. As variâncias de \(X_{1}\) e \(X_{2}\) aumentarão em \(\lambda\). Dessa forma, achamos o estimador de regressão ridge. Essa interpretação torna o estimador ridge um tanto quanto suspeito. Smith e Campbell4 resumem isso em uma frase da seguinte forma: “Use dados menos precisos e ache estimativas mais precisas possíveis.

Essas são situações nas quais a regressão ridge pode ser facilmente justificada. Em quase todos os outros casos, há julgamento subjetivo envolvido. Esse julgamento subjetivo é, muitas vezes, igualado à “informação a priori vaga”. Os métodos Bayesianos permitem uma análise sistemática dos dados com “informação a priori vaga” mais uma discussão desses modelos está além do escopo deste tutorial.

Por causa dessas deficiências da regressão ridge, o método não é recomendado como uma solução geral ao problema da multicolinearidade. Particularmente, a forma mais simples do método (onde uma constante \(\lambda\) é adicionada a cada variância) não é mais útil. Não obstante, à guisa de curiosidade, apresentaremos alguns resultados desse método.

A partir dessa tabela aqui no formato Excel, com base nos dados da função consumo estimamos a equação de regressão

#carrego os dados

library(readxl)

url<-"https://github.com/rhozon/Introdu-o-Econometria-com-Excel/blob/master/Maddala%20p.%20148.xlsx?raw=true"
dados <- tempfile()
download.file(url, dados, mode="wb")
dados<-read_excel(path = dados, sheet = 1)



library(knitr)
library(kableExtra)

kbl(cbind(dados)) %>%
  kable_paper() %>%
  scroll_box(width = "800px", height = "200px")
Ano_Trim L C Y
1952 I 182.7 220.0 238.1
1952 II 183.0 222.7 240.9
1952 III 184.4 223.8 245.8
1952 IV 187.0 230.2 248.8
1953 I 189.4 234.0 253.3
1953 II 192.2 236.2 256.1
1953 III 193.8 236.0 255.9
1953 IV 194.8 234.1 255.9
1954 I 197.3 233.4 254.4
1954 II 197.0 236.4 254.4
1954 III 200.3 239.0 257.0
1954 IV 204.2 243.2 260.9
1955 I 207.6 248.7 263.0
1955 II 209.4 253.7 271.5
1955 III 211.1 259.9 276.5
1955 IV 213.2 261.8 281.4
1956 I 214.1 263.2 282.0
1956 II 216.5 263.7 286.2
1956 III 217.3 263.4 287.7
1956 IV 217.3 266.9 291.0
1957 I 218.2 268.9 291.1
1957 II 218.5 270.4 294.6
1957 III 219.8 273.4 296.1
1957 IV 219.5 272.1 293.3
1958 I 220.5 268.9 291.3
1958 II 222.7 270.9 292.6
1958 III 255.0 274.4 299.9
1958 IV 299.4 278.7 302.1
1959 I 232.2 283.8 305.9
1959 II 235.2 289.7 312.5
1959 III 237.2 290.8 311.3
1959 IV 237.7 292.8 313.2
1960 I 238.0 295.4 325.5
1960 II 238.4 299.5 320.3
1960 III 240.1 298.6 321.0
1960 IV 243.3 299.6 320.1
1961 I 246.1 297.0 318.4
1961 II 250.0 301.6 324.8

Fonte: Maddala, p. 148, (2001). apud os dados são de Z. Griliches et al., “Notes on Estimated Aggregate Quartely Consumption Functions”. Econometrica, julho de 1962.

Caso queira rodar no R, segue o link da documentação do pacote para regressão ridge recomendado

\[ c_{t}=\beta_{0}Y_{t}+\beta_{1}Y_{t-1}+\beta_{2}Y_{t-2}+\ldots+\beta_{8}Y_{t-8}+u_{t} \]

Não é preciso dizer que os \(Y^{'}_{t}s\) são altamente intercorrelacionados. Os resultados são apresentados a seguir. Note que conforme \(\lambda\) aumenta , há uma suavização dos coeficientes e a estimativa de \(\beta_{0}\) diminui. Os coeficientes de MQO, obviamente são muito erráticos. Mas as estimativas de \(\beta_{0}\) (porção da renda corrente no consumo corrente) são implausivelmente baixas com a regressão ridge.

A elevação súbita dos coeficientes após o quinto trimestre também é algo muito implausível. Talvez possamos apenas estimar os efeitos somente acima de quatro períodos. As estimativas MQO são erráticas mesmo com quatro períodos. A computação das estimativas da regressão ridge com quatro períodos é apresentada como exercício para você reproduzir em seu Excel.

Ao simplesmente seguirmos o modelo de obtenção dos coeficientes propostos inicialmente no trabalho de Heoerl e Kennard 1970 e citado no trabalho seminal do prof. G. S. Maddala em 1974 p. 5, obtemos

\[ \widehat{\beta}=(X^{'}X^{-1})X^{'}y \] e o estimador modificado:

\[ \widehat{\beta}_{R}=(X^{'}X + kI)X^{'}y \]

Onde \(I\) é a matriz identidade dada por \((X^{'}X)(X^{'}X)^{-1}\)5 e a constante \(k\) faz o mesmo trabalho de \(0\geq\lambda\leq 1\). Se \(det(X^{'}X)\approx 0\) os estimadores de MQO serão sensíveis a uma série de erros, como coeficientes de regressão imprecisos ou não significativos (Kmenta, 1980), com sinal errado e espectro de autovalores não uniforme. Além disso, o método MQO, pode produzir altas variâncias de estimativas, grandes erros padrão e amplos intervalos de confiança. A qualidade e estabilidade do modelo ajustado pode ser questionável devido ao comportamento errático do MQO no caso de regressores são colineares.

Alguns pesquisadores podem tentar eliminar o(s) regressor(es) que causam o problema, removendo conscientemente eles do modelo. No entanto, este método pode destruir a utilidade do modelo por remover regressor(es) relevante(s) do modelo. Para controlar a variância e instabilidade das estimativas MQO, pode-se regularizar os coeficientes, com alguns métodos de regularização, como regressão ridge (RR), regressão de Liu, métodos de regressão Lasso etc., como alternativa ao MQO. Computacionalmente, RR suprime os efeitos da colinearidade e reduz a magnitude aparente da correlação entre regressores, a fim de obter estimativas mais estáveis dos coeficientes do que as estimativas de MQO e também melhora a precisão da previsão (ver Hoerl e Kennard, 1970a; Montgomery e Peck, 1982; Myers, 1986; Rawlings et al., 1998; Seber e Lee, 2003; Tripp, 1983, etc.).


Rodando uma regressão Ridge no Excel

Ao procedermos com o modelo matricial no software Microsoft Excel, obtemos os seguintes resultados:

Iniciaremos regredindo um modelo via MQO com a notação matricial normalmente no Excel. Na aba “Regressão Ridge” na primeira etapa calculamos:

\[ (X^{'}X) \]

 

 

Em seguida obtemos a inversa da matriz \((X^{'}X)\) ou seja, \((X^{'}X)^{-1}\):

 

 

Agora fazendo \(X^{'}y\)

 

 

E finalmente os coeficientes de MQO:

 

 

Então ao obtermos essas matrizes, agora calculamos a matriz identidade quando calculamos \((X^{'}X)(X^{'}X)^{-1}\)

 

 

Agora montamos a matriz que multiplica a constante \(\lambda\) pela identidade

 

 

Para então calcularmos \(X^{'}X+kI\)

 

 

Finalmente obtemos os coeficientes da regressão ridge

 

 

Confirmamos o que o autor (Maddala, 2001, p. 150) “Note que conforme \(\lambda\) aumenta há uma suavização dos coeficientes e o valor de \(\beta_{0}\) diminui.” Veja os valores das somas dos coeficientes dado os valores de \(\lambda\) que o autor usa:

 


Introdução a Regressão Ridge com o pacote lmridge do R

Resumo

O estimador de regressão ridge, é uma das alternativas comumente utilizadas ao convencional estimador de mínimos quadrados ordinários, evita os efeitos adversos nas situações em que existe algum considerável grau de multicolinearidade entre os regressores. Existem muitos pacotes de software disponíveis para estimativa de coeficientes de regressão ridge. No entanto, a maioria deles exibe métodos para estimar os parâmetros de viés ridge sem procedimentos de teste. O pacote lmridge mantido por Imdad Ullah Muhammad pode ser usado para estimar coeficientes ridge considerando uma gama de diferentes parâmetros de viéses existentes, para testar esses coeficientes com mais de 25 estatísticas relacionadas ridge, e para apresentar diferentes exibições gráficas dessas estatísticas.

Detecção da colinearidade

Diagnosticar a colinearidade é importante para muitos pesquisadores. Consiste em dois relacionados, mas separados elementos:

  1. detectar a existência de relação colinear entre os regressores e;

  2. avaliar o até que ponto esta relação degradou as estimativas dos parâmetros

Os diagnósticos mais sugeridos e amplamente utilizados: correlações de pares, fator inflacionário de variância (VIF) / tolerância (TOL) (Marquardt, 1970), valores próprios e autovetores (Kendall, 1957), CN & CI (Belsley et al., 1980; Chatterjee e Hadi, 2006; Maddala, 1988), método de Leamer (Greene, 2002), regra de Klein (Klein, 1962), os testes propostos por Farrar e Glauber (Farrar e Glauber, 1967), indicador vermelho (Kovács et al., 2005), VIF corrigido (Curto e Pinto, 2011) e as medidas de Theil (Theil, 1971), (ver também Imdadullah et al. (2016)). Todos esses diagnósticos medidas são implementadas no pacote R, mctest.

Em seguida, usamos o pacote lmridge para calcular os coeficientes para diferentes estatísticas relacionadas aos métodos de seleção do parâmetro de viés ridge. Para a escolha ideal do parâmetro de viés ridge, representações gráficas dos coeficientes ridge, valores VIF, critérios de validação cruzada (CV e GCV), ridge DF, RSS, PRESS, ISRM e escala m versus parâmetro de viés ridge usado são considerados. Além da representação gráfica do modelo critérios de seleção (AIC e BIC) de regressão de ridge versus ridge DF também são realizados.

Começamos rodando o modelo via MQO tradicional:

url<-"https://github.com/rhozon/Introdu-o-Econometria-com-Excel/blob/master/Maddala%20p.%20148.xlsx?raw=true"
dados <- tempfile()
download.file(url, dados, mode="wb")
dados<-read_excel(path = dados, sheet = 2)

kbl(cbind(dados)) %>%
  kable_paper() %>%
  scroll_box(width = "800px", height = "200px")
C Y Ylag1 Ylag2 Ylag3 Ylag4 Ylag5 Ylag6 Ylag7 Ylag8
233.4 254.4 255.9 255.9 256.1 253.3 248.8 245.8 240.9 238.1
236.4 254.4 254.4 255.9 255.9 256.1 253.3 248.8 245.8 240.9
239.0 257.0 254.4 254.4 255.9 255.9 256.1 253.3 248.8 245.8
243.2 260.9 257.0 254.4 254.4 255.9 255.9 256.1 253.3 248.8
248.7 263.0 260.9 257.0 254.4 254.4 255.9 255.9 256.1 253.3
253.7 271.5 263.0 260.9 257.0 254.4 254.4 255.9 255.9 256.1
259.9 276.5 271.5 263.0 260.9 257.0 254.4 254.4 255.9 255.9
261.8 281.4 276.5 271.5 263.0 260.9 257.0 254.4 254.4 255.9
263.2 282.0 281.4 276.5 271.5 263.0 260.9 257.0 254.4 254.4
263.7 286.2 282.0 281.4 276.5 271.5 263.0 260.9 257.0 254.4
263.4 287.7 286.2 282.0 281.4 276.5 271.5 263.0 260.9 257.0
266.9 291.0 287.7 286.2 282.0 281.4 276.5 271.5 263.0 260.9
268.9 291.1 291.0 287.7 286.2 282.0 281.4 276.5 271.5 263.0
270.4 294.6 291.1 291.0 287.7 286.2 282.0 281.4 276.5 271.5
273.4 296.1 294.6 291.1 291.0 287.7 286.2 282.0 281.4 276.5
272.1 293.3 296.1 294.6 291.1 291.0 287.7 286.2 282.0 281.4
268.9 291.3 293.3 296.1 294.6 291.1 291.0 287.7 286.2 282.0
270.9 292.6 291.3 293.3 296.1 294.6 291.1 291.0 287.7 286.2
274.4 299.9 292.6 291.3 293.3 296.1 294.6 291.1 291.0 287.7
278.7 302.1 299.9 292.6 291.3 293.3 296.1 294.6 291.1 291.0
283.8 305.9 302.1 299.9 292.6 291.3 293.3 296.1 294.6 291.1
289.7 312.5 305.9 302.1 299.9 292.6 291.3 293.3 296.1 294.6
290.8 311.3 312.5 305.9 302.1 299.9 292.6 291.3 293.3 296.1
292.8 313.2 311.3 312.5 305.9 302.1 299.9 292.6 291.3 293.3
295.4 325.5 313.2 311.3 312.5 305.9 302.1 299.9 292.6 291.3
299.5 320.3 325.5 313.2 311.3 312.5 305.9 302.1 299.9 292.6
298.6 321.0 320.3 325.5 313.2 311.3 312.5 305.9 302.1 299.9
299.6 320.1 321.0 320.3 325.5 313.2 311.3 312.5 305.9 302.1
297.0 318.4 320.1 321.0 320.3 325.5 313.2 311.3 312.5 305.9
301.6 324.8 318.4 320.1 321.0 320.3 325.5 313.2 311.3 312.5
mqo<-lm(C~.,data = dados)
summary(mqo)
## 
## Call:
## lm(formula = C ~ ., data = dados)
## 
## Residuals:
##     Min      1Q  Median      3Q     Max 
## -3.0100 -1.2734  0.1837  1.5004  2.9643 
## 
## Coefficients:
##              Estimate Std. Error t value Pr(>|t|)    
## (Intercept)  4.977927   5.231783   0.951    0.353    
## Y            0.561854   0.115303   4.873 9.21e-05 ***
## Ylag1        0.384485   0.153463   2.505    0.021 *  
## Ylag2        0.027832   0.153605   0.181    0.858    
## Ylag3       -0.009855   0.154040  -0.064    0.950    
## Ylag4       -0.222292   0.158558  -1.402    0.176    
## Ylag5        0.026269   0.159173   0.165    0.871    
## Ylag6       -0.223042   0.216616  -1.030    0.315    
## Ylag7        0.210524   0.251760   0.836    0.413    
## Ylag8        0.163613   0.164040   0.997    0.330    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 2.014 on 20 degrees of freedom
## Multiple R-squared:  0.993,  Adjusted R-squared:  0.9899 
## F-statistic: 316.4 on 9 and 20 DF,  p-value: < 2.2e-16

Agora vamos investigar os padrões de colinearidades

library(mctest)

mctest(mqo)
## 
## Call:
## omcdiag(mod = mod, Inter = TRUE, detr = detr, red = red, conf = conf, 
##     theil = theil, cn = cn)
## 
## 
## Overall Multicollinearity Diagnostics
## 
##                        MC Results detection
## Determinant |X'X|:         0.0000         1
## Farrar Chi-Square:       780.0597         1
## Red Indicator:             0.9631         1
## Sum of Lambda Inverse:   915.6656         1
## Theil's Method:            0.9515         1
## Condition Number:        815.0507         1
## 
## 1 --> COLLINEARITY is detected by the test 
## 0 --> COLLINEARITY is not detected by the test

Os resultados de todas as medidas de diagnóstico de colinearidade geral indicam a existência de colinearidade entre os regressor(es). Esses resultados não informam qual (is) regressor(es) são razões de colinearidade. As medidas de diagnóstico individuais de colinearidade podem ser obtidas através de:

imcdiag(mqo,all=TRUE)
## 
## Call:
## imcdiag(mod = mqo, all = TRUE)
## 
## 
## All Individual Multicollinearity Diagnostics in 0 or 1 
## 
##       VIF TOL Wi Fi Leamer CVIF Klein IND1 IND2
## Y       1   1  1  1      0    0     0    1    0
## Ylag1   1   1  1  1      0    0     0    1    1
## Ylag2   1   1  1  1      0    0     0    1    1
## Ylag3   1   1  1  1      0    0     0    1    1
## Ylag4   1   1  1  1      0    0     0    1    1
## Ylag5   1   1  1  1      0    0     0    1    1
## Ylag6   1   1  1  1      1    0     1    1    1
## Ylag7   1   1  1  1      1    0     1    1    1
## Ylag8   1   1  1  1      0    0     0    1    1
## 
## 1 --> COLLINEARITY is detected by the test 
## 0 --> COLLINEARITY is not detected by the test
## 
## Ylag2 , Ylag3 , Ylag4 , Ylag5 , Ylag6 , Ylag7 , Ylag8 , coefficient(s) are non-significant may be due to multicollinearity
## 
## R-square of y on all x: 0.993 
## 
## * use method argument to check which regressors may be the reason of collinearity
## ===================================

Os resultados da maioria dos diagnósticos de colinearidade individual sugerem que todos os regressores são a razão para colinearidade entre regressores. A última linha da saída da função imcdiag () sugere que o method argument da função deve ser usado para verificar quais regressores podem ser a razão da colinearidade entre diferentes regressores.

Rodando a regressão ridge no R

Como estamos utilizando os dados de exemplo de Maddala, 2001 p. 148 neste tutorial, definimos do seguinte modo o nosso modelo:

library(lmridge)

lambdas<-c(0,0.0002,0.0006,0.0010,0.0014,0.0020)

ridge<-lmridge(C~.,dados,K=lambdas,scaling="sc")
summary(ridge)
## 
## Call:
## lmridge.default(formula = C ~ ., data = dados, K = lambdas, scaling = "sc")
## 
## 
## Coefficients: for Ridge parameter K= 0 
##              Estimate Estimate (Sc) StdErr (Sc) t-value (Sc) Pr(>|t|)    
## Intercept      4.9779   -31023.1365  16805.9650      -1.8460   0.0798 .  
## Y              0.5618       65.7313     13.1642       4.9932   0.0001 ***
## Ylag1          0.3845       45.3945     17.6822       2.5672   0.0184 *  
## Ylag2          0.0278        3.3277     17.9228       0.1857   0.8546    
## Ylag3         -0.0099       -1.1772     17.9564      -0.0656   0.9484    
## Ylag4         -0.2223      -26.3680     18.3547      -1.4366   0.1663    
## Ylag5          0.0263        3.0973     18.3153       0.1691   0.8674    
## Ylag6         -0.2230      -25.5644     24.2295      -1.0551   0.3040    
## Ylag7          0.2105       24.2975     28.3564       0.8569   0.4017    
## Ylag8          0.1636       19.0066     18.5971       1.0220   0.3190    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Ridge Summary
##        R2    adj-R2  DF ridge         F       AIC       BIC 
##   0.99300   0.99040   9.00002 332.26686  47.85786 162.50459 
## Ridge minimum MSE= 2032.758 at K= 0.002 
## P-value for F-test ( 9.00002 , 20.99994 ) = 1.398956e-20 
## -------------------------------------------------------------------
## 
## 
## Coefficients: for Ridge parameter K= 2e-04 
##              Estimate Estimate (Sc) StdErr (Sc) t-value (Sc) Pr(>|t|)    
## Intercept      4.9853   -31019.1039  16101.2473      -1.9265   0.0682 .  
## Y              0.5601       65.5308     12.8883       5.0845   0.0001 ***
## Ylag1          0.3838       45.3114     17.1640       2.6399   0.0156 *  
## Ylag2          0.0299        3.5739     17.4572       0.2047   0.8398    
## Ylag3         -0.0126       -1.5107     17.4860      -0.0864   0.9320    
## Ylag4         -0.2172      -25.7661     17.8030      -1.4473   0.1632    
## Ylag5          0.0203        2.3875     17.7348       0.1346   0.8942    
## Ylag6         -0.2122      -24.3265     22.9483      -1.0601   0.3016    
## Ylag7          0.1994       23.0131     26.4801       0.8691   0.3950    
## Ylag8          0.1681       19.5251     17.7249       1.1016   0.2836    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Ridge Summary
##        R2    adj-R2  DF ridge         F       AIC       BIC 
##   0.99270   0.99000   8.82469 332.31699  47.51329 161.91434 
## Ridge minimum MSE= 2032.758 at K= 0.002 
## P-value for F-test ( 8.82469 , 21.00737 ) = 1.510331e-20 
## -------------------------------------------------------------------
## 
## 
## Coefficients: for Ridge parameter K= 6e-04 
##              Estimate Estimate (Sc) StdErr (Sc) t-value (Sc) Pr(>|t|)    
## Intercept      5.0064   -31011.5895  14922.6564      -2.0782   0.0505 .  
## Y              0.5570       65.1665     12.3922       5.2587   <2e-16 ***
## Ylag1          0.3820       45.1076     16.2420       2.7772   0.0115 *  
## Ylag2          0.0339        4.0555     16.6120       0.2441   0.8096    
## Ylag3         -0.0172       -2.0526     16.6366      -0.1234   0.9030    
## Ylag4         -0.2086      -24.7381     16.8332      -1.4696   0.1569    
## Ylag5          0.0100        1.1793     16.7276       0.0705   0.9445    
## Ylag6         -0.1942      -22.2645     20.8436      -1.0682   0.2979    
## Ylag7          0.1815       20.9429     23.4213       0.8942   0.3816    
## Ylag8          0.1750       20.3283     16.2906       1.2479   0.2262    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Ridge Summary
##        R2    adj-R2  DF ridge         F       AIC       BIC 
##   0.99220   0.98920   8.51392 332.61624  46.93097 160.89657 
## Ridge minimum MSE= 2032.758 at K= 0.002 
## P-value for F-test ( 8.51392 , 21.05379 ) = 1.628288e-20 
## -------------------------------------------------------------------
## 
## 
## Coefficients: for Ridge parameter K= 0.001 
##              Estimate Estimate (Sc) StdErr (Sc) t-value (Sc) Pr(>|t|)    
## Intercept      5.0340   -31004.6153  13968.7336      -2.2196   0.0377 *  
## Y              0.5542       64.8350     11.9558       5.4229   <2e-16 ***
## Ylag1          0.3801       44.8772     15.4422       2.9061   0.0085 ** 
## Ylag2          0.0378        4.5149     15.8634       0.2846   0.7788    
## Ylag3         -0.0207       -2.4675     15.8875      -0.1553   0.8781    
## Ylag4         -0.2014      -23.8860     16.0011      -1.4928   0.1505    
## Ylag5          0.0016        0.1858     15.8760       0.0117   0.9908    
## Ylag6         -0.1798      -20.6085     19.1801      -1.0745   0.2949    
## Ylag7          0.1677       19.3503     21.0354       0.9199   0.3682    
## Ylag8          0.1800       20.9105     15.1547       1.3798   0.1823    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Ridge Summary
##        R2    adj-R2  DF ridge         F       AIC       BIC 
##   0.99160   0.98840   8.24438 333.04473  46.45383 160.04175 
## Ridge minimum MSE= 2032.758 at K= 0.002 
## P-value for F-test ( 8.24438 , 21.12448 ) = 1.649472e-20 
## -------------------------------------------------------------------
## 
## 
## Coefficients: for Ridge parameter K= 0.0014 
##              Estimate Estimate (Sc) StdErr (Sc) t-value (Sc) Pr(>|t|)    
## Intercept      5.0664   -30998.0305  13174.6182      -2.3529   0.0285 *  
## Y              0.5515       64.5246     11.5665       5.5786   <2e-16 ***
## Ylag1          0.3781       44.6365     14.7386       3.0285   0.0064 ** 
## Ylag2          0.0414        4.9484     15.1944       0.3257   0.7479    
## Ylag3         -0.0233       -2.7886     15.2194      -0.1832   0.8564    
## Ylag4         -0.1953      -23.1623     15.2739      -1.5165   0.1443    
## Ylag5         -0.0055       -0.6477     15.1407      -0.0428   0.9663    
## Ylag6         -0.1679      -19.2435     17.8261      -1.0795   0.2926    
## Ylag7          0.1567       18.0894     19.1235       0.9459   0.3549    
## Ylag8          0.1837       21.3418     14.2277       1.5000   0.1485    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Ridge Summary
##        R2    adj-R2  DF ridge         F       AIC       BIC 
##   0.99110   0.98770   8.00638 333.50892  46.05379 159.30823 
## Ridge minimum MSE= 2032.758 at K= 0.002 
## P-value for F-test ( 8.00638 , 21.20755 ) = 1.615039e-20 
## -------------------------------------------------------------------
## 
## 
## Coefficients: for Ridge parameter K= 0.002 
##              Estimate Estimate (Sc) StdErr (Sc) t-value (Sc) Pr(>|t|)    
## Intercept      5.1210   -30988.6845  12196.5462      -2.5408   0.0189 *  
## Y              0.5478       64.0843     11.0524       5.7982   <2e-16 ***
## Ylag1          0.3750       44.2741     13.8249       3.2025   0.0042 ** 
## Ylag2          0.0464        5.5497     14.3125       0.3877   0.7020    
## Ylag3         -0.0263       -3.1413     14.3394      -0.2191   0.8287    
## Ylag4         -0.1876      -22.2516     14.3334      -1.5524   0.1353    
## Ylag5         -0.0142       -1.6750     14.2006      -0.1180   0.9072    
## Ylag6         -0.1534      -17.5850     16.1999      -1.0855   0.2898    
## Ylag7          0.1441       16.6269     16.8765       0.9852   0.3356    
## Ylag8          0.1876       21.7973     13.1103       1.6626   0.1110    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Ridge Summary
##        R2    adj-R2  DF ridge         F       AIC       BIC 
##   0.99030   0.98660   7.69473 334.16792  45.56150 158.37926 
## Ridge minimum MSE= 2032.758 at K= 0.002 
## P-value for F-test ( 7.69473 , 21.34246 ) = 1.515096e-20 
## -------------------------------------------------------------------
print(ridge)
## Call:
## lmridge.default(formula = C ~ ., data = dados, K = lambdas, scaling = "sc")
## 
##          Intercept       Y   Ylag1   Ylag2    Ylag3    Ylag4    Ylag5    Ylag6
## K=0        4.97793 0.56185 0.38448 0.02783 -0.00986 -0.22229  0.02627 -0.22304
## K=2e-04    4.98526 0.56014 0.38378 0.02989 -0.01265 -0.21722  0.02025 -0.21224
## K=6e-04    5.00642 0.55703 0.38205 0.03392 -0.01718 -0.20855  0.01000 -0.19425
## K=0.001    5.03404 0.55419 0.38010 0.03776 -0.02066 -0.20137  0.00158 -0.17980
## K=0.0014   5.06635 0.55154 0.37806 0.04139 -0.02335 -0.19527 -0.00549 -0.16789
## K=0.002    5.12103 0.54778 0.37500 0.04642 -0.02630 -0.18759 -0.01421 -0.15342
##            Ylag7   Ylag8
## K=0      0.21052 0.16361
## K=2e-04  0.19940 0.16808
## K=6e-04  0.18146 0.17499
## K=0.001  0.16766 0.18000
## K=0.0014 0.15673 0.18371
## K=0.002  0.14406 0.18763

Na função acima, ao definirmos scaling=“sc” informamos ao R para o método para padronizar os preditores. A opção scaling=“sc” escala (trata) os preditores para a forma de correlação, de modo que a matriz de correlação tenha elementos de sua diagonal iguais a 1. A opção scaling=“scaled” padroniza os preditores para ter média zero e variância um. a opção scaling=“centered” centraliza os preditores.

Os resultados gerados pela função summary(ridge) nos apontam a questão da significância somente até o segundo o lag(Y) para todos os valores de \(\lambda\) (K) definidos por Maddala, 2001.

Como todas as estimativas apontaram para os valores de MSE (em português erro quadrático médio, EQM) iguais, veremos como se comportam os valores de \(\lambda\) nos coeficientes:

ridge$coef
##              K=0    K=2e-04    K=6e-04     K=0.001    K=0.0014    K=0.002
## Y      65.731305  65.530790  65.166526  64.8350317  64.5245663  64.084283
## Ylag1  45.394476  45.311412  45.107600  44.8771691  44.6364639  44.274149
## Ylag2   3.327698   3.573930   4.055495   4.5148784   4.9484288   5.549673
## Ylag3  -1.177202  -1.510742  -2.052591  -2.4675231  -2.7885911  -3.141285
## Ylag4 -26.367967 -25.766077 -24.738143 -23.8860275 -23.1623227 -22.251586
## Ylag5   3.097333   2.387521   1.179310   0.1858217  -0.6476783  -1.675005
## Ylag6 -25.564391 -24.326547 -22.264459 -20.6085035 -19.2434951 -17.585024
## Ylag7  24.297507  23.013143  20.942943  19.3502803  18.0894170  16.626918
## Ylag8  19.006640  19.525088  20.328278  20.9105339  21.3418083  21.797274
colSums(ridge$coef)
##      K=0  K=2e-04  K=6e-04  K=0.001 K=0.0014  K=0.002 
## 107.7454 107.7385 107.7250 107.7117 107.6986 107.6794

Esse resultado das somas dos coeficientes vai contra o que Maddala, 2001, p. 150, obteve:

“Note que conforme \(\lambda\) aumenta, há uma suavização dos coeficientes e a estimativa de \(\beta_{0}\) diminui.”

Vamos ver como o EQM se comporta para cada valor de \(\lambda\)

#Utilize o comando ridge$rfit para ver o modelo ajustado ou então o comando predict(ridge) para os valores projetados.

eqm_i<-press(ridge)

eqm_i
##             K=0    K=2e-04     K=6e-04     K=0.001   K=0.0014    K=0.002
## 1  -3.436412270 -3.4622053 -3.50967900 -3.55321370 -3.5940000 -3.6515494
## 2   0.882456270  0.8729025  0.84913827  0.82107791  0.7901982  0.7405415
## 3   1.643144090  1.6189014  1.57465346  1.53437308  1.4968753  1.4441941
## 4   1.870306577  1.8579476  1.83493609  1.81371286  1.7938880  1.7662322
## 5   3.161070410  3.1730853  3.19314265  3.20925511  3.2225223  3.2387226
## 6   1.951052415  1.9537015  1.96047465  1.96901220  1.9790485  1.9963839
## 7   2.465231392  2.4987973  2.56123437  2.61882573  2.6726713  2.7480497
## 8   0.003445359  0.0161265  0.04429632  0.07511198  0.1076929  0.1586658
## 9   0.425316754  0.4490045  0.49302134  0.53335131  0.5707011  0.6223161
## 10  0.401173510  0.3814554  0.34738473  0.31915829  0.2955884  0.2671314
## 11 -3.350856906 -3.2577319 -3.10526691 -2.98515293 -2.8876692 -2.7711449
## 12  0.616961476  0.5466639  0.43483191  0.34962277  0.2823566  0.2041038
## 13  0.107127368  0.1461352  0.20585262  0.24849054  0.2795557  0.3115193
## 14 -1.116029953 -1.1369548 -1.17380200 -1.20536850 -1.2329051 -1.2684007
## 15 -1.863538427 -1.8077179 -1.71740348 -1.64739119 -1.5914957 -1.5259834
## 16 -1.704845464 -1.7381579 -1.79282315 -1.83650252 -1.8728205 -1.9180726
## 17 -3.918873258 -3.8900254 -3.84822397 -3.82155109 -3.8053259 -3.7943232
## 18 -0.493640945 -0.5421762 -0.62711145 -0.70027376 -0.7650708 -0.8510526
## 19 -2.948021867 -2.9117795 -2.85140373 -2.80291913 -2.7629462 -2.7143896
## 20 -4.022087627 -3.9640745 -3.86093264 -3.77091884 -3.6909533 -3.5855423
## 21 -1.925655468 -1.9122636 -1.88553276 -1.85885380 -1.8322340 -1.7925779
## 22 -2.612257266 -2.5171418 -2.35802336 -2.22793761 -2.1176027 -1.9773375
## 23 -1.703008612 -1.6886501 -1.65498015 -1.61768007 -1.5787394 -1.5196118
## 24  2.277639927  2.2742372  2.26843581  2.26363952  2.2597391  2.2551747
## 25 -1.751299809 -1.7483210 -1.73096984 -1.70393200 -1.6712660 -1.6167103
## 26  3.888432693  3.8564253  3.79758627  3.74481395  3.6975268  3.6354183
## 27  1.544042873  1.4993854  1.41835607  1.34726254  1.2847379  1.2043188
## 28  8.152254138  7.8519738  7.34698245  6.93597022  6.5927383  6.1694591
## 29  5.538292585  5.3088905  4.91586915  4.58981897  4.3133773  3.9672448
## 30  4.896907396  4.8467930  4.75220934  4.66526302  4.5852677  4.4768230

A função press é uma função genérica que calcula a soma dos quadrados do erro residual de previsão (prediction residual error sum of squares = PRESS) para coeficientes ridge.

colSums(eqm_i)
##      K=0  K=2e-04  K=6e-04  K=0.001 K=0.0014  K=0.002 
## 8.978327 8.575227 7.882253 7.307065 6.821457 6.219603

Assim, notamos que ao valor de \(K=\lambda=0.002\) temos o menor EQM.

A função kest(), que funciona com o modelo ridge ajustado, calcula diferentes parâmetros viés desenvolvido por diferentes pesquisadores. A lista de diferentes valores de k (22 no total no pacote lmridge) pode ajudar em decidir a quantidade de viés precisa ser introduzido no RR.

kest<-kest(ridge)

kest
## Ridge k from different Authors
## 
##                               k values
## Thisted (1976):                0.00311
## Dwividi & Srivastava (1978):   0.00044
## LW (lm.ridge)                  0.07022
## LW (1976)                      0.00301
## HKB (1975)                     0.00400
## Kibria (2003) (AM)             0.39692
## Minimum GCV at                 0.00200
## Minimum CV at                  0.00200
## Kibria 2003 (GM):              0.01451
## Kibria 2003 (MED):             0.01070
## Muniz et al. 2009 (KM2):      33.42384
## Muniz et al. 2009 (KM3):       0.43561
## Muniz et al. 2009 (KM4):       8.30103
## Muniz et al. 2009 (KM5):       0.12047
## Muniz et al. 2009 (KM6):       9.66661
## Mansson et al. 2012 (KMN8):   33.45992
## Mansson et al. 2012 (KMN9):    0.36078
## Mansson et al. 2012 (KMN10):   8.82099
## Mansson et al. 2012 (KMN11):   0.11337
## Mansson et al. 2012 (KMN12):   9.79061
## Dorugade et al. 2010:          0.00000
## Dorugade et al. 2014:          0.00000

Isso nos levaria a fazer um exercício com todos esses valores sugeridos por esses diferentes pesquisadores com os valores de \(\lambda=\)k values. (vamos deixar isso para depois).

As funções rstats1() e rstats2() podem ser usadas para calcular estatísticas diferentes para um determinado parâmetro ridge estimado especificado em uma função lmridge. As estatísticas do modelo ridge são MSE, desvio-quadrático, Estatísticas \(F\), variância ridge, graus de liberdade por Hastie e Tibshirani (1990), números de condição, PRESS, \(R^{2}\), e ISRM etc. A seguir estão os resultados usando as funções rstats1() e rstats2(), para os valores de \(\lambda\) em Maddala, 2001, p. 150:

rstats1(ridge)
## 
## Ridge Regression Statistics 1:
## 
##          Variance   Bias^2      MSE rsigma2        F     R2 adj-R2       CN
## K=0      3538.966   0.0000 3538.966  3.8649 332.2669 0.9930 0.9904 3307.218
## K=2e-04  3244.689   4.5357 3249.224  3.8643 332.3170 0.9927 0.9900 3073.710
## K=6e-04  2781.667  31.9218 2813.589  3.8609 332.6162 0.9922 0.9892 2693.398
## K=0.001  2433.572  71.4428 2505.015  3.8559 333.0447 0.9916 0.9884 2396.861
## K=0.0014 2161.943 115.5025 2277.445  3.8505 333.5089 0.9911 0.9877 2159.164
## K=0.002  1849.980 182.7783 2032.758  3.8429 334.1679 0.9903 0.9866 1879.596

Note que o menor valor de MSE (EQM) é para \(\lambda=0.002\) com a menor variância e menor CN (Número de Condição, identifica a multicolinearidade). Veremos as próximas estatísticas:

rstats2(ridge)
## 
## Ridge Regression Statistics 2:
## 
##                CK DF ridge     EP    REDF      EF   ISRM m scale    PRESS
## K= 0      11.0000   9.0000 9.0001 20.9999  0.0000 8.9804  0.0000 259.0208
## K= 2e-04  10.6567   8.8247 8.9926 21.0074 64.7717 8.9794  0.1753 248.9542
## K= 6e-04  10.0816   8.5139 8.9462 21.0538 23.6319 8.9776  0.4861 232.6630
## K= 0.001   9.6132   8.2444 8.8755 21.1245 15.3926 8.9759  0.7556 220.0163
## K= 0.0014  9.2203   8.0064 8.7924 21.2076 11.8520 8.9743  0.9936 209.8984
## K= 0.002   8.7319   7.6947 8.6575 21.3425  9.1827 8.9721  1.3053 198.0194

Os resíduos, valores ajustados da regressão ridge (RR) e valores previstos da variável de resposta (C = consumo real per capita) podem ser calculados usando as funções residual(), fitted() e predict(), respectivamente. Para obter matriz de Var-Cov, FIV e matriz estimada (“matriz-chapéu”), as funções vcov(), vif() e hatr() podem ser usadas. Os graus de liberdade são calculados seguindo Hastie e Tibshirani (1990). Os resultados para FIV, Var-Cov e elementos diagonais da matriz estimada das funções vif(), vcov() e hatr() são fornecidas abaixo para o objeto lambdas.

hatr(ridge)
## [[1]]
##           1        2        3        4        5        6        7        8
## 1   0.21630  0.15038  0.12691  0.03878  0.01564 -0.02500 -0.01649 -0.01357
## 2   0.15038  0.19628  0.13046  0.08254  0.05862 -0.00535 -0.03568 -0.03405
## 3   0.12691  0.13046  0.16749  0.12075  0.07121  0.03118 -0.01575 -0.04724
## 4   0.03878  0.08254  0.12075  0.16516  0.11570  0.08044  0.02452 -0.02388
## 5   0.01564  0.05862  0.07121  0.11570  0.16202  0.09218  0.07903  0.02343
## 6  -0.02500 -0.00535  0.03118  0.08044  0.09218  0.19742  0.10897  0.10208
## 7  -0.01649 -0.03568 -0.01575  0.02452  0.07903  0.10897  0.20424  0.11676
## 8  -0.01357 -0.03405 -0.04724 -0.02388  0.02343  0.10208  0.11676  0.21295
## 9   0.06751 -0.01515 -0.03108 -0.08026  0.00188 -0.00399  0.08816  0.09537
## 10  0.05345  0.02026 -0.04383 -0.04412 -0.08867  0.03624  0.00438  0.09779
## 11  0.04324  0.07021 -0.01709 -0.06498 -0.05085 -0.08110  0.05420  0.02599
## 12  0.05982 -0.00471  0.04073  0.00722 -0.10205 -0.04935 -0.08636  0.05310
## 13 -0.01780  0.04427 -0.00307  0.03028  0.01578 -0.09151 -0.05003 -0.08905
## 14 -0.01320 -0.00012 -0.00628  0.03934 -0.03166  0.01447 -0.07234 -0.01688
## 15 -0.03681  0.02516 -0.02170 -0.00527  0.02617 -0.03520  0.03022 -0.05116
## 16  0.07973 -0.01433  0.02781 -0.01490 -0.00955 -0.05864 -0.06617 -0.00519
## 17  0.04267  0.07914  0.01569 -0.02063  0.03874 -0.04293 -0.08246 -0.10367
## 18  0.08207  0.03235  0.06989  0.01496 -0.02664 -0.00241 -0.06155 -0.10393
## 19 -0.09142  0.02064  0.03425  0.07218  0.01425  0.04640  0.01072 -0.04693
## 20 -0.06462 -0.11059  0.04769  0.06971  0.06162 -0.01520  0.02120 -0.01659
## 21 -0.14910 -0.10648 -0.06487  0.05983  0.08827  0.09152 -0.02671  0.00480
## 22 -0.14710 -0.11088 -0.12425 -0.04318  0.03429  0.12086  0.12241  0.01495
## 23 -0.00244 -0.10442 -0.10378 -0.12599 -0.03749 -0.02105  0.10746  0.10648
## 24 -0.01473 -0.03396 -0.06975 -0.14479 -0.07500 -0.02882 -0.03682  0.07960
## 25 -0.10206 -0.14518 -0.04184 -0.03325 -0.17765  0.03898 -0.01511 -0.01701
## 26 -0.08985 -0.09365 -0.11127 -0.02813 -0.02288 -0.20475  0.02078 -0.03734
## 27 -0.09445 -0.03610 -0.09739 -0.09597 -0.04083 -0.04036 -0.19502  0.03565
## 28  0.04634 -0.08866 -0.02697 -0.08992 -0.09679 -0.10347 -0.06835 -0.22765
## 29 -0.04244  0.04555 -0.08892 -0.03363 -0.08499 -0.08561 -0.09887 -0.06386
## 30 -0.10176 -0.01655  0.03101 -0.07249 -0.05381 -0.06600 -0.06532 -0.07095
##           9       10       11       12       13       14       15       16
## 1   0.06751  0.05345  0.04324  0.05982 -0.01780 -0.01320 -0.03681  0.07973
## 2  -0.01515  0.02026  0.07021 -0.00471  0.04427 -0.00012  0.02516 -0.01433
## 3  -0.03108 -0.04383 -0.01709  0.04073 -0.00307 -0.00628 -0.02170  0.02781
## 4  -0.08026 -0.04412 -0.06498  0.00722  0.03028  0.03934 -0.00527 -0.01490
## 5   0.00188 -0.08867 -0.05085 -0.10205  0.01578 -0.03166  0.02617 -0.00955
## 6  -0.00399  0.03624 -0.08110 -0.04935 -0.09151  0.01447 -0.03520 -0.05864
## 7   0.08816  0.00438  0.05420 -0.08636 -0.05003 -0.07234  0.03022 -0.06617
## 8   0.09537  0.09779  0.02599  0.05310 -0.08905 -0.01688 -0.05116 -0.00519
## 9   0.22414  0.05072  0.10976 -0.00310  0.03736 -0.07000  0.01318  0.00379
## 10  0.05072  0.23121  0.06665  0.11148 -0.00912  0.08909 -0.04472 -0.04333
## 11  0.10976  0.06665  0.27405 -0.00396  0.12572 -0.06117  0.10892 -0.13151
## 12 -0.00310  0.11148 -0.00396  0.30072  0.00331  0.09233 -0.11494  0.08295
## 13  0.03736 -0.00912  0.12572  0.00331  0.29136  0.04804  0.11459 -0.10966
## 14 -0.07000  0.08909 -0.06117  0.09233  0.04804  0.12241 -0.03833 -0.00737
## 15  0.01318 -0.04472  0.10892 -0.11494  0.11459 -0.03833  0.11149 -0.10599
## 16  0.00379 -0.04333 -0.13151  0.08295 -0.10966 -0.00737 -0.10599  0.20959
## 17  0.00606 -0.06439 -0.01275 -0.14613  0.04919 -0.02806  0.05443  0.01209
## 18 -0.09003 -0.03092 -0.11867 -0.02353 -0.14724 -0.00187 -0.06220  0.10116
## 19 -0.17993 -0.05974  0.00249 -0.05154 -0.04033  0.00001  0.04241 -0.10692
## 20 -0.04878 -0.20320 -0.14932  0.07158 -0.05727 -0.04758 -0.06191  0.13645
## 21 -0.06424 -0.05464 -0.20958 -0.04992  0.04352  0.09033 -0.02547  0.01399
## 22  0.01744  0.00228 -0.02101 -0.23426 -0.01995 -0.02192  0.07694 -0.14145
## 23  0.06891 -0.01061 -0.02454 -0.05949 -0.22660 -0.11144 -0.05163  0.13002
## 24  0.07659  0.02282  0.03504  0.00507 -0.10071 -0.06616 -0.03095  0.04161
## 25 -0.06056  0.12961  0.00423  0.18335 -0.01465  0.10351 -0.05414 -0.10373
## 26 -0.00250 -0.08310  0.09285  0.04095  0.17508 -0.00801  0.08129  0.03424
## 27  0.00764  0.02109 -0.08339  0.05582  0.06515  0.07178 -0.03973  0.04823
## 28  0.06814 -0.04082 -0.05315 -0.08409  0.05398 -0.00316  0.02068  0.05425
## 29 -0.23351  0.07323 -0.02016 -0.05626 -0.08637  0.07530  0.01449  0.00807
## 30 -0.05352 -0.18909  0.08986 -0.03876 -0.03428 -0.14105  0.06020 -0.06522
##          17       18       19       20       21       22       23       24
## 1   0.04267  0.08207 -0.09142 -0.06462 -0.14910 -0.14710 -0.00244 -0.01473
## 2   0.07914  0.03235  0.02064 -0.11059 -0.10648 -0.11088 -0.10442 -0.03396
## 3   0.01569  0.06989  0.03425  0.04769 -0.06487 -0.12425 -0.10378 -0.06975
## 4  -0.02063  0.01496  0.07218  0.06971  0.05983 -0.04318 -0.12599 -0.14479
## 5   0.03874 -0.02664  0.01425  0.06162  0.08827  0.03429 -0.03749 -0.07500
## 6  -0.04293 -0.00241  0.04640 -0.01520  0.09152  0.12086 -0.02105 -0.02882
## 7  -0.08246 -0.06155  0.01072  0.02120 -0.02671  0.12241  0.10746 -0.03682
## 8  -0.10367 -0.10393 -0.04693 -0.01659  0.00480  0.01495  0.10648  0.07960
## 9   0.00606 -0.09003 -0.17993 -0.04878 -0.06424  0.01744  0.06891  0.07659
## 10 -0.06439 -0.03092 -0.05974 -0.20320 -0.05464  0.00228 -0.01061  0.02282
## 11 -0.01275 -0.11867  0.00249 -0.14932 -0.20958 -0.02101 -0.02454  0.03504
## 12 -0.14613 -0.02353 -0.05154  0.07158 -0.04992 -0.23426 -0.05949  0.00507
## 13  0.04919 -0.14724 -0.04033 -0.05727  0.04352 -0.01995 -0.22660 -0.10071
## 14 -0.02806 -0.00187  0.00001 -0.04758  0.09033 -0.02192 -0.11144 -0.06616
## 15  0.05443 -0.06220  0.04241 -0.06191 -0.02547  0.07694 -0.05163 -0.03095
## 16  0.01209  0.10116 -0.10692  0.13645  0.01399 -0.14145  0.13002  0.04161
## 17  0.19860  0.05475 -0.04330 -0.10041  0.02740  0.04172 -0.04316  0.04017
## 18  0.05475  0.21671  0.03529  0.01666 -0.05245 -0.02011  0.06693 -0.00829
## 19 -0.04330  0.03529  0.24759  0.02371 -0.02583  0.04376 -0.05759 -0.05394
## 20 -0.10041  0.01666  0.02371  0.37973  0.09165 -0.10575  0.06447 -0.05283
## 21  0.02740 -0.05245 -0.02583  0.09165  0.33226  0.12062 -0.08347 -0.06232
## 22  0.04172 -0.02011  0.04376 -0.10575  0.12062  0.33440  0.04882 -0.00935
## 23 -0.04316  0.06693 -0.05759  0.06447 -0.08347  0.04882  0.37210  0.12211
## 24  0.04017 -0.00829 -0.05394 -0.05283 -0.06232 -0.00935  0.12211  0.21964
## 25 -0.19495  0.01676  0.09624  0.00758 -0.02842  0.04799 -0.09888 -0.04101
## 26 -0.08740 -0.14297 -0.02834  0.16619  0.01270 -0.08003  0.08585 -0.10724
## 27  0.11873 -0.09686 -0.10734 -0.05920  0.20216 -0.03912 -0.09961  0.18281
## 28  0.11945  0.16515 -0.14039 -0.01468 -0.00433  0.11534  0.00773 -0.05082
## 29  0.03818  0.11150  0.16258 -0.16306 -0.03719  0.01853  0.11312 -0.01014
## 30  0.03321  0.00550  0.18102  0.11278 -0.13404 -0.04200 -0.03183  0.17219
##          25       26       27       28       29       30
## 1  -0.10206 -0.08985 -0.09445  0.04634 -0.04244 -0.10176
## 2  -0.14518 -0.09365 -0.03610 -0.08866  0.04555 -0.01655
## 3  -0.04184 -0.11127 -0.09739 -0.02697 -0.08892  0.03101
## 4  -0.03325 -0.02813 -0.09597 -0.08992 -0.03363 -0.07249
## 5  -0.17765 -0.02288 -0.04083 -0.09679 -0.08499 -0.05381
## 6   0.03898 -0.20475 -0.04036 -0.10347 -0.08561 -0.06600
## 7  -0.01511  0.02078 -0.19502 -0.06835 -0.09887 -0.06532
## 8  -0.01701 -0.03734  0.03565 -0.22765 -0.06386 -0.07095
## 9  -0.06056 -0.00250  0.00764  0.06814 -0.23351 -0.05352
## 10  0.12961 -0.08310  0.02109 -0.04082  0.07323 -0.18909
## 11  0.00423  0.09285 -0.08339 -0.05315 -0.02016  0.08986
## 12  0.18335  0.04095  0.05582 -0.08409 -0.05626 -0.03876
## 13 -0.01465  0.17508  0.06515  0.05398 -0.08637 -0.03428
## 14  0.10351 -0.00801  0.07178 -0.00316  0.07530 -0.14105
## 15 -0.05414  0.08129 -0.03973  0.02068  0.01449  0.06020
## 16 -0.10373  0.03424  0.04823  0.05425  0.00807 -0.06522
## 17 -0.19495 -0.08740  0.11873  0.11945  0.03818  0.03321
## 18  0.01676 -0.14297 -0.09686  0.16515  0.11150  0.00550
## 19  0.09624 -0.02834 -0.10734 -0.14039  0.16258  0.18102
## 20  0.00758  0.16619 -0.05920 -0.01468 -0.16306  0.11278
## 21 -0.02842  0.01270  0.20216 -0.00433 -0.03719 -0.13404
## 22  0.04799 -0.08003 -0.03912  0.11534  0.01853 -0.04200
## 23 -0.09888  0.08585 -0.09961  0.00773  0.11312 -0.03183
## 24 -0.04101 -0.10724  0.18281 -0.05082 -0.01014  0.17219
## 25  0.52542 -0.07336 -0.09356  0.13234 -0.06173  0.07108
## 26 -0.07336  0.56458 -0.07809 -0.01916  0.11612 -0.09254
## 27 -0.09356 -0.07809  0.51603 -0.09696 -0.00724  0.07615
## 28  0.13234 -0.01916 -0.09696  0.60305 -0.11196 -0.06512
## 29 -0.06173  0.11612 -0.00724 -0.11196  0.60551 -0.09626
## 30  0.07108 -0.09254  0.07615 -0.06512 -0.09626  0.59757
## 
## [[2]]
##           1        2        3        4        5        6        7        8
## 1   0.21408  0.15125  0.12588  0.03933  0.01662 -0.02422 -0.01621 -0.01360
## 2   0.15125  0.19488  0.13113  0.08277  0.05803 -0.00539 -0.03584 -0.03384
## 3   0.12588  0.13113  0.16652  0.12075  0.07182  0.03155 -0.01546 -0.04717
## 4   0.03933  0.08277  0.12075  0.16426  0.11565  0.08014  0.02498 -0.02373
## 5   0.01662  0.05803  0.07182  0.11565  0.16078  0.09252  0.07858  0.02391
## 6  -0.02422 -0.00539  0.03155  0.08014  0.09252  0.19584  0.10944  0.10155
## 7  -0.01621 -0.03584 -0.01546  0.02498  0.07858  0.10944  0.20242  0.11718
## 8  -0.01360 -0.03384 -0.04717 -0.02373  0.02391  0.10155  0.11718  0.21129
## 9   0.06653 -0.01492 -0.03143 -0.07910  0.00133 -0.00273  0.08723  0.09608
## 10  0.05382  0.02011 -0.04330 -0.04459 -0.08761  0.03452  0.00552  0.09691
## 11  0.04524  0.06786 -0.01587 -0.06403 -0.05250 -0.08021  0.05170  0.02718
## 12  0.05734 -0.00201  0.03863  0.00624 -0.09946 -0.04953 -0.08385  0.05122
## 13 -0.01476  0.04240 -0.00152  0.02971  0.01317 -0.09091 -0.05082 -0.08682
## 14 -0.01257  0.00025 -0.00599  0.03802 -0.03102  0.01302 -0.07051 -0.01733
## 15 -0.03431  0.02293 -0.02012 -0.00491  0.02400 -0.03471  0.02824 -0.04951
## 16  0.07576 -0.01150  0.02566 -0.01481 -0.00762 -0.05754 -0.06448 -0.00656
## 17  0.04376  0.07737  0.01684 -0.01988  0.03709 -0.04278 -0.08286 -0.10250
## 18  0.07937  0.03385  0.06852  0.01518 -0.02470 -0.00261 -0.06090 -0.10428
## 19 -0.08924  0.01919  0.03511  0.07172  0.01401  0.04536  0.00983 -0.04714
## 20 -0.06782 -0.10723  0.04500  0.06932  0.06288 -0.01319  0.02169 -0.01724
## 21 -0.14763 -0.10618 -0.06406  0.05844  0.08748  0.09026 -0.02478  0.00472
## 22 -0.14439 -0.11282 -0.12219 -0.04293  0.03266  0.11958  0.12076  0.01643
## 23 -0.00559 -0.10293 -0.10488 -0.12480 -0.03613 -0.01978  0.10655  0.10514
## 24 -0.01543 -0.03435 -0.06999 -0.14352 -0.07472 -0.02885 -0.03663  0.07835
## 25 -0.10280 -0.14326 -0.04322 -0.03436 -0.17511  0.03720 -0.01419 -0.01724
## 26 -0.08953 -0.09335 -0.11103 -0.02887 -0.02430 -0.20207  0.01931 -0.03647
## 27 -0.09273 -0.03720 -0.09638 -0.09625 -0.04183 -0.04172 -0.19219  0.03430
## 28  0.04342 -0.08678 -0.02840 -0.08933 -0.09620 -0.10232 -0.06901 -0.22473
## 29 -0.04048  0.04348 -0.08683 -0.03448 -0.08482 -0.08730 -0.09858 -0.06520
## 30 -0.10109 -0.01790  0.03043 -0.07094 -0.05452 -0.06510 -0.06712 -0.07091
##           9       10       11       12       13       14       15       16
## 1   0.06653  0.05382  0.04524  0.05734 -0.01476 -0.01257 -0.03431  0.07576
## 2  -0.01492  0.02011  0.06786 -0.00201  0.04240  0.00025  0.02293 -0.01150
## 3  -0.03143 -0.04330 -0.01587  0.03863 -0.00152 -0.00599 -0.02012  0.02566
## 4  -0.07910 -0.04459 -0.06403  0.00624  0.02971  0.03802 -0.00491 -0.01481
## 5   0.00133 -0.08761 -0.05250 -0.09946  0.01317 -0.03102  0.02400 -0.00762
## 6  -0.00273  0.03452 -0.08021 -0.04953 -0.09091  0.01302 -0.03471 -0.05754
## 7   0.08723  0.00552  0.05170 -0.08385 -0.05082 -0.07051  0.02824 -0.06448
## 8   0.09608  0.09691  0.02718  0.05122 -0.08682 -0.01733 -0.04951 -0.00656
## 9   0.22114  0.05307  0.10836 -0.00142  0.03671 -0.06736  0.01219  0.00308
## 10  0.05307  0.22792  0.06854  0.10995 -0.00749  0.08634 -0.04315 -0.04302
## 11  0.10836  0.06854  0.26642  0.00340  0.12050 -0.05793  0.10233 -0.12435
## 12 -0.00142  0.10995  0.00340  0.29048  0.00993  0.08959 -0.10717  0.07451
## 13  0.03671 -0.00749  0.12050  0.00993  0.28283  0.04853  0.10814 -0.10251
## 14 -0.06736  0.08634 -0.05793  0.08959  0.04853  0.11872 -0.03627 -0.00793
## 15  0.01219 -0.04315  0.10233 -0.10717  0.10814 -0.03627  0.10477 -0.09854
## 16  0.00308 -0.04302 -0.12435  0.07451 -0.10251 -0.00793 -0.09854  0.19916
## 17  0.00464 -0.06354 -0.01615 -0.14043  0.04504 -0.02685  0.05037  0.01620
## 18 -0.08987 -0.03197 -0.11458 -0.02791 -0.14183 -0.00247 -0.05774  0.09593
## 19 -0.17785 -0.06087 -0.00076 -0.04896 -0.04206 -0.00030  0.03966 -0.10185
## 20 -0.05026 -0.20049 -0.14392  0.06342 -0.05212 -0.04668 -0.05590  0.12703
## 21 -0.06267 -0.05609 -0.20664 -0.05080  0.04143  0.08696 -0.02477  0.01419
## 22  0.01738  0.00169 -0.02593 -0.22635 -0.02521 -0.02152  0.07111 -0.13351
## 23  0.06754 -0.00979 -0.02222 -0.06288 -0.22038 -0.10941 -0.04785  0.12368
## 24  0.07546  0.02312  0.03465  0.00496 -0.09873 -0.06468 -0.03030  0.04065
## 25 -0.05835  0.12700  0.00820  0.17756 -0.01072  0.10074 -0.04991 -0.10596
## 26 -0.00317 -0.08025  0.09106  0.04169  0.17206 -0.00666  0.07938  0.03376
## 27  0.00856  0.01963 -0.08198  0.05580  0.06305  0.06937 -0.03964  0.04937
## 28  0.06481 -0.03901 -0.05129 -0.08427  0.05461 -0.00182  0.02184  0.05088
## 29 -0.22893  0.06891 -0.02107 -0.05448 -0.08632  0.07222  0.01329  0.01186
## 30 -0.05603 -0.18586  0.08400 -0.03519 -0.03594 -0.13643  0.05658 -0.06157
##          17       18       19       20       21       22       23       24
## 1   0.04376  0.07937 -0.08924 -0.06782 -0.14763 -0.14439 -0.00559 -0.01543
## 2   0.07737  0.03385  0.01919 -0.10723 -0.10618 -0.11282 -0.10293 -0.03435
## 3   0.01684  0.06852  0.03511  0.04500 -0.06406 -0.12219 -0.10488 -0.06999
## 4  -0.01988  0.01518  0.07172  0.06932  0.05844 -0.04293 -0.12480 -0.14352
## 5   0.03709 -0.02470  0.01401  0.06288  0.08748  0.03266 -0.03613 -0.07472
## 6  -0.04278 -0.00261  0.04536 -0.01319  0.09026  0.11958 -0.01978 -0.02885
## 7  -0.08286 -0.06090  0.00983  0.02169 -0.02478  0.12076  0.10655 -0.03663
## 8  -0.10250 -0.10428 -0.04714 -0.01724  0.00472  0.01643  0.10514  0.07835
## 9   0.00464 -0.08987 -0.17785 -0.05026 -0.06267  0.01738  0.06754  0.07546
## 10 -0.06354 -0.03197 -0.06087 -0.20049 -0.05609  0.00169 -0.00979  0.02312
## 11 -0.01615 -0.11458 -0.00076 -0.14392 -0.20664 -0.02593 -0.02222  0.03465
## 12 -0.14043 -0.02791 -0.04896  0.06342 -0.05080 -0.22635 -0.06288  0.00496
## 13  0.04504 -0.14183 -0.04206 -0.05212  0.04143 -0.02521 -0.22038 -0.09873
## 14 -0.02685 -0.00247 -0.00030 -0.04668  0.08696 -0.02152 -0.10941 -0.06468
## 15  0.05037 -0.05774  0.03966 -0.05590 -0.02477  0.07111 -0.04785 -0.03030
## 16  0.01620  0.09593 -0.10185  0.12703  0.01419 -0.13351  0.12368  0.04065
## 17  0.19423  0.05728 -0.04350 -0.09543  0.02679  0.03757 -0.04051  0.03957
## 18  0.05728  0.21207  0.03727  0.01299 -0.05117 -0.01691  0.06300 -0.00861
## 19 -0.04350  0.03727  0.24318  0.02808 -0.02499  0.04084 -0.05518 -0.05344
## 20 -0.09543  0.01299  0.02808  0.36753  0.09274 -0.09739  0.05894 -0.05280
## 21  0.02679 -0.05117 -0.02499  0.09274  0.32674  0.11990 -0.07987 -0.06079
## 22  0.03757 -0.01691  0.04084 -0.09739  0.11990  0.32658  0.05312 -0.00836
## 23 -0.04051  0.06300 -0.05518  0.05894 -0.07987  0.05312  0.36461  0.12045
## 24  0.03957 -0.00861 -0.05344 -0.05280 -0.06079 -0.00836  0.12045  0.21663
## 25 -0.19058  0.01324  0.09555  0.00490 -0.02845  0.05010 -0.09884 -0.03959
## 26 -0.08674 -0.14086 -0.02790  0.16269  0.01306 -0.07869  0.08475 -0.10481
## 27  0.11630 -0.09420 -0.10681 -0.05590  0.19722 -0.03955 -0.09539  0.18106
## 28  0.11905  0.16155 -0.13596 -0.01836 -0.00323  0.11538  0.00579 -0.04932
## 29  0.03807  0.11237  0.15810 -0.15585 -0.03833  0.01560  0.11423 -0.00903
## 30  0.03157  0.00798  0.17890  0.11339 -0.12945 -0.04293 -0.03137  0.16906
##          25       26       27       28       29       30
## 1  -0.10280 -0.08953 -0.09273  0.04342 -0.04048 -0.10109
## 2  -0.14326 -0.09335 -0.03720 -0.08678  0.04348 -0.01790
## 3  -0.04322 -0.11103 -0.09638 -0.02840 -0.08683  0.03043
## 4  -0.03436 -0.02887 -0.09625 -0.08933 -0.03448 -0.07094
## 5  -0.17511 -0.02430 -0.04183 -0.09620 -0.08482 -0.05452
## 6   0.03720 -0.20207 -0.04172 -0.10232 -0.08730 -0.06510
## 7  -0.01419  0.01931 -0.19219 -0.06901 -0.09858 -0.06712
## 8  -0.01724 -0.03647  0.03430 -0.22473 -0.06520 -0.07091
## 9  -0.05835 -0.00317  0.00856  0.06481 -0.22893 -0.05603
## 10  0.12700 -0.08025  0.01963 -0.03901  0.06891 -0.18586
## 11  0.00820  0.09106 -0.08198 -0.05129 -0.02107  0.08400
## 12  0.17756  0.04169  0.05580 -0.08427 -0.05448 -0.03519
## 13 -0.01072  0.17206  0.06305  0.05461 -0.08632 -0.03594
## 14  0.10074 -0.00666  0.06937 -0.00182  0.07222 -0.13643
## 15 -0.04991  0.07938 -0.03964  0.02184  0.01329  0.05658
## 16 -0.10596  0.03376  0.04937  0.05088  0.01186 -0.06157
## 17 -0.19058 -0.08674  0.11630  0.11905  0.03807  0.03157
## 18  0.01324 -0.14086 -0.09420  0.16155  0.11237  0.00798
## 19  0.09555 -0.02790 -0.10681 -0.13596  0.15810  0.17890
## 20  0.00490  0.16269 -0.05590 -0.01836 -0.15585  0.11339
## 21 -0.02845  0.01306  0.19722 -0.00323 -0.03833 -0.12945
## 22  0.05010 -0.07869 -0.03955  0.11538  0.01560 -0.04293
## 23 -0.09884  0.08475 -0.09539  0.00579  0.11423 -0.03137
## 24 -0.03959 -0.10481  0.18106 -0.04932 -0.00903  0.16906
## 25  0.51674 -0.07003 -0.09090  0.13021 -0.06112  0.07318
## 26 -0.07003  0.55614 -0.07505 -0.01891  0.11642 -0.09163
## 27 -0.09090 -0.07505  0.50669 -0.09207 -0.00843  0.07686
## 28  0.13021 -0.01891 -0.09207  0.59141 -0.10477 -0.06318
## 29 -0.06112  0.11642 -0.00843 -0.10477  0.59345 -0.09196
## 30  0.07318 -0.09163  0.07686 -0.06318 -0.09196  0.58718
## 
## [[3]]
##           1        2        3        4        5        6        7        8
## 1   0.21024  0.15255  0.12415  0.04038  0.01827 -0.02284 -0.01575 -0.01354
## 2   0.15255  0.19247  0.13217  0.08321  0.05710 -0.00539 -0.03600 -0.03352
## 3   0.12415  0.13217  0.16484  0.12074  0.07284  0.03220 -0.01495 -0.04695
## 4   0.04038  0.08321  0.12074  0.16258  0.11554  0.07962  0.02580 -0.02340
## 5   0.01827  0.05710  0.07284  0.11554  0.15860  0.09315  0.07783  0.02471
## 6  -0.02284 -0.00539  0.03220  0.07962  0.09315  0.19290  0.11025  0.10055
## 7  -0.01575 -0.03600 -0.01495  0.02580  0.07783  0.11025  0.19907  0.11787
## 8  -0.01354 -0.03352 -0.04695 -0.02340  0.02471  0.10055  0.11787  0.20819
## 9   0.06475 -0.01448 -0.03201 -0.07695  0.00035 -0.00049  0.08557  0.09732
## 10  0.05446  0.01981 -0.04233 -0.04537 -0.08567  0.03140  0.00753  0.09533
## 11  0.04836  0.06399 -0.01398 -0.06234 -0.05511 -0.07851  0.04738  0.02913
## 12  0.05350  0.00235  0.03518  0.00447 -0.09518 -0.04988 -0.07954  0.04804
## 13 -0.00971  0.03948  0.00095  0.02857  0.00873 -0.08970 -0.05197 -0.08284
## 14 -0.01136  0.00087 -0.00544  0.03561 -0.02993  0.01040 -0.06722 -0.01804
## 15 -0.03028  0.01932 -0.01761 -0.00431  0.02041 -0.03376  0.02488 -0.04668
## 16  0.06920 -0.00698  0.02221 -0.01458 -0.00460 -0.05558 -0.06166 -0.00883
## 17  0.04530  0.07442  0.01869 -0.01851  0.03432 -0.04245 -0.08335 -0.10047
## 18  0.07480  0.03623  0.06629  0.01563 -0.02139 -0.00304 -0.05990 -0.10475
## 19 -0.08553  0.01680  0.03645  0.07082  0.01381  0.04348  0.00827 -0.04762
## 20 -0.07288 -0.10163  0.04052  0.06855  0.06468 -0.00963  0.02234 -0.01823
## 21 -0.14494 -0.10555 -0.06262  0.05588  0.08597  0.08800 -0.02126  0.00460
## 22 -0.14000 -0.11584 -0.11877 -0.04248  0.03004  0.11724  0.11790  0.01897
## 23 -0.01095 -0.10059 -0.10656 -0.12254 -0.03391 -0.01755  0.10465  0.10272
## 24 -0.01670 -0.03513 -0.07038 -0.14112 -0.07421 -0.02895 -0.03625  0.07596
## 25 -0.10377 -0.13997 -0.04559 -0.03639 -0.17062  0.03385 -0.01273 -0.01745
## 26 -0.08890 -0.09275 -0.11056 -0.03034 -0.02694 -0.19705  0.01662 -0.03489
## 27 -0.08976 -0.03910 -0.09464 -0.09668 -0.04361 -0.04414 -0.18684  0.03173
## 28  0.03829 -0.08354 -0.03082 -0.08826 -0.09524 -0.10035 -0.07028 -0.21915
## 29 -0.03729  0.03987 -0.08317 -0.03599 -0.08434 -0.09022 -0.09804 -0.06772
## 30 -0.10006 -0.02018  0.02915 -0.06814 -0.05559 -0.06352 -0.07022 -0.07104
##           9       10       11       12       13       14       15       16
## 1   0.06475  0.05446  0.04836  0.05350 -0.00971 -0.01136 -0.03028  0.06920
## 2  -0.01448  0.01981  0.06399  0.00235  0.03948  0.00087  0.01932 -0.00698
## 3  -0.03201 -0.04233 -0.01398  0.03518  0.00095 -0.00544 -0.01761  0.02221
## 4  -0.07695 -0.04537 -0.06234  0.00447  0.02857  0.03561 -0.00431 -0.01458
## 5   0.00035 -0.08567 -0.05511 -0.09518  0.00873 -0.02993  0.02041 -0.00460
## 6  -0.00049  0.03140 -0.07851 -0.04988 -0.08970  0.01040 -0.03376 -0.05558
## 7   0.08557  0.00753  0.04738 -0.07954 -0.05197 -0.06722  0.02488 -0.06166
## 8   0.09732  0.09533  0.02913  0.04804 -0.08284 -0.01804 -0.04668 -0.00883
## 9   0.21565  0.05727  0.10587  0.00163  0.03553 -0.06261  0.01042  0.00178
## 10  0.05727  0.22193  0.07186  0.10727 -0.00455  0.08140 -0.04036 -0.04237
## 11  0.10587  0.07186  0.25349  0.01544  0.11208 -0.05222  0.09143 -0.11263
## 12  0.00163  0.10727  0.01544  0.27334  0.02058  0.08483 -0.09441  0.06090
## 13  0.03553 -0.00455  0.11208  0.02058  0.26817  0.04915  0.09749 -0.09089
## 14 -0.06261  0.08140 -0.05222  0.08483  0.04915  0.11207 -0.03273 -0.00873
## 15  0.01042 -0.04036  0.09143 -0.09441  0.09749 -0.03273  0.09368 -0.08640
## 16  0.00178 -0.04237 -0.11263  0.06090 -0.09089 -0.00873 -0.08640  0.18191
## 17  0.00200 -0.06205 -0.02155 -0.13089  0.03824 -0.02477  0.04377  0.02266
## 18 -0.08959 -0.03391 -0.10790 -0.03482 -0.13269 -0.00344 -0.05045  0.08746
## 19 -0.17400 -0.06291 -0.00622 -0.04502 -0.04455 -0.00090  0.03524 -0.09329
## 20 -0.05287 -0.19545 -0.13534  0.05010 -0.04419 -0.04492 -0.04631  0.11165
## 21 -0.05993 -0.05862 -0.20115 -0.05245  0.03754  0.08081 -0.02346  0.01444
## 22  0.01722  0.00052 -0.03378 -0.21319 -0.03362 -0.02097  0.06161 -0.12044
## 23  0.06506 -0.00833 -0.01879 -0.06798 -0.20967 -0.10553 -0.04180  0.11315
## 24  0.07334  0.02363  0.03387  0.00481 -0.09503 -0.06193 -0.02912  0.03892
## 25 -0.05428  0.12226  0.01466  0.16778 -0.00428  0.09578 -0.04296 -0.10894
## 26 -0.00427 -0.07501  0.08785  0.04289  0.16646 -0.00430  0.07592  0.03277
## 27  0.01006  0.01707 -0.07905  0.05536  0.05948  0.06500 -0.03912  0.05090
## 28  0.05878 -0.03585 -0.04828 -0.08387  0.05519  0.00056  0.02343  0.04546
## 29 -0.22063  0.06108 -0.02235 -0.05177 -0.08561  0.06668  0.01159  0.01800
## 30 -0.06050 -0.18005  0.07379 -0.02947 -0.03834 -0.12811  0.05057 -0.05548
##          17       18       19       20       21       22       23       24
## 1   0.04530  0.07480 -0.08553 -0.07288 -0.14494 -0.14000 -0.01095 -0.01670
## 2   0.07442  0.03623  0.01680 -0.10163 -0.10555 -0.11584 -0.10059 -0.03513
## 3   0.01869  0.06629  0.03645  0.04052 -0.06262 -0.11877 -0.10656 -0.07038
## 4  -0.01851  0.01563  0.07082  0.06855  0.05588 -0.04248 -0.12254 -0.14112
## 5   0.03432 -0.02139  0.01381  0.06468  0.08597  0.03004 -0.03391 -0.07421
## 6  -0.04245 -0.00304  0.04348 -0.00963  0.08800  0.11724 -0.01755 -0.02895
## 7  -0.08335 -0.05990  0.00827  0.02234 -0.02126  0.11790  0.10465 -0.03625
## 8  -0.10047 -0.10475 -0.04762 -0.01823  0.00460  0.01897  0.10272  0.07596
## 9   0.00200 -0.08959 -0.17400 -0.05287 -0.05993  0.01722  0.06506  0.07334
## 10 -0.06205 -0.03391 -0.06291 -0.19545 -0.05862  0.00052 -0.00833  0.02363
## 11 -0.02155 -0.10790 -0.00622 -0.13534 -0.20115 -0.03378 -0.01879  0.03387
## 12 -0.13089 -0.03482 -0.04502  0.05010 -0.05245 -0.21319 -0.06798  0.00481
## 13  0.03824 -0.13269 -0.04455 -0.04419  0.03754 -0.03362 -0.20967 -0.09503
## 14 -0.02477 -0.00344 -0.00090 -0.04492  0.08081 -0.02097 -0.10553 -0.06193
## 15  0.04377 -0.05045  0.03524 -0.04631 -0.02346  0.06161 -0.04180 -0.02912
## 16  0.02266  0.08746 -0.09329  0.11165  0.01444 -0.12044  0.11315  0.03892
## 17  0.18663  0.06126 -0.04333 -0.08717  0.02565  0.03073 -0.03625  0.03838
## 18  0.06126  0.20410  0.04043  0.00745 -0.04881 -0.01200  0.05640 -0.00916
## 19 -0.04333  0.04043  0.23527  0.03524 -0.02328  0.03614 -0.05125 -0.05251
## 20 -0.08717  0.00745  0.03524  0.34684  0.09448 -0.08345  0.04999 -0.05260
## 21  0.02565 -0.04881 -0.02328  0.09448  0.31649  0.11862 -0.07328 -0.05794
## 22  0.03073 -0.01200  0.03614 -0.08345  0.11862  0.31327  0.06006 -0.00658
## 23 -0.03625  0.05640 -0.05125  0.04999 -0.07328  0.06006  0.35130  0.11737
## 24  0.03838 -0.00916 -0.05251 -0.05260 -0.05794 -0.00658  0.11737  0.21093
## 25 -0.18294  0.00732  0.09376  0.00085 -0.02844  0.05317 -0.09807 -0.03684
## 26 -0.08537 -0.13691 -0.02709  0.15607  0.01360 -0.07606  0.08267 -0.10013
## 27  0.11194 -0.08948 -0.10544 -0.05038  0.18813 -0.03987 -0.08788  0.17763
## 28  0.11785  0.15524 -0.12809 -0.02420 -0.00141  0.11469  0.00281 -0.04642
## 29  0.03821  0.11347  0.15022 -0.14340 -0.04011  0.01084  0.11552 -0.00703
## 30  0.02900  0.01216  0.17510  0.11389 -0.12098 -0.04401 -0.03078  0.16316
##          25       26       27       28       29       30
## 1  -0.10377 -0.08890 -0.08976  0.03829 -0.03729 -0.10006
## 2  -0.13997 -0.09275 -0.03910 -0.08354  0.03987 -0.02018
## 3  -0.04559 -0.11056 -0.09464 -0.03082 -0.08317  0.02915
## 4  -0.03639 -0.03034 -0.09668 -0.08826 -0.03599 -0.06814
## 5  -0.17062 -0.02694 -0.04361 -0.09524 -0.08434 -0.05559
## 6   0.03385 -0.19705 -0.04414 -0.10035 -0.09022 -0.06352
## 7  -0.01273  0.01662 -0.18684 -0.07028 -0.09804 -0.07022
## 8  -0.01745 -0.03489  0.03173 -0.21915 -0.06772 -0.07104
## 9  -0.05428 -0.00427  0.01006  0.05878 -0.22063 -0.06050
## 10  0.12226 -0.07501  0.01707 -0.03585  0.06108 -0.18005
## 11  0.01466  0.08785 -0.07905 -0.04828 -0.02235  0.07379
## 12  0.16778  0.04289  0.05536 -0.08387 -0.05177 -0.02947
## 13 -0.00428  0.16646  0.05948  0.05519 -0.08561 -0.03834
## 14  0.09578 -0.00430  0.06500  0.00056  0.06668 -0.12811
## 15 -0.04296  0.07592 -0.03912  0.02343  0.01159  0.05057
## 16 -0.10894  0.03277  0.05090  0.04546  0.01800 -0.05548
## 17 -0.18294 -0.08537  0.11194  0.11785  0.03821  0.02900
## 18  0.00732 -0.13691 -0.08948  0.15524  0.11347  0.01216
## 19  0.09376 -0.02709 -0.10544 -0.12809  0.15022  0.17510
## 20  0.00085  0.15607 -0.05038 -0.02420 -0.14340  0.11389
## 21 -0.02844  0.01360  0.18813 -0.00141 -0.04011 -0.12098
## 22  0.05317 -0.07606 -0.03987  0.11469  0.01084 -0.04401
## 23 -0.09807  0.08267 -0.08788  0.00281  0.11552 -0.03078
## 24 -0.03684 -0.10013  0.17763 -0.04642 -0.00703  0.16316
## 25  0.50088 -0.06388 -0.08598  0.12645 -0.06012  0.07649
## 26 -0.06388  0.54019 -0.06939 -0.01826  0.11672 -0.08965
## 27 -0.08598 -0.06939  0.48933 -0.08327 -0.01010  0.07811
## 28  0.12645 -0.01826 -0.08327  0.56998 -0.09197 -0.05952
## 29 -0.06012  0.11672 -0.01010 -0.09197  0.57149 -0.08386
## 30  0.07649 -0.08965  0.07811 -0.05952 -0.08386  0.56809
## 
## [[4]]
##           1        2        3        4        5        6        7        8
## 1   0.20699  0.15344  0.12278  0.04137  0.01960 -0.02161 -0.01540 -0.01338
## 2   0.15344  0.19044  0.13295  0.08360  0.05644 -0.00531 -0.03601 -0.03329
## 3   0.12278  0.13295  0.16339  0.12071  0.07365  0.03274 -0.01452 -0.04666
## 4   0.04137  0.08360  0.12071  0.16102  0.11539  0.07917  0.02651 -0.02304
## 5   0.01960  0.05644  0.07365  0.11539  0.15671  0.09373  0.07723  0.02536
## 6  -0.02161 -0.00531  0.03274  0.07917  0.09373  0.19022  0.11093  0.09965
## 7  -0.01540 -0.03601 -0.01452  0.02651  0.07723  0.11093  0.19605  0.11839
## 8  -0.01338 -0.03329 -0.04666 -0.02304  0.02536  0.09965  0.11839  0.20534
## 9   0.06318 -0.01408 -0.03249 -0.07500 -0.00052  0.00145  0.08415  0.09836
## 10  0.05498  0.01953 -0.04144 -0.04600 -0.08391  0.02866  0.00926  0.09395
## 11  0.05067  0.06092 -0.01260 -0.06087 -0.05704 -0.07694  0.04376  0.03066
## 12  0.05071  0.00572  0.03245  0.00292 -0.09175 -0.05022 -0.07593  0.04542
## 13 -0.00568  0.03732  0.00281  0.02743  0.00508 -0.08851 -0.05270 -0.07939
## 14 -0.01023  0.00137 -0.00493  0.03346 -0.02903  0.00813 -0.06434 -0.01856
## 15 -0.02718  0.01655 -0.01569 -0.00384  0.01756 -0.03285  0.02211 -0.04433
## 16  0.06396 -0.00353  0.01957 -0.01431 -0.00239 -0.05388 -0.05937 -0.01065
## 17  0.04626  0.07203  0.02014 -0.01726  0.03206 -0.04211 -0.08355 -0.09876
## 18  0.07102  0.03798  0.06452  0.01609 -0.01866 -0.00350 -0.05918 -0.10498
## 19 -0.08246  0.01491  0.03741  0.06997  0.01384  0.04184  0.00692 -0.04813
## 20 -0.07664 -0.09713  0.03694  0.06780  0.06581 -0.00656  0.02267 -0.01894
## 21 -0.14253 -0.10488 -0.06134  0.05356  0.08452  0.08602 -0.01811  0.00454
## 22 -0.13659 -0.11803 -0.11600 -0.04210  0.02806  0.11512  0.11548  0.02108
## 23 -0.01538 -0.09885 -0.10772 -0.12042 -0.03219 -0.01564  0.10271  0.10057
## 24 -0.01784 -0.03588 -0.07070 -0.13888 -0.07374 -0.02908 -0.03589  0.07372
## 25 -0.10426 -0.13724 -0.04758 -0.03823 -0.16673  0.03074 -0.01164 -0.01744
## 26 -0.08827 -0.09217 -0.11009 -0.03178 -0.02934 -0.19245  0.01421 -0.03349
## 27 -0.08731 -0.04069 -0.09321 -0.09700 -0.04517 -0.04621 -0.18190  0.02934
## 28  0.03391 -0.08084 -0.03280 -0.08731 -0.09450 -0.09871 -0.07144 -0.21394
## 29 -0.03482  0.03679 -0.08007 -0.03728 -0.08374 -0.09262 -0.09760 -0.07002
## 30 -0.09929 -0.02206  0.02779 -0.06569 -0.05632 -0.06220 -0.07279 -0.07136
##           9       10       11       12       13       14       15       16
## 1   0.06318  0.05498  0.05067  0.05071 -0.00568 -0.01023 -0.02718  0.06396
## 2  -0.01408  0.01953  0.06092  0.00572  0.03732  0.00137  0.01655 -0.00353
## 3  -0.03249 -0.04144 -0.01260  0.03245  0.00281 -0.00493 -0.01569  0.01957
## 4  -0.07500 -0.04600 -0.06087  0.00292  0.02743  0.03346 -0.00384 -0.01431
## 5  -0.00052 -0.08391 -0.05704 -0.09175  0.00508 -0.02903  0.01756 -0.00239
## 6   0.00145  0.02866 -0.07694 -0.05022 -0.08851  0.00813 -0.03285 -0.05388
## 7   0.08415  0.00926  0.04376 -0.07593 -0.05270 -0.06434  0.02211 -0.05937
## 8   0.09836  0.09395  0.03066  0.04542 -0.07939 -0.01856 -0.04433 -0.01065
## 9   0.21076  0.06091  0.10374  0.00433  0.03452 -0.05846  0.00890  0.00059
## 10  0.06091  0.21661  0.07466  0.10500 -0.00194  0.07711 -0.03796 -0.04172
## 11  0.10374  0.07466  0.24288  0.02487  0.10560 -0.04734  0.08275 -0.10344
## 12  0.00433  0.10500  0.02487  0.25947  0.02873  0.08079 -0.08434  0.05041
## 13  0.03452 -0.00194  0.10560  0.02873  0.25590  0.04944  0.08903 -0.08185
## 14 -0.05846  0.07711 -0.04734  0.08079  0.04944  0.10621 -0.02979 -0.00923
## 15  0.00890 -0.03796  0.08275 -0.08434  0.08903 -0.02979  0.08488 -0.07694
## 16  0.00059 -0.04172 -0.10344  0.05041 -0.08185 -0.00923 -0.07694  0.16817
## 17 -0.00039 -0.06078 -0.02559 -0.12317  0.03290 -0.02303  0.03864  0.02743
## 18 -0.08933 -0.03565 -0.10270 -0.03995 -0.12522 -0.00417 -0.04474  0.08091
## 19 -0.17050 -0.06471 -0.01064 -0.04222 -0.04618 -0.00147  0.03183 -0.08630
## 20 -0.05507 -0.19086 -0.12886  0.03965 -0.03848 -0.04325 -0.03907  0.09960
## 21 -0.05760 -0.06071 -0.19612 -0.05393  0.03398  0.07536 -0.02226  0.01453
## 22  0.01703 -0.00060 -0.03971 -0.20259 -0.04000 -0.02062  0.05422 -0.11010
## 23  0.06287 -0.00710 -0.01647 -0.07148 -0.20068 -0.10193 -0.03717  0.10469
## 24  0.07139  0.02404  0.03313  0.00475 -0.09163 -0.05940 -0.02805  0.03740
## 25 -0.05064  0.11806  0.01969  0.15977  0.00075  0.09146 -0.03747 -0.11053
## 26 -0.00511 -0.07031  0.08504  0.04378  0.16133 -0.00232  0.07284  0.03177
## 27  0.01120  0.01492 -0.07611  0.05460  0.05651  0.06116 -0.03832  0.05174
## 28  0.05343 -0.03318 -0.04591 -0.08283  0.05517  0.00256  0.02437  0.04132
## 29 -0.21328  0.05417 -0.02317 -0.04982 -0.08436  0.06186  0.01052  0.02272
## 30 -0.06435 -0.17497  0.06514 -0.02516 -0.03989 -0.12081  0.04578 -0.05058
##          17       18       19       20       21       22       23       24
## 1   0.04626  0.07102 -0.08246 -0.07664 -0.14253 -0.13659 -0.01538 -0.01784
## 2   0.07203  0.03798  0.01491 -0.09713 -0.10488 -0.11803 -0.09885 -0.03588
## 3   0.02014  0.06452  0.03741  0.03694 -0.06134 -0.11600 -0.10772 -0.07070
## 4  -0.01726  0.01609  0.06997  0.06780  0.05356 -0.04210 -0.12042 -0.13888
## 5   0.03206 -0.01866  0.01384  0.06581  0.08452  0.02806 -0.03219 -0.07374
## 6  -0.04211 -0.00350  0.04184 -0.00656  0.08602  0.11512 -0.01564 -0.02908
## 7  -0.08355 -0.05918  0.00692  0.02267 -0.01811  0.11548  0.10271 -0.03589
## 8  -0.09876 -0.10498 -0.04813 -0.01894  0.00454  0.02108  0.10057  0.07372
## 9  -0.00039 -0.08933 -0.17050 -0.05507 -0.05760  0.01703  0.06287  0.07139
## 10 -0.06078 -0.03565 -0.06471 -0.19086 -0.06071 -0.00060 -0.00710  0.02404
## 11 -0.02559 -0.10270 -0.01064 -0.12886 -0.19612 -0.03971 -0.01647  0.03313
## 12 -0.12317 -0.03995 -0.04222  0.03965 -0.05393 -0.20259 -0.07148  0.00475
## 13  0.03290 -0.12522 -0.04618 -0.03848  0.03398 -0.04000 -0.20068 -0.09163
## 14 -0.02303 -0.00417 -0.00147 -0.04325  0.07536 -0.02062 -0.10193 -0.05940
## 15  0.03864 -0.04474  0.03183 -0.03907 -0.02226  0.05422 -0.03717 -0.02805
## 16  0.02743  0.08091 -0.08630  0.09960  0.01453 -0.11010  0.10469  0.03740
## 17  0.18017  0.06422 -0.04266 -0.08055  0.02460  0.02531 -0.03299  0.03721
## 18  0.06422  0.19743  0.04283  0.00359 -0.04665 -0.00848  0.05103 -0.00962
## 19 -0.04266  0.04283  0.22833  0.04084 -0.02155  0.03255 -0.04818 -0.05168
## 20 -0.08055  0.00359  0.04084  0.32981  0.09578 -0.07223  0.04312 -0.05226
## 21  0.02460 -0.04665 -0.02155  0.09578  0.30716  0.11751 -0.06738 -0.05535
## 22  0.02531 -0.00848  0.03255 -0.07223  0.11751  0.30225  0.06540 -0.00501
## 23 -0.03299  0.05103 -0.04818  0.04312 -0.06738  0.06540  0.33972  0.11458
## 24  0.03721 -0.00962 -0.05168 -0.05226 -0.05535 -0.00501  0.11458  0.20559
## 25 -0.17640  0.00252  0.09163 -0.00200 -0.02834  0.05514 -0.09669 -0.03423
## 26 -0.08395 -0.13327 -0.02640  0.14992  0.01395 -0.07352  0.08078 -0.09571
## 27  0.10807 -0.08539 -0.10381 -0.04593  0.17993 -0.03971 -0.08137  0.17433
## 28  0.11633  0.14980 -0.12123 -0.02852  0.00003  0.11333  0.00068 -0.04364
## 29  0.03866  0.11397  0.14346 -0.13295 -0.04134  0.00716  0.11593 -0.00527
## 30  0.02715  0.01557  0.17175  0.11377 -0.11336 -0.04435 -0.03045  0.15771
##          25       26       27       28       29       30
## 1  -0.10426 -0.08827 -0.08731  0.03391 -0.03482 -0.09929
## 2  -0.13724 -0.09217 -0.04069 -0.08084  0.03679 -0.02206
## 3  -0.04758 -0.11009 -0.09321 -0.03280 -0.08007  0.02779
## 4  -0.03823 -0.03178 -0.09700 -0.08731 -0.03728 -0.06569
## 5  -0.16673 -0.02934 -0.04517 -0.09450 -0.08374 -0.05632
## 6   0.03074 -0.19245 -0.04621 -0.09871 -0.09262 -0.06220
## 7  -0.01164  0.01421 -0.18190 -0.07144 -0.09760 -0.07279
## 8  -0.01744 -0.03349  0.02934 -0.21394 -0.07002 -0.07136
## 9  -0.05064 -0.00511  0.01120  0.05343 -0.21328 -0.06435
## 10  0.11806 -0.07031  0.01492 -0.03318  0.05417 -0.17497
## 11  0.01969  0.08504 -0.07611 -0.04591 -0.02317  0.06514
## 12  0.15977  0.04378  0.05460 -0.08283 -0.04982 -0.02516
## 13  0.00075  0.16133  0.05651  0.05517 -0.08436 -0.03989
## 14  0.09146 -0.00232  0.06116  0.00256  0.06186 -0.12081
## 15 -0.03747  0.07284 -0.03832  0.02437  0.01052  0.04578
## 16 -0.11053  0.03177  0.05174  0.04132  0.02272 -0.05058
## 17 -0.17640 -0.08395  0.10807  0.11633  0.03866  0.02715
## 18  0.00252 -0.13327 -0.08539  0.14980  0.11397  0.01557
## 19  0.09163 -0.02640 -0.10381 -0.12123  0.14346  0.17175
## 20 -0.00200  0.14992 -0.04593 -0.02852 -0.13295  0.11377
## 21 -0.02834  0.01395  0.17993  0.00003 -0.04134 -0.11336
## 22  0.05514 -0.07352 -0.03971  0.11333  0.00716 -0.04435
## 23 -0.09669  0.08078 -0.08137  0.00068  0.11593 -0.03045
## 24 -0.03423 -0.09571  0.17433 -0.04364 -0.00527  0.15771
## 25  0.48662 -0.05829 -0.08148  0.12321 -0.05928  0.07890
## 26 -0.05829  0.52533 -0.06423 -0.01745  0.11672 -0.08752
## 27 -0.08148 -0.06423  0.47348 -0.07553 -0.01106  0.07915
## 28  0.12321 -0.01745 -0.07553  0.55062 -0.08084 -0.05607
## 29 -0.05928  0.11672 -0.01106 -0.08084  0.55193 -0.07638
## 30  0.07890 -0.08752  0.07915 -0.05607 -0.07638  0.55090
## 
## [[5]]
##           1        2        3        4        5        6        7        8
## 1   0.20417  0.15405  0.12165  0.04229  0.02071 -0.02051 -0.01510 -0.01316
## 2   0.15405  0.18868  0.13353  0.08395  0.05595 -0.00518 -0.03592 -0.03311
## 3   0.12165  0.13353  0.16213  0.12067  0.07433  0.03322 -0.01414 -0.04634
## 4   0.04229  0.08395  0.12067  0.15956  0.11523  0.07879  0.02713 -0.02267
## 5   0.02071  0.05595  0.07433  0.11523  0.15503  0.09425  0.07675  0.02588
## 6  -0.02051 -0.00518  0.03322  0.07879  0.09425  0.18776  0.11148  0.09881
## 7  -0.01510 -0.03592 -0.01414  0.02713  0.07675  0.11148  0.19329  0.11878
## 8  -0.01316 -0.03311 -0.04634 -0.02267  0.02588  0.09881  0.11878  0.20270
## 9   0.06176 -0.01372 -0.03287 -0.07323 -0.00128  0.00314  0.08292  0.09925
## 10  0.05541  0.01927 -0.04064 -0.04650 -0.08232  0.02623  0.01075  0.09275
## 11  0.05242  0.05842 -0.01157 -0.05957 -0.05851 -0.07549  0.04066  0.03188
## 12  0.04864  0.00839  0.03022  0.00154 -0.08894 -0.05051 -0.07284  0.04323
## 13 -0.00235  0.03568  0.00425  0.02631  0.00202 -0.08734 -0.05315 -0.07634
## 14 -0.00918  0.00180 -0.00447  0.03153 -0.02828  0.00613 -0.06180 -0.01894
## 15 -0.02473  0.01436 -0.01418 -0.00347  0.01525 -0.03200  0.01978 -0.04233
## 16  0.05966 -0.00084  0.01751 -0.01401 -0.00072 -0.05238 -0.05748 -0.01215
## 17  0.04683  0.07004  0.02129 -0.01612  0.03017 -0.04177 -0.08356 -0.09727
## 18  0.06781  0.03931  0.06308  0.01656 -0.01635 -0.00396 -0.05864 -0.10505
## 19 -0.07986  0.01337  0.03811  0.06916  0.01401  0.04039  0.00572 -0.04864
## 20 -0.07949 -0.09341  0.03399  0.06706  0.06650 -0.00388  0.02281 -0.01948
## 21 -0.14035 -0.10420 -0.06019  0.05145  0.08314  0.08425 -0.01528  0.00451
## 22 -0.13386 -0.11965 -0.11371 -0.04175  0.02650  0.11318  0.11337  0.02286
## 23 -0.01914 -0.09752 -0.10852 -0.11844 -0.03081 -0.01398  0.10079  0.09861
## 24 -0.01887 -0.03661 -0.07097 -0.13678 -0.07331 -0.02923 -0.03553  0.07162
## 25 -0.10443 -0.13490 -0.04929 -0.03991 -0.16331  0.02786 -0.01082 -0.01728
## 26 -0.08766 -0.09161 -0.10963 -0.03318 -0.03155 -0.18820  0.01203 -0.03225
## 27 -0.08523 -0.04205 -0.09201 -0.09722 -0.04656 -0.04801 -0.17732  0.02712
## 28  0.03009 -0.07854 -0.03446 -0.08647 -0.09390 -0.09734 -0.07249 -0.20906
## 29 -0.03289  0.03412 -0.07738 -0.03839 -0.08309 -0.09461 -0.09724 -0.07212
## 30 -0.09869 -0.02366  0.02641 -0.06351 -0.05680 -0.06109 -0.07495 -0.07180
##           9       10       11       12       13       14       15       16
## 1   0.06176  0.05541  0.05242  0.04864 -0.00235 -0.00918 -0.02473  0.05966
## 2  -0.01372  0.01927  0.05842  0.00839  0.03568  0.00180  0.01436 -0.00084
## 3  -0.03287 -0.04064 -0.01157  0.03022  0.00425 -0.00447 -0.01418  0.01751
## 4  -0.07323 -0.04650 -0.05957  0.00154  0.02631  0.03153 -0.00347 -0.01401
## 5  -0.00128 -0.08232 -0.05851 -0.08894  0.00202 -0.02828  0.01525 -0.00072
## 6   0.00314  0.02623 -0.07549 -0.05051 -0.08734  0.00613 -0.03200 -0.05238
## 7   0.08292  0.01075  0.04066 -0.07284 -0.05315 -0.06180  0.01978 -0.05748
## 8   0.09925  0.09275  0.03188  0.04323 -0.07634 -0.01894 -0.04233 -0.01215
## 9   0.20635  0.06408  0.10189  0.00675  0.03364 -0.05480  0.00759 -0.00049
## 10  0.06408  0.21183  0.07707  0.10306  0.00039  0.07334 -0.03587 -0.04109
## 11  0.10189  0.07707  0.23396  0.03244  0.10048 -0.04309  0.07567 -0.09601
## 12  0.00675  0.10306  0.03244  0.24795  0.03512  0.07732 -0.07619  0.04211
## 13  0.03364  0.00039  0.10048  0.03512  0.24538  0.04950  0.08213 -0.07462
## 14 -0.05480  0.07334 -0.04309  0.07732  0.04950  0.10102 -0.02730 -0.00955
## 15  0.00759 -0.03587  0.07567 -0.07619  0.08213 -0.02730  0.07772 -0.06936
## 16 -0.00049 -0.04109 -0.09601  0.04211 -0.07462 -0.00955 -0.06936  0.15691
## 17 -0.00258 -0.05968 -0.02870 -0.11674  0.02859 -0.02156  0.03454  0.03103
## 18 -0.08909 -0.03722 -0.09852 -0.04384 -0.11894 -0.00472 -0.04014  0.07569
## 19 -0.16729 -0.06630 -0.01432 -0.04020 -0.04722 -0.00198  0.02914 -0.08043
## 20 -0.05694 -0.18667 -0.12381  0.03120 -0.03428 -0.04171 -0.03343  0.08992
## 21 -0.05560 -0.06247 -0.19149 -0.05526  0.03069  0.07048 -0.02117  0.01451
## 22  0.01682 -0.00168 -0.04431 -0.19382 -0.04497 -0.02040  0.04830 -0.10170
## 23  0.06092 -0.00604 -0.01489 -0.07389 -0.19294 -0.09857 -0.03352  0.09771
## 24  0.06958  0.02437  0.03242  0.00474 -0.08848 -0.05708 -0.02708  0.03604
## 25 -0.04735  0.11429  0.02368  0.15305  0.00478  0.08763 -0.03304 -0.11121
## 26 -0.00575 -0.06607  0.08255  0.04445  0.15660 -0.00063  0.07009  0.03079
## 27  0.01205  0.01310 -0.07326  0.05366  0.05399  0.05776 -0.03737  0.05212
## 28  0.04864 -0.03092 -0.04398 -0.08144  0.05477  0.00425  0.02489  0.03808
## 29 -0.20672  0.04802 -0.02372 -0.04834 -0.08281  0.05764  0.00983  0.02645
## 30 -0.06770 -0.17048  0.05768 -0.02184 -0.04086 -0.11435  0.04189 -0.04651
##          17       18       19       20       21       22       23       24
## 1   0.04683  0.06781 -0.07986 -0.07949 -0.14035 -0.13386 -0.01914 -0.01887
## 2   0.07004  0.03931  0.01337 -0.09341 -0.10420 -0.11965 -0.09752 -0.03661
## 3   0.02129  0.06308  0.03811  0.03399 -0.06019 -0.11371 -0.10852 -0.07097
## 4  -0.01612  0.01656  0.06916  0.06706  0.05145 -0.04175 -0.11844 -0.13678
## 5   0.03017 -0.01635  0.01401  0.06650  0.08314  0.02650 -0.03081 -0.07331
## 6  -0.04177 -0.00396  0.04039 -0.00388  0.08425  0.11318 -0.01398 -0.02923
## 7  -0.08356 -0.05864  0.00572  0.02281 -0.01528  0.11337  0.10079 -0.03553
## 8  -0.09727 -0.10505 -0.04864 -0.01948  0.00451  0.02286  0.09861  0.07162
## 9  -0.00258 -0.08909 -0.16729 -0.05694 -0.05560  0.01682  0.06092  0.06958
## 10 -0.05968 -0.03722 -0.06630 -0.18667 -0.06247 -0.00168 -0.00604  0.02437
## 11 -0.02870 -0.09852 -0.01432 -0.12381 -0.19149 -0.04431 -0.01489  0.03242
## 12 -0.11674 -0.04384 -0.04020  0.03120 -0.05526 -0.19382 -0.07389  0.00474
## 13  0.02859 -0.11894 -0.04722 -0.03428  0.03069 -0.04497 -0.19294 -0.08848
## 14 -0.02156 -0.00472 -0.00198 -0.04171  0.07048 -0.02040 -0.09857 -0.05708
## 15  0.03454 -0.04014  0.02914 -0.03343 -0.02117  0.04830 -0.03352 -0.02708
## 16  0.03103  0.07569 -0.08043  0.08992  0.01451 -0.10170  0.09771  0.03604
## 17  0.17455  0.06646 -0.04169 -0.07509  0.02362  0.02091 -0.03043  0.03607
## 18  0.06646  0.19171  0.04469  0.00089 -0.04466 -0.00592  0.04653 -0.01003
## 19 -0.04169  0.04469  0.22214  0.04532 -0.01985  0.02974 -0.04571 -0.05091
## 20 -0.07509  0.00089  0.04532  0.31544  0.09675 -0.06297  0.03770 -0.05181
## 21  0.02362 -0.04466 -0.01985  0.09675  0.29861  0.11653 -0.06206 -0.05299
## 22  0.02091 -0.00592  0.02974 -0.06297  0.11653  0.29288  0.06960 -0.00360
## 23 -0.03043  0.04653 -0.04571  0.03770 -0.06206  0.06960  0.32944  0.11202
## 24  0.03607 -0.01003 -0.05091 -0.05181 -0.05299 -0.00360  0.11202  0.20060
## 25 -0.17068 -0.00148  0.08934 -0.00407 -0.02815  0.05640 -0.09495 -0.03177
## 26 -0.08252 -0.12989 -0.02579  0.14420  0.01415 -0.07108  0.07904 -0.09152
## 27  0.10457 -0.08176 -0.10204 -0.04227  0.17249 -0.03925 -0.07563  0.17115
## 28  0.11464  0.14502 -0.11517 -0.03178  0.00116  0.11158 -0.00084 -0.04099
## 29  0.03928  0.11407  0.13756 -0.12400 -0.04217  0.00423  0.11573 -0.00371
## 30  0.02580  0.01842  0.16873  0.11328 -0.10646 -0.04424 -0.03025  0.15266
##          25       26       27       28       29       30
## 1  -0.10443 -0.08766 -0.08523  0.03009 -0.03289 -0.09869
## 2  -0.13490 -0.09161 -0.04205 -0.07854  0.03412 -0.02366
## 3  -0.04929 -0.10963 -0.09201 -0.03446 -0.07738  0.02641
## 4  -0.03991 -0.03318 -0.09722 -0.08647 -0.03839 -0.06351
## 5  -0.16331 -0.03155 -0.04656 -0.09390 -0.08309 -0.05680
## 6   0.02786 -0.18820 -0.04801 -0.09734 -0.09461 -0.06109
## 7  -0.01082  0.01203 -0.17732 -0.07249 -0.09724 -0.07495
## 8  -0.01728 -0.03225  0.02712 -0.20906 -0.07212 -0.07180
## 9  -0.04735 -0.00575  0.01205  0.04864 -0.20672 -0.06770
## 10  0.11429 -0.06607  0.01310 -0.03092  0.04802 -0.17048
## 11  0.02368  0.08255 -0.07326 -0.04398 -0.02372  0.05768
## 12  0.15305  0.04445  0.05366 -0.08144 -0.04834 -0.02184
## 13  0.00478  0.15660  0.05399  0.05477 -0.08281 -0.04086
## 14  0.08763 -0.00063  0.05776  0.00425  0.05764 -0.11435
## 15 -0.03304  0.07009 -0.03737  0.02489  0.00983  0.04189
## 16 -0.11121  0.03079  0.05212  0.03808  0.02645 -0.04651
## 17 -0.17068 -0.08252  0.10457  0.11464  0.03928  0.02580
## 18 -0.00148 -0.12989 -0.08176  0.14502  0.11407  0.01842
## 19  0.08934 -0.02579 -0.10204 -0.11517  0.13756  0.16873
## 20 -0.00407  0.14420 -0.04227 -0.03178 -0.12400  0.11328
## 21 -0.02815  0.01415  0.17249  0.00116 -0.04217 -0.10646
## 22  0.05640 -0.07108 -0.03925  0.11158  0.00423 -0.04424
## 23 -0.09495  0.07904 -0.07563 -0.00084  0.11573 -0.03025
## 24 -0.03177 -0.09152  0.17115 -0.04099 -0.00371  0.15266
## 25  0.47363 -0.05319 -0.07730  0.12033 -0.05850  0.08064
## 26 -0.05319  0.51145 -0.05949 -0.01652  0.11649 -0.08531
## 27 -0.07730 -0.05949  0.45892 -0.06865 -0.01149  0.07998
## 28  0.12033 -0.01652 -0.06865  0.53298 -0.07106 -0.05279
## 29 -0.05850  0.11649 -0.01149 -0.07106  0.53432 -0.06950
## 30  0.08064 -0.08531  0.07998 -0.05279 -0.06950  0.53527
## 
## [[6]]
##           1        2        3        4        5        6        7        8
## 1   0.20053  0.15460  0.12028  0.04358  0.02209 -0.01904 -0.01472 -0.01276
## 2   0.15460  0.18641  0.13414  0.08444  0.05545 -0.00492 -0.03566 -0.03288
## 3   0.12028  0.13414  0.16048  0.12057  0.07515  0.03382 -0.01361 -0.04582
## 4   0.04358  0.08444  0.12057  0.15755  0.11496  0.07832  0.02793 -0.02210
## 5   0.02209  0.05545  0.07515  0.11496  0.15283  0.09494  0.07617  0.02651
## 6  -0.01904 -0.00492  0.03382  0.07832  0.09494  0.18441  0.11212  0.09767
## 7  -0.01472 -0.03566 -0.01361  0.02793  0.07617  0.11212  0.18955  0.11918
## 8  -0.01276 -0.03288 -0.04582 -0.02210  0.02651  0.09767  0.11918  0.19907
## 9   0.05990 -0.01323 -0.03330 -0.07083 -0.00228  0.00530  0.08135  0.10033
## 10  0.05591  0.01891 -0.03957 -0.04706 -0.08016  0.02306  0.01264  0.09119
## 11  0.05434  0.05541 -0.01046 -0.05789 -0.06008 -0.07352  0.03675  0.03332
## 12  0.04641  0.01149  0.02754 -0.00027 -0.08553 -0.05088 -0.06894  0.04051
## 13  0.00168  0.03388  0.00586  0.02468 -0.00179 -0.08568 -0.05345 -0.07233
## 14 -0.00775  0.00234 -0.00385  0.02898 -0.02733  0.00357 -0.05849 -0.01931
## 15 -0.02190  0.01183 -0.01245 -0.00306  0.01247 -0.03082  0.01689 -0.03981
## 16  0.05446  0.00222  0.01515 -0.01355  0.00107 -0.05041 -0.05514 -0.01399
## 17  0.04719  0.06757  0.02264 -0.01458  0.02784 -0.04128 -0.08334 -0.09537
## 18  0.06376  0.04074  0.06135  0.01723 -0.01346 -0.00462 -0.05807 -0.10496
## 19 -0.07658  0.01154  0.03882  0.06801  0.01442  0.03848  0.00414 -0.04939
## 20 -0.08256 -0.08886  0.03041  0.06596  0.06698 -0.00044  0.02279 -0.02006
## 21 -0.13742 -0.10317 -0.05868  0.04863  0.08119  0.08193 -0.01156  0.00451
## 22 -0.13065 -0.12133 -0.11088 -0.04129  0.02472  0.11052  0.11062  0.02509
## 23 -0.02384 -0.09605 -0.10924 -0.11570 -0.02919 -0.01185  0.09801  0.09595
## 24 -0.02027 -0.03765 -0.07129 -0.13386 -0.07272 -0.02949 -0.03500  0.06867
## 25 -0.10430 -0.13193 -0.05148 -0.04217 -0.15883  0.02392 -0.00995 -0.01686
## 26 -0.08676 -0.09083 -0.10895 -0.03521 -0.03454 -0.18241  0.00912 -0.03062
## 27 -0.08264 -0.04377 -0.09051 -0.09742 -0.04841 -0.05031 -0.17105  0.02407
## 28  0.02515 -0.07566 -0.03652 -0.08537 -0.09317 -0.09566 -0.07387 -0.20233
## 29 -0.03071  0.03065 -0.07395 -0.03979 -0.08210 -0.09699 -0.09685 -0.07490
## 30 -0.09797 -0.02566  0.02436 -0.06068 -0.05722 -0.05975 -0.07758 -0.07258
##           9       10       11       12       13       14       15       16
## 1   0.05990  0.05591  0.05434  0.04641  0.00168 -0.00775 -0.02190  0.05446
## 2  -0.01323  0.01891  0.05541  0.01149  0.03388  0.00234  0.01183  0.00222
## 3  -0.03330 -0.03957 -0.01046  0.02754  0.00586 -0.00385 -0.01245  0.01515
## 4  -0.07083 -0.04706 -0.05789 -0.00027  0.02468  0.02898 -0.00306 -0.01355
## 5  -0.00228 -0.08016 -0.06008 -0.08553 -0.00179 -0.02733  0.01247  0.00107
## 6   0.00530  0.02306 -0.07352 -0.05088 -0.08568  0.00357 -0.03082 -0.05041
## 7   0.08135  0.01264  0.03675 -0.06894 -0.05345 -0.05849  0.01689 -0.05514
## 8   0.10033  0.09119  0.03332  0.04051 -0.07233 -0.01931 -0.03981 -0.01399
## 9   0.20050  0.06814  0.09955  0.00993  0.03252 -0.05004  0.00592 -0.00194
## 10  0.06814  0.20552  0.08008  0.10061  0.00347  0.06847 -0.03319 -0.04019
## 11  0.09955  0.08008  0.22289  0.04134  0.09456 -0.03767  0.06717 -0.08720
## 12  0.00993  0.10061  0.04134  0.23380  0.04241  0.07290 -0.06650  0.03252
## 13  0.03252  0.00347  0.09456  0.04241  0.23200  0.04931  0.07383 -0.06612
## 14 -0.05004  0.06847 -0.03767  0.07290  0.04931  0.09422 -0.02420 -0.00979
## 15  0.00592 -0.03319  0.06717 -0.06650  0.07383 -0.02420  0.06915 -0.06043
## 16 -0.00194 -0.04019 -0.08720  0.03252 -0.06612 -0.00979 -0.06043  0.14331
## 17 -0.00554 -0.05829 -0.03215 -0.10885  0.02350 -0.01971  0.02975  0.03493
## 18 -0.08877 -0.03933 -0.09360 -0.04811 -0.11114 -0.00534 -0.03471  0.06960
## 19 -0.16293 -0.06837 -0.01887 -0.03813 -0.04810 -0.00267  0.02600 -0.07315
## 20 -0.05925 -0.18101 -0.11804  0.02116 -0.02989 -0.03962 -0.02703  0.07851
## 21 -0.05310 -0.06459 -0.18523 -0.05699  0.02619  0.06405 -0.01972  0.01437
## 22  0.01648 -0.00321 -0.04949 -0.18308 -0.05058 -0.02023  0.04134 -0.09164
## 23  0.05835 -0.00473 -0.01339 -0.07617 -0.18304 -0.09398 -0.02930  0.08920
## 24  0.06711  0.02475  0.03145  0.00478 -0.08415 -0.05392 -0.02576  0.03423
## 25 -0.04297  0.10931  0.02831  0.14470  0.00949  0.08264 -0.02777 -0.11113
## 26 -0.00640 -0.06041  0.07930  0.04515  0.15014  0.00145  0.06643  0.02939
## 27  0.01293  0.01085 -0.06920  0.05210  0.05080  0.05335 -0.03584  0.05213
## 28  0.04235 -0.02814 -0.04162 -0.07899  0.05377  0.00632  0.02520  0.03436
## 29 -0.19811  0.03998 -0.02425 -0.04671 -0.08022  0.05224  0.00924  0.03071
## 30 -0.07194 -0.16464  0.04818 -0.01819 -0.04162 -0.10591  0.03725 -0.04150
##          17       18       19       20       21       22       23       24
## 1   0.04719  0.06376 -0.07658 -0.08256 -0.13742 -0.13065 -0.02384 -0.02027
## 2   0.06757  0.04074  0.01154 -0.08886 -0.10317 -0.12133 -0.09605 -0.03765
## 3   0.02264  0.06135  0.03882  0.03041 -0.05868 -0.11088 -0.10924 -0.07129
## 4  -0.01458  0.01723  0.06801  0.06596  0.04863 -0.04129 -0.11570 -0.13386
## 5   0.02784 -0.01346  0.01442  0.06698  0.08119  0.02472 -0.02919 -0.07272
## 6  -0.04128 -0.00462  0.03848 -0.00044  0.08193  0.11052 -0.01185 -0.02949
## 7  -0.08334 -0.05807  0.00414  0.02279 -0.01156  0.11062  0.09801 -0.03500
## 8  -0.09537 -0.10496 -0.04939 -0.02006  0.00451  0.02509  0.09595  0.06867
## 9  -0.00554 -0.08877 -0.16293 -0.05925 -0.05310  0.01648  0.05835  0.06711
## 10 -0.05829 -0.03933 -0.06837 -0.18101 -0.06459 -0.00321 -0.00473  0.02475
## 11 -0.03215 -0.09360 -0.01887 -0.11804 -0.18523 -0.04949 -0.01339  0.03145
## 12 -0.10885 -0.04811 -0.03813  0.02116 -0.05699 -0.18308 -0.07617  0.00478
## 13  0.02350 -0.11114 -0.04810 -0.02989  0.02619 -0.05058 -0.18304 -0.08415
## 14 -0.01971 -0.00534 -0.00267 -0.03962  0.06405 -0.02023 -0.09398 -0.05392
## 15  0.02975 -0.03471  0.02600 -0.02703 -0.01972  0.04134 -0.02930 -0.02576
## 16  0.03493  0.06960 -0.07315  0.07851  0.01437 -0.09164  0.08920  0.03423
## 17  0.16727  0.06890 -0.03992 -0.06841  0.02228  0.01564 -0.02749  0.03443
## 18  0.06890  0.18440  0.04680 -0.00174 -0.04195 -0.00328  0.04097 -0.01055
## 19 -0.03992  0.04680  0.21393  0.05054 -0.01736  0.02653 -0.04278 -0.04985
## 20 -0.06841 -0.00174  0.05054  0.29751  0.09774 -0.05167  0.03151 -0.05103
## 21  0.02228 -0.04195 -0.01736  0.09774  0.28704  0.11523 -0.05496 -0.04978
## 22  0.01564 -0.00328  0.02653 -0.05167  0.11523  0.28106  0.07441 -0.00175
## 23 -0.02749  0.04097 -0.04278  0.03151 -0.05496  0.07441  0.31591  0.10854
## 24  0.03443 -0.01055 -0.04985 -0.05103 -0.04978 -0.00175  0.10854  0.19366
## 25 -0.16324 -0.00638  0.08577 -0.00620 -0.02777  0.05741 -0.09195 -0.02833
## 26 -0.08040 -0.12524 -0.02502  0.13634  0.01426 -0.06762  0.07669 -0.08563
## 27  0.09988 -0.07701 -0.09926 -0.03784  0.16252 -0.03821 -0.06815  0.16661
## 28  0.11197  0.13877 -0.10723 -0.03524  0.00244  0.10854 -0.00236 -0.03726
## 29  0.04034  0.11377  0.12999 -0.11270 -0.04283  0.00084  0.11468 -0.00166
## 30  0.02443  0.02196  0.16465  0.11215 -0.09725 -0.04351 -0.03003  0.14575
##          25       26       27       28       29       30
## 1  -0.10430 -0.08676 -0.08264  0.02515 -0.03071 -0.09797
## 2  -0.13193 -0.09083 -0.04377 -0.07566  0.03065 -0.02566
## 3  -0.05148 -0.10895 -0.09051 -0.03652 -0.07395  0.02436
## 4  -0.04217 -0.03521 -0.09742 -0.08537 -0.03979 -0.06068
## 5  -0.15883 -0.03454 -0.04841 -0.09317 -0.08210 -0.05722
## 6   0.02392 -0.18241 -0.05031 -0.09566 -0.09699 -0.05975
## 7  -0.00995  0.00912 -0.17105 -0.07387 -0.09685 -0.07758
## 8  -0.01686 -0.03062  0.02407 -0.20233 -0.07490 -0.07258
## 9  -0.04297 -0.00640  0.01293  0.04235 -0.19811 -0.07194
## 10  0.10931 -0.06041  0.01085 -0.02814  0.03998 -0.16464
## 11  0.02831  0.07930 -0.06920 -0.04162 -0.02425  0.04818
## 12  0.14470  0.04515  0.05210 -0.07899 -0.04671 -0.01819
## 13  0.00949  0.15014  0.05080  0.05377 -0.08022 -0.04162
## 14  0.08264  0.00145  0.05335  0.00632  0.05224 -0.10591
## 15 -0.02777  0.06643 -0.03584  0.02520  0.00924  0.03725
## 16 -0.11113  0.02939  0.05213  0.03436  0.03071 -0.04150
## 17 -0.16324 -0.08040  0.09988  0.11197  0.04034  0.02443
## 18 -0.00638 -0.12524 -0.07701  0.13877  0.11377  0.02196
## 19  0.08577 -0.02502 -0.09926 -0.10723  0.12999  0.16465
## 20 -0.00620  0.13634 -0.03784 -0.03524 -0.11270  0.11215
## 21 -0.02777  0.01426  0.16252  0.00244 -0.04283 -0.09725
## 22  0.05741 -0.06762 -0.03821  0.10854  0.00084 -0.04351
## 23 -0.09195  0.07669 -0.06815 -0.00236  0.11468 -0.03003
## 24 -0.02833 -0.08563  0.16661 -0.03726 -0.00166  0.14575
## 25  0.45605 -0.04629 -0.07154  0.11651 -0.05737  0.08237
## 26 -0.04629  0.49224 -0.05306 -0.01499  0.11581 -0.08192
## 27 -0.07154 -0.05306  0.43914 -0.05962 -0.01146  0.08091
## 28  0.11651 -0.01499 -0.05962  0.50919 -0.05839 -0.04813
## 29 -0.05737  0.11581 -0.01146 -0.05839  0.51087 -0.06016
## 30  0.08237 -0.08192  0.08091 -0.04813 -0.06016  0.51424
hatr(ridge)[[2]]
##           1        2        3        4        5        6        7        8
## 1   0.21408  0.15125  0.12588  0.03933  0.01662 -0.02422 -0.01621 -0.01360
## 2   0.15125  0.19488  0.13113  0.08277  0.05803 -0.00539 -0.03584 -0.03384
## 3   0.12588  0.13113  0.16652  0.12075  0.07182  0.03155 -0.01546 -0.04717
## 4   0.03933  0.08277  0.12075  0.16426  0.11565  0.08014  0.02498 -0.02373
## 5   0.01662  0.05803  0.07182  0.11565  0.16078  0.09252  0.07858  0.02391
## 6  -0.02422 -0.00539  0.03155  0.08014  0.09252  0.19584  0.10944  0.10155
## 7  -0.01621 -0.03584 -0.01546  0.02498  0.07858  0.10944  0.20242  0.11718
## 8  -0.01360 -0.03384 -0.04717 -0.02373  0.02391  0.10155  0.11718  0.21129
## 9   0.06653 -0.01492 -0.03143 -0.07910  0.00133 -0.00273  0.08723  0.09608
## 10  0.05382  0.02011 -0.04330 -0.04459 -0.08761  0.03452  0.00552  0.09691
## 11  0.04524  0.06786 -0.01587 -0.06403 -0.05250 -0.08021  0.05170  0.02718
## 12  0.05734 -0.00201  0.03863  0.00624 -0.09946 -0.04953 -0.08385  0.05122
## 13 -0.01476  0.04240 -0.00152  0.02971  0.01317 -0.09091 -0.05082 -0.08682
## 14 -0.01257  0.00025 -0.00599  0.03802 -0.03102  0.01302 -0.07051 -0.01733
## 15 -0.03431  0.02293 -0.02012 -0.00491  0.02400 -0.03471  0.02824 -0.04951
## 16  0.07576 -0.01150  0.02566 -0.01481 -0.00762 -0.05754 -0.06448 -0.00656
## 17  0.04376  0.07737  0.01684 -0.01988  0.03709 -0.04278 -0.08286 -0.10250
## 18  0.07937  0.03385  0.06852  0.01518 -0.02470 -0.00261 -0.06090 -0.10428
## 19 -0.08924  0.01919  0.03511  0.07172  0.01401  0.04536  0.00983 -0.04714
## 20 -0.06782 -0.10723  0.04500  0.06932  0.06288 -0.01319  0.02169 -0.01724
## 21 -0.14763 -0.10618 -0.06406  0.05844  0.08748  0.09026 -0.02478  0.00472
## 22 -0.14439 -0.11282 -0.12219 -0.04293  0.03266  0.11958  0.12076  0.01643
## 23 -0.00559 -0.10293 -0.10488 -0.12480 -0.03613 -0.01978  0.10655  0.10514
## 24 -0.01543 -0.03435 -0.06999 -0.14352 -0.07472 -0.02885 -0.03663  0.07835
## 25 -0.10280 -0.14326 -0.04322 -0.03436 -0.17511  0.03720 -0.01419 -0.01724
## 26 -0.08953 -0.09335 -0.11103 -0.02887 -0.02430 -0.20207  0.01931 -0.03647
## 27 -0.09273 -0.03720 -0.09638 -0.09625 -0.04183 -0.04172 -0.19219  0.03430
## 28  0.04342 -0.08678 -0.02840 -0.08933 -0.09620 -0.10232 -0.06901 -0.22473
## 29 -0.04048  0.04348 -0.08683 -0.03448 -0.08482 -0.08730 -0.09858 -0.06520
## 30 -0.10109 -0.01790  0.03043 -0.07094 -0.05452 -0.06510 -0.06712 -0.07091
##           9       10       11       12       13       14       15       16
## 1   0.06653  0.05382  0.04524  0.05734 -0.01476 -0.01257 -0.03431  0.07576
## 2  -0.01492  0.02011  0.06786 -0.00201  0.04240  0.00025  0.02293 -0.01150
## 3  -0.03143 -0.04330 -0.01587  0.03863 -0.00152 -0.00599 -0.02012  0.02566
## 4  -0.07910 -0.04459 -0.06403  0.00624  0.02971  0.03802 -0.00491 -0.01481
## 5   0.00133 -0.08761 -0.05250 -0.09946  0.01317 -0.03102  0.02400 -0.00762
## 6  -0.00273  0.03452 -0.08021 -0.04953 -0.09091  0.01302 -0.03471 -0.05754
## 7   0.08723  0.00552  0.05170 -0.08385 -0.05082 -0.07051  0.02824 -0.06448
## 8   0.09608  0.09691  0.02718  0.05122 -0.08682 -0.01733 -0.04951 -0.00656
## 9   0.22114  0.05307  0.10836 -0.00142  0.03671 -0.06736  0.01219  0.00308
## 10  0.05307  0.22792  0.06854  0.10995 -0.00749  0.08634 -0.04315 -0.04302
## 11  0.10836  0.06854  0.26642  0.00340  0.12050 -0.05793  0.10233 -0.12435
## 12 -0.00142  0.10995  0.00340  0.29048  0.00993  0.08959 -0.10717  0.07451
## 13  0.03671 -0.00749  0.12050  0.00993  0.28283  0.04853  0.10814 -0.10251
## 14 -0.06736  0.08634 -0.05793  0.08959  0.04853  0.11872 -0.03627 -0.00793
## 15  0.01219 -0.04315  0.10233 -0.10717  0.10814 -0.03627  0.10477 -0.09854
## 16  0.00308 -0.04302 -0.12435  0.07451 -0.10251 -0.00793 -0.09854  0.19916
## 17  0.00464 -0.06354 -0.01615 -0.14043  0.04504 -0.02685  0.05037  0.01620
## 18 -0.08987 -0.03197 -0.11458 -0.02791 -0.14183 -0.00247 -0.05774  0.09593
## 19 -0.17785 -0.06087 -0.00076 -0.04896 -0.04206 -0.00030  0.03966 -0.10185
## 20 -0.05026 -0.20049 -0.14392  0.06342 -0.05212 -0.04668 -0.05590  0.12703
## 21 -0.06267 -0.05609 -0.20664 -0.05080  0.04143  0.08696 -0.02477  0.01419
## 22  0.01738  0.00169 -0.02593 -0.22635 -0.02521 -0.02152  0.07111 -0.13351
## 23  0.06754 -0.00979 -0.02222 -0.06288 -0.22038 -0.10941 -0.04785  0.12368
## 24  0.07546  0.02312  0.03465  0.00496 -0.09873 -0.06468 -0.03030  0.04065
## 25 -0.05835  0.12700  0.00820  0.17756 -0.01072  0.10074 -0.04991 -0.10596
## 26 -0.00317 -0.08025  0.09106  0.04169  0.17206 -0.00666  0.07938  0.03376
## 27  0.00856  0.01963 -0.08198  0.05580  0.06305  0.06937 -0.03964  0.04937
## 28  0.06481 -0.03901 -0.05129 -0.08427  0.05461 -0.00182  0.02184  0.05088
## 29 -0.22893  0.06891 -0.02107 -0.05448 -0.08632  0.07222  0.01329  0.01186
## 30 -0.05603 -0.18586  0.08400 -0.03519 -0.03594 -0.13643  0.05658 -0.06157
##          17       18       19       20       21       22       23       24
## 1   0.04376  0.07937 -0.08924 -0.06782 -0.14763 -0.14439 -0.00559 -0.01543
## 2   0.07737  0.03385  0.01919 -0.10723 -0.10618 -0.11282 -0.10293 -0.03435
## 3   0.01684  0.06852  0.03511  0.04500 -0.06406 -0.12219 -0.10488 -0.06999
## 4  -0.01988  0.01518  0.07172  0.06932  0.05844 -0.04293 -0.12480 -0.14352
## 5   0.03709 -0.02470  0.01401  0.06288  0.08748  0.03266 -0.03613 -0.07472
## 6  -0.04278 -0.00261  0.04536 -0.01319  0.09026  0.11958 -0.01978 -0.02885
## 7  -0.08286 -0.06090  0.00983  0.02169 -0.02478  0.12076  0.10655 -0.03663
## 8  -0.10250 -0.10428 -0.04714 -0.01724  0.00472  0.01643  0.10514  0.07835
## 9   0.00464 -0.08987 -0.17785 -0.05026 -0.06267  0.01738  0.06754  0.07546
## 10 -0.06354 -0.03197 -0.06087 -0.20049 -0.05609  0.00169 -0.00979  0.02312
## 11 -0.01615 -0.11458 -0.00076 -0.14392 -0.20664 -0.02593 -0.02222  0.03465
## 12 -0.14043 -0.02791 -0.04896  0.06342 -0.05080 -0.22635 -0.06288  0.00496
## 13  0.04504 -0.14183 -0.04206 -0.05212  0.04143 -0.02521 -0.22038 -0.09873
## 14 -0.02685 -0.00247 -0.00030 -0.04668  0.08696 -0.02152 -0.10941 -0.06468
## 15  0.05037 -0.05774  0.03966 -0.05590 -0.02477  0.07111 -0.04785 -0.03030
## 16  0.01620  0.09593 -0.10185  0.12703  0.01419 -0.13351  0.12368  0.04065
## 17  0.19423  0.05728 -0.04350 -0.09543  0.02679  0.03757 -0.04051  0.03957
## 18  0.05728  0.21207  0.03727  0.01299 -0.05117 -0.01691  0.06300 -0.00861
## 19 -0.04350  0.03727  0.24318  0.02808 -0.02499  0.04084 -0.05518 -0.05344
## 20 -0.09543  0.01299  0.02808  0.36753  0.09274 -0.09739  0.05894 -0.05280
## 21  0.02679 -0.05117 -0.02499  0.09274  0.32674  0.11990 -0.07987 -0.06079
## 22  0.03757 -0.01691  0.04084 -0.09739  0.11990  0.32658  0.05312 -0.00836
## 23 -0.04051  0.06300 -0.05518  0.05894 -0.07987  0.05312  0.36461  0.12045
## 24  0.03957 -0.00861 -0.05344 -0.05280 -0.06079 -0.00836  0.12045  0.21663
## 25 -0.19058  0.01324  0.09555  0.00490 -0.02845  0.05010 -0.09884 -0.03959
## 26 -0.08674 -0.14086 -0.02790  0.16269  0.01306 -0.07869  0.08475 -0.10481
## 27  0.11630 -0.09420 -0.10681 -0.05590  0.19722 -0.03955 -0.09539  0.18106
## 28  0.11905  0.16155 -0.13596 -0.01836 -0.00323  0.11538  0.00579 -0.04932
## 29  0.03807  0.11237  0.15810 -0.15585 -0.03833  0.01560  0.11423 -0.00903
## 30  0.03157  0.00798  0.17890  0.11339 -0.12945 -0.04293 -0.03137  0.16906
##          25       26       27       28       29       30
## 1  -0.10280 -0.08953 -0.09273  0.04342 -0.04048 -0.10109
## 2  -0.14326 -0.09335 -0.03720 -0.08678  0.04348 -0.01790
## 3  -0.04322 -0.11103 -0.09638 -0.02840 -0.08683  0.03043
## 4  -0.03436 -0.02887 -0.09625 -0.08933 -0.03448 -0.07094
## 5  -0.17511 -0.02430 -0.04183 -0.09620 -0.08482 -0.05452
## 6   0.03720 -0.20207 -0.04172 -0.10232 -0.08730 -0.06510
## 7  -0.01419  0.01931 -0.19219 -0.06901 -0.09858 -0.06712
## 8  -0.01724 -0.03647  0.03430 -0.22473 -0.06520 -0.07091
## 9  -0.05835 -0.00317  0.00856  0.06481 -0.22893 -0.05603
## 10  0.12700 -0.08025  0.01963 -0.03901  0.06891 -0.18586
## 11  0.00820  0.09106 -0.08198 -0.05129 -0.02107  0.08400
## 12  0.17756  0.04169  0.05580 -0.08427 -0.05448 -0.03519
## 13 -0.01072  0.17206  0.06305  0.05461 -0.08632 -0.03594
## 14  0.10074 -0.00666  0.06937 -0.00182  0.07222 -0.13643
## 15 -0.04991  0.07938 -0.03964  0.02184  0.01329  0.05658
## 16 -0.10596  0.03376  0.04937  0.05088  0.01186 -0.06157
## 17 -0.19058 -0.08674  0.11630  0.11905  0.03807  0.03157
## 18  0.01324 -0.14086 -0.09420  0.16155  0.11237  0.00798
## 19  0.09555 -0.02790 -0.10681 -0.13596  0.15810  0.17890
## 20  0.00490  0.16269 -0.05590 -0.01836 -0.15585  0.11339
## 21 -0.02845  0.01306  0.19722 -0.00323 -0.03833 -0.12945
## 22  0.05010 -0.07869 -0.03955  0.11538  0.01560 -0.04293
## 23 -0.09884  0.08475 -0.09539  0.00579  0.11423 -0.03137
## 24 -0.03959 -0.10481  0.18106 -0.04932 -0.00903  0.16906
## 25  0.51674 -0.07003 -0.09090  0.13021 -0.06112  0.07318
## 26 -0.07003  0.55614 -0.07505 -0.01891  0.11642 -0.09163
## 27 -0.09090 -0.07505  0.50669 -0.09207 -0.00843  0.07686
## 28  0.13021 -0.01891 -0.09207  0.59141 -0.10477 -0.06318
## 29 -0.06112  0.11642 -0.00843 -0.10477  0.59345 -0.09196
## 30  0.07318 -0.09163  0.07686 -0.06318 -0.09196  0.58718
diag(hatr(ridge)[[2]])
##       1       2       3       4       5       6       7       8       9      10 
## 0.21408 0.19488 0.16652 0.16426 0.16078 0.19584 0.20242 0.21129 0.22114 0.22792 
##      11      12      13      14      15      16      17      18      19      20 
## 0.26642 0.29048 0.28283 0.11872 0.10477 0.19916 0.19423 0.21207 0.24318 0.36753 
##      21      22      23      24      25      26      27      28      29      30 
## 0.32674 0.32658 0.36461 0.21663 0.51674 0.55614 0.50669 0.59141 0.59345 0.58718
diag(hatr(lmridge(C ~ ., dados, K = lambdas))[[2]])
##       1       2       3       4       5       6       7       8       9      10 
## 0.21408 0.19488 0.16652 0.16426 0.16078 0.19584 0.20242 0.21129 0.22114 0.22792 
##      11      12      13      14      15      16      17      18      19      20 
## 0.26642 0.29048 0.28283 0.11872 0.10477 0.19916 0.19423 0.21207 0.24318 0.36753 
##      21      22      23      24      25      26      27      28      29      30 
## 0.32674 0.32658 0.36461 0.21663 0.51674 0.55614 0.50669 0.59141 0.59345 0.58718
vif(ridge)
##                 Y    Ylag1    Ylag2    Ylag3    Ylag4    Ylag5     Ylag6
## k=0      44.83858 80.89668 83.11378 83.42578 87.16720 86.79350 151.89742
## k=2e-04  42.98477 76.23658 78.86374 79.12399 82.01819 81.39158 136.27872
## k=6e-04  39.77510 68.32764 71.47625 71.68833 73.39192 72.47416 112.52817
## k=0.001  37.07067 61.84348 65.26310 65.46172 66.40092 65.36713  95.40655
## k=0.0014 34.74438 56.41507 59.95815 60.15560 60.58693 59.53471  82.52616
## k=0.002  31.78691 49.73474 53.30547 53.50549 53.46072 52.47486  68.29057
##              Ylag7    Ylag8
## k=0      208.04782 89.48488
## k=2e-04  181.45348 81.30048
## k=6e-04  142.08160 68.73711
## k=0.001  114.75646 59.56211
## k=0.0014  94.97609 52.57115
## k=0.002   74.11412 44.72628
vcov(ridge)
## $`K=0`
##                 Y       Ylag1       Ylag2       Ylag3       Ylag4      Ylag5
## Y      173.297111 -159.112342    5.615915  -28.705909   49.565856  -13.53264
## Ylag1 -159.112342  312.658432 -164.825137    7.451599  -55.774138   61.18914
## Ylag2    5.615915 -164.825137  321.227342 -138.833828   -6.906527  -54.72858
## Ylag3  -28.705909    7.451599 -138.833828  322.433199 -157.288056   28.85478
## Ylag4   49.565856  -55.774138   -6.906527 -157.288056  336.893455 -173.93390
## Ylag5  -13.532636   61.189138  -54.728579   28.854779 -173.933900  335.44914
## Ylag6  -27.215367   59.933099    3.476099 -120.103638   71.487297 -227.93505
## Ylag7   82.340110 -135.200641   99.270787   69.344494 -140.812051  102.52815
## Ylag8  -81.064950   74.337405  -64.681562   17.063506   77.345935  -57.18907
##             Ylag6      Ylag7      Ylag8
## Y      -27.215367   82.34011  -81.06495
## Ylag1   59.933099 -135.20064   74.33741
## Ylag2    3.476099   99.27079  -64.68156
## Ylag3 -120.103638   69.34449   17.06351
## Ylag4   71.487297 -140.81205   77.34594
## Ylag5 -227.935052  102.52815  -57.18907
## Ylag6  587.069972 -459.07975  111.93520
## Ylag7 -459.079746  804.08623 -422.29100
## Ylag8  111.935197 -422.29100  345.85108
## 
## $`K=2e-04`
##                 Y       Ylag1       Ylag2       Ylag3       Ylag4      Ylag5
## Y      166.107224 -149.268311    1.184742  -26.989820   47.298310  -12.67540
## Ylag1 -149.268311  294.603139 -152.427209    4.697914  -53.001775   58.05445
## Ylag2    1.184742 -152.427209  304.755355 -130.278562   -8.680036  -51.08753
## Ylag3  -26.989820    4.697914 -130.278562  305.761032 -145.049100   20.56119
## Ylag4   47.298310  -53.001775   -8.680036 -145.049100  316.945185 -158.58857
## Ylag5  -12.675404   58.054450  -51.087533   20.561187 -158.588565  314.52375
## Ylag6  -21.114261   49.945647    6.084082 -105.420767   53.698279 -202.01435
## Ylag7   69.407229 -114.285178   85.609102   57.052258 -118.327791   78.96223
## Ylag8  -72.765935   62.325375  -55.509186   19.871348   66.272233  -47.05667
##             Ylag6      Ylag7      Ylag8
## Y      -21.114261   69.40723  -72.76594
## Ylag1   49.945647 -114.28518   62.32537
## Ylag2    6.084082   85.60910  -55.50919
## Ylag3 -105.420767   57.05226   19.87135
## Ylag4   53.698279 -118.32779   66.27223
## Ylag5 -202.014346   78.96223  -47.05667
## Ylag6  526.625622 -390.78744   82.58459
## Ylag7 -390.787442  701.19570 -368.61776
## Ylag8   82.584587 -368.61776  314.17171
## 
## $`K=6e-04`
##                 Y        Ylag1       Ylag2        Ylag3      Ylag4      Ylag5
## Y      153.565727 -132.5723868   -5.687403  -23.7939677   42.61437  -10.56789
## Ylag1 -132.572387  263.8028379 -131.630812   -0.1890607  -47.24619   51.48936
## Ylag2   -5.687403 -131.6308118  275.959135 -115.0799501  -11.83466  -44.37429
## Ylag3  -23.793968   -0.1890607 -115.079950  276.7779608 -124.86094    8.02800
## Ylag4   42.614369  -47.2461935  -11.834662 -124.8609409  283.35528 -133.93526
## Ylag5  -10.567893   51.4893628  -44.374289    8.0280004 -133.93526  279.81194
## Ylag6  -12.658323   35.8853277    8.730404  -83.0326424   28.24849 -162.42744
## Ylag7   50.229407  -83.2969506   65.005963   39.5962850  -85.94309   45.72924
## Ylag8  -59.956366   44.3801893  -41.373572   22.7426254   50.14667  -33.11543
##             Ylag6      Ylag7      Ylag8
## Y      -12.658323   50.22941  -59.95637
## Ylag1   35.885328  -83.29695   44.38019
## Ylag2    8.730404   65.00596  -41.37357
## Ylag3  -83.032642   39.59628   22.74263
## Ylag4   28.248488  -85.94309   50.14667
## Ylag5 -162.427444   45.72924  -33.11543
## Ylag6  434.454488 -291.09083   41.55400
## Ylag7 -291.090828  548.55591 -288.54097
## Ylag8   41.553997 -288.54097  265.38374
## 
## $`K=0.001`
##                 Y       Ylag1       Ylag2        Ylag3      Ylag4        Ylag5
## Y      142.940182 -118.920190  -10.615023  -21.0147515   38.11269   -8.3826649
## Ylag1 -118.920190  238.461276 -114.931540   -4.1811650  -41.76804   45.1808722
## Ylag2  -10.615023 -114.931540  251.646936 -102.1541485  -14.35678  -38.5621273
## Ylag3  -21.014751   -4.181165 -102.154149  252.4127942 -108.90328   -0.7104457
## Ylag4   38.112693  -41.768039  -14.356776 -108.9032819  256.03423 -115.0232433
## Ylag5   -8.382665   45.180872  -38.562127   -0.7104457 -115.02324  252.0480407
## Ylag6   -7.341689   26.773726    9.451792  -66.9629443   11.62776 -133.8623562
## Ylag7   36.969096  -61.905051   50.434043   28.1883799  -64.37177   24.3515549
## Ylag8  -50.587179   31.895839  -31.143569   23.5011403   39.17173  -24.4365292
##             Ylag6      Ylag7      Ylag8
## Y       -7.341689   36.96910  -50.58718
## Ylag1   26.773726  -61.90505   31.89584
## Ylag2    9.451792   50.43404  -31.14357
## Ylag3  -66.962944   28.18838   23.50114
## Ylag4   11.627761  -64.37177   39.17173
## Ylag5 -133.862356   24.35155  -24.43653
## Ylag6  367.876562 -223.41553   15.57168
## Ylag7 -223.415535  442.48755 -232.46398
## Ylag8   15.571677 -232.46398  229.66456
## 
## $`K=0.0014`
##                 Y       Ylag1       Ylag2      Ylag3        Ylag4       Ylag5
## Y      133.783823 -107.534403  -14.174618 -18.657351   33.9811318   -6.357872
## Ylag1 -107.534403  217.227167 -101.285806  -7.350485  -36.8299646   39.444942
## Ylag2  -14.174618 -101.285806  230.869881 -91.143731  -16.2728635  -33.626617
## Ylag3  -18.657351   -7.350485  -91.143731 231.630149  -95.9899003   -6.895324
## Ylag4   33.981132  -36.829965  -16.272863 -95.989900  233.2909975 -100.086947
## Ylag5   -6.357872   39.444942  -33.626617  -6.895324 -100.0869466  229.239398
## Ylag6   -3.885270   20.594257    9.224259 -55.022274    0.4910535 -112.457233
## Ylag7   27.468173  -46.609508   39.760292  20.425018  -49.4251703   10.154081
## Ylag8  -43.476861   22.936770  -23.533873  23.170163   31.3446848  -18.841638
##              Ylag6      Ylag7       Ylag8
## Y       -3.8852700   27.46817  -43.476861
## Ylag1   20.5942575  -46.60951   22.936770
## Ylag2    9.2242586   39.76029  -23.533873
## Ylag3  -55.0222741   20.42502   23.170163
## Ylag4    0.4910535  -49.42517   31.344685
## Ylag5 -112.4572329   10.15408  -18.841638
## Ylag6  317.7683660 -175.61675   -1.327864
## Ylag7 -175.6167500  365.70706 -191.564787
## Ylag8   -1.3278636 -191.56479  202.426090
## 
## $`K=0.002`
##                 Y     Ylag1      Ylag2     Ylag3      Ylag4      Ylag5
## Y     122.1546645 -93.59952 -17.750054 -15.81140  28.562255  -3.775369
## Ylag1 -93.5995220 191.12681 -85.024608 -10.83735 -30.527675  32.048949
## Ylag2 -17.7500539 -85.02461 204.848845 -77.52376 -18.204658 -27.636043
## Ylag3 -15.8114035 -10.83735 -77.523761 205.61750 -80.700551 -13.011945
## Ylag4  28.5622552 -30.52768 -18.204658 -80.70055 205.445442 -82.824958
## Ylag5  -3.7753685  32.04895 -27.636043 -13.01195 -82.824958 201.656881
## Ylag6  -0.7289237  14.53332   8.115863 -42.13540  -9.940124 -89.034780
## Ylag7  17.6534273 -30.85671  28.435721  12.83692 -34.520448  -3.128633
## Ylag8 -35.5795343  13.71580 -15.384345  21.72303  23.185662 -13.759422
##              Ylag6       Ylag7      Ylag8
## Y       -0.7289237   17.653427  -35.57953
## Ylag1   14.5333159  -30.856713   13.71580
## Ylag2    8.1158625   28.435721  -15.38434
## Ylag3  -42.1353962   12.836925   21.72303
## Ylag4   -9.9401238  -34.520448   23.18566
## Ylag5  -89.0347797   -3.128633  -13.75942
## Ylag6  262.4354338 -126.809714  -16.60253
## Ylag7 -126.8097136  284.814897 -148.09793
## Ylag8  -16.6025284 -148.097926  171.87969

A seguir estão os possíveis usos de algumas funções para calcular diferentes estatísticas relacionadas ao ridge. Para descrição detalhada dessas funções / comandos, consulte a documentação do pacote lmridge.

# ridge$rfit
# resid(ridge)
# fitted(ridge)
 infocr(ridge)
##               AIC      BIC
## K=0      47.85786 162.5046
## K=2e-04  47.51329 161.9143
## K=6e-04  46.93097 160.8966
## K=0.001  46.45383 160.0418
## K=0.0014 46.05379 159.3082
## K=0.002  45.56150 158.3793
# press(ridge)

Tanto o AIC quanto o BIC aumentam conforme SQE aumenta. Além disso, ambos critérios penalizam modelos com muitas variáveis sendo que valores menores de AIC e BIC são preferíveis.

Como modelos com mais variáveis tendem a produzir menor SQE mas usam mais parâmetros, a melhor escolha é balancear o ajuste com a quantidade de variáveis.

Note que o modelo com \(K=\lambda=0.002\) é o que esses critérios escolhem.

Para determinados valores de \(X\), como para as primeiras cinco linhas da matriz \(X\), os valores previstos para alguns \(\lambda=K=0,0.0002,0.0006,\ldots\) serão calculados por predict():

pred<-predict(ridge)

pred[1:5,]
##        K=0  K=2e-04  K=6e-04  K=0.001 K=0.0014  K=0.002
## 1 235.9740 236.0065 236.0562 236.0979 236.1379 236.1983
## 2 235.7156 235.7272 235.7440 235.7613 235.7827 235.8229
## 3 237.6823 237.7056 237.7389 237.7661 237.7932 237.8364
## 4 241.6963 241.7101 241.7260 241.7374 241.7496 241.7716
## 5 246.1518 246.1438 246.1212 246.0992 246.0819 246.0649

O efeito da multicolinearidade nas estimativas dos coeficientes pode ser identificada usando diferentes gráficos exibições como ridge, FIV e graus de liberdade, plotagem de RSS contra gl, PRESS vs \(K\) e plotagem de viés, variância e EQM contra \(K\) etc.

plot(ridge)

plot(ridge, type = "vif", abline = FALSE)

plot(ridge, type = "ridge", abline = TRUE)

bias.plot(ridge, abline = TRUE)

info.plot(ridge, abline = TRUE)

cv.plot(ridge, abline = TRUE)

isrm.plot(ridge)

As linhas verticais no traço de ridge e traço VIF sugerem o valor ideal do parâmetro de viés \(K\) selecionado em que GCV é mínimo. A linha horizontal no traçado do ridge é a linha de referência em y = 0 para coeficiente de ridge em relação ao eixo vertical.

O gráfico de compensação de viés-variância (Figura 3) pode ser usado para selecionar o k ideal usando bias.plot(). A linha vertical no gráfico de compensação de viés-variância mostra o valor do parâmetro de viés k e a linha horizontal mostra o EQM mínimo para o ridge.

O gráfico dos critérios de seleção de modelo AIC e BIC para escolher o \(K\) ideal (Figura 4), info.plot() pode ser usado; A função cv.plot() plota a validação cruzada CV e GCV contra o parâmetro de viés k para a seleção ótima de \(K\) (ver Figura 5), isto é, as medidas da escala m e ISRM (Figura 6) por Vinod (1976) também podem ser plotadas a partir da função isrm.plot() e podem ser usadas para julgar o valor ótimo de \(K\).

A função rplots.plot() plota o painel de três visualizações, a saber (i) traço gl, (ii) RSS vs \(K\) e (iii) PRESS vs \(K\) e pode ser usado para julgar o valor ideal de \(K\), consulte a Figura 7 a seguir:

rplots.plot(ridge)

###Considerações finais

Neste tutorial, utilizamos os dados de exemplo presente na clássica literatura de G.S. Maddala, 2001, Introdução à Econometria utilizando a representação mais simples no Excel e com algumas contribuições de análises adicionais presentes na documentação de utilização do pacote lmridge do R.

Notavelmente, a distância em relação ao poder de análise, velocidade e qualidade do R é abissal em relação ao Excel por inúmeros outras razões (como p. ex. o guardar de scripts do que está sendo feito em cada etapa em poucas linhas de instruções e comandos).

Esperamos que em breve o uso do Excel para compreender os conceitos iniciais dos modelos econométricos e suas aplicações (ainda que limitadas), seja visto como um start para aqueles que gostam de trabalhar com dados econômicos e que; melhor e mais pessoas utilizem o pacote completo lmridge no R para aperfeiçoar seu trabalho.


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  1. Muitos autores utilizam \(k\) ao invés de \(\lambda\) com o intuito de evitar confusão com autovalores.↩︎

  2. todos esses modelos são revistos em N. R. Draper e R. Craig Van Nostrand, “Ridge Regressions and James-Stein Estimation: Review and Comments”, Technometrics, Vol. 21, No. 4, novembro de 1979, pp 451-466. Os autores não aprovam e discutem defeitos em cada um deles.↩︎

  3. W.G. Brown e B. R. Beattie, “Improving Estimates of Economic Parameters by the Use of Ridge Regression with Production Function Applications.” American Journal of Agricultural Economics, vol. 57, 1975, pp. 21-32.↩︎

  4. (Gary Smith e Frank Campbell, “A Critique of Some Ridge Regression Methods” (com discussão), Journal of the American Statistical Association, Vol. 75, março de 1980, pp. 74)↩︎

  5. Uma matriz identidade é uma matriz quadrada com a sua diagonal principal =1 e e os demais elementos são todos zeros.↩︎