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Sparsifying priors, and variable selection

Peter Ralph

28 January 2018 – Advanced Biological Statistics

Overview

Problems with linear models

  1. “Too much” noise (i.e., non-Normal noise).

  2. Too many variables.

Problems with linear models

  1. “Too much” noise (i.e., non-Normal noise).
  2. Too many variables. (today)

Variable selection

Example data

from Efron, Hastie, Johnstone, & Tibshirani
from Efron, Hastie, Johnstone, & Tibshirani
## Loaded lars 1.2
diabetes                 package:lars                  R Documentation

Blood and other measurements in diabetics

Description:

     The ‘diabetes’ data frame has 442 rows and 3 columns. These are
     the data used in the Efron et al "Least Angle Regression" paper.

Format:

     This data frame contains the following columns:

     x a matrix with 10 columns

     y a numeric vector

     x2 a matrix with 64 columns

The dataset has

  • 442 diabetes patients
  • 10 main variables: age, gender, body mass index, average blood pressure (map), and six blood serum measurements (tc, ldl, hdl, tch, ltg, glu)
  • 45 interactions, e.g. age:ldl
  • 9 quadratic effects, e.g. age^2
  • measure of disease progression taken one year later: y

plot of chunk show_cors

##             age         sex        bmi        map         tc        ldl
## age  1.00000000  0.17373710  0.1850847  0.3354267 0.26006082  0.2192431
## sex  0.17373710  1.00000000  0.0881614  0.2410132 0.03527682  0.1426373
## bmi  0.18508467  0.08816140  1.0000000  0.3954153 0.24977742  0.2611699
## map  0.33542671  0.24101317  0.3954153  1.0000000 0.24246971  0.1855578
## tc   0.26006082  0.03527682  0.2497774  0.2424697 1.00000000  0.8966630
## ldl  0.21924314  0.14263726  0.2611699  0.1855578 0.89666296  1.0000000
## hdl -0.07518097 -0.37908963 -0.3668110 -0.1787612 0.05151936 -0.1964551
## tch  0.20384090  0.33211509  0.4138066  0.2576534 0.54220728  0.6598169
## ltg  0.27077678  0.14991756  0.4461586  0.3934781 0.51550076  0.3183534
## glu  0.30173101  0.20813322  0.3886800  0.3904294 0.32571675  0.2906004
## y    0.18788875  0.04306200  0.5864501  0.4414838 0.21202248  0.1740536
##             hdl        tch        ltg        glu          y
## age -0.07518097  0.2038409  0.2707768  0.3017310  0.1878888
## sex -0.37908963  0.3321151  0.1499176  0.2081332  0.0430620
## bmi -0.36681098  0.4138066  0.4461586  0.3886800  0.5864501
## map -0.17876121  0.2576534  0.3934781  0.3904294  0.4414838
## tc   0.05151936  0.5422073  0.5155008  0.3257168  0.2120225
## ldl -0.19645512  0.6598169  0.3183534  0.2906004  0.1740536
## hdl  1.00000000 -0.7384927 -0.3985770 -0.2736973 -0.3947893
## tch -0.73849273  1.0000000  0.6178574  0.4172121  0.4304529
## ltg -0.39857700  0.6178574  1.0000000  0.4646705  0.5658834
## glu -0.27369730  0.4172121  0.4646705  1.0000000  0.3824835
## y   -0.39478925  0.4304529  0.5658834  0.3824835  1.0000000

Crossvalidation plan

  1. Put aside 20% of the data for testing.

  2. Refit the model.

  3. Predict the test data; compute \[\begin{aligned} S = \sqrt{\frac{1}{M} \sum_{k=1}^M (\hat y_i - y_i)^2} \end{aligned}\]

To be more thorough, we’d:

  1. Repeat for the other four 20%s.

  2. Compare.

Crossvalidation

First let’s split the data into testing and training just once:

Ordinary linear regression

## 
## Call:
## lm(formula = y ~ ., data = training_d)
## 
## Residuals:
##      Min       1Q   Median       3Q      Max 
## -144.317  -32.470   -1.103   30.758  150.394 
## 
## Coefficients:
##               Estimate Std. Error t value Pr(>|t|)    
## (Intercept)   150.6877     2.9522  51.042  < 2e-16 ***
## age            84.9492    76.8683   1.105 0.270040    
## sex          -269.6337    74.6079  -3.614 0.000357 ***
## bmi           472.7822    95.1685   4.968 1.17e-06 ***
## map           360.8680    83.4249   4.326 2.11e-05 ***
## tc          -5344.1362 61836.3128  -0.086 0.931190    
## ldl          4723.0002 54348.5345   0.087 0.930811    
## hdl          1680.5383 23107.3258   0.073 0.942074    
## tch           -85.1837   310.2802  -0.275 0.783871    
## ltg          2350.5648 20327.5502   0.116 0.908024    
## glu            89.6525    82.3631   1.089 0.277296    
## `age^2`        66.3267    81.7182   0.812 0.417671    
## `bmi^2`       -15.8074    98.0763  -0.161 0.872070    
## `map^2`       -52.3897    81.9032  -0.640 0.522914    
## `tc^2`       4501.3147  7881.9786   0.571 0.568391    
## `ldl^2`      1315.3476  5909.8058   0.223 0.824030    
## `hdl^2`      1030.4184  1782.5832   0.578 0.563690    
## `tch^2`      1153.5056   714.6967   1.614 0.107642    
## `ltg^2`      1092.0803  1792.2811   0.609 0.542797    
## `glu^2`       128.3360   105.6485   1.215 0.225472    
## `age:sex`     148.1955    90.6594   1.635 0.103232    
## `age:bmi`       0.2615    91.8545   0.003 0.997731    
## `age:map`      20.5937    92.2566   0.223 0.823524    
## `age:tc`     -381.4352   724.3415  -0.527 0.598885    
## `age:ldl`     210.2182   572.3353   0.367 0.713670    
## `age:hdl`     200.9052   332.3158   0.605 0.545953    
## `age:tch`      61.3932   261.2022   0.235 0.814346    
## `age:ltg`     226.9634   253.9241   0.894 0.372173    
## `age:glu`     123.5654    97.0127   1.274 0.203810    
## `sex:bmi`     151.2508    90.5864   1.670 0.096083 .  
## `sex:map`      34.8983    92.5784   0.377 0.706485    
## `sex:tc`      710.4735   742.2003   0.957 0.339254    
## `sex:ldl`    -583.0899   593.5042  -0.982 0.326713    
## `sex:hdl`     -89.0422   339.1340  -0.263 0.793082    
## `sex:tch`     -61.9876   232.1990  -0.267 0.789694    
## `sex:ltg`    -210.1018   273.3948  -0.768 0.442833    
## `sex:glu`       2.2142    83.6948   0.026 0.978913    
## `bmi:map`     232.7827   105.2676   2.211 0.027809 *  
## `bmi:tc`     -449.8107   783.8370  -0.574 0.566518    
## `bmi:ldl`     449.7137   655.6107   0.686 0.493307    
## `bmi:hdl`     123.4574   381.2367   0.324 0.746302    
## `bmi:tch`    -132.9843   266.2289  -0.500 0.617806    
## `bmi:ltg`     132.1058   300.4831   0.440 0.660529    
## `bmi:glu`      88.7750   100.3718   0.884 0.377195    
## `map:tc`      164.8893   829.9828   0.199 0.842666    
## `map:ldl`     -35.3650   692.9898  -0.051 0.959335    
## `map:hdl`     -84.9267   384.1101  -0.221 0.825173    
## `map:tch`    -114.1544   239.7704  -0.476 0.634370    
## `map:ltg`       3.8403   326.8067   0.012 0.990633    
## `map:glu`    -244.4812   107.7053  -2.270 0.023963 *  
## `tc:ldl`    -4837.7578 13111.3994  -0.369 0.712422    
## `tc:hdl`    -2183.9679  4297.1963  -0.508 0.611686    
## `tc:tch`    -2109.4859  1982.6917  -1.064 0.288255    
## `tc:ltg`    -2127.4764 13625.9468  -0.156 0.876038    
## `tc:glu`      950.9385   944.0604   1.007 0.314655    
## `ldl:hdl`     750.6735  3596.1704   0.209 0.834799    
## `ldl:tch`     685.7207  1687.0469   0.406 0.684709    
## `ldl:ltg`    1301.0314 11332.1780   0.115 0.908678    
## `ldl:glu`    -997.1770   828.4152  -1.204 0.229702    
## `hdl:tch`    1423.4284  1141.8773   1.247 0.213583    
## `hdl:ltg`     579.6892  4796.1460   0.121 0.903883    
## `hdl:glu`    -207.1879   418.5042  -0.495 0.620935    
## `tch:ltg`     231.5833   710.8052   0.326 0.744812    
## `tch:glu`     195.2469   265.2168   0.736 0.462230    
## `ltg:glu`    -262.9689   369.0101  -0.713 0.476658    
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## Residual standard error: 53.11 on 284 degrees of freedom
## Multiple R-squared:  0.6273, Adjusted R-squared:  0.5433 
## F-statistic: 7.469 on 64 and 284 DF,  p-value: < 2.2e-16

With ordinary linear regression, we got a root-mean-square-prediction-error of 61.3508494 (on the test data), compared to a root-mean-square-error of 47.9132317 for the training data.

This suggests there’s some overfitting going on.

plot of chunk plot_ols

A sparsifying prior

We have a lot of predictors: 64 of them. A good guess is that only a few are really useful. So, we can put a sparsifying prior on the coefficients, i.e., \(\beta\)s in \[\begin{aligned} y = \beta_0 + \beta_1 x_1 + \cdots \beta_n x_n + \epsilon \end{aligned}\]

Interlude

Estimation of infiltration rate from soil properties using regression model for cultivated land
Estimation of infiltration rate from soil properties using regression model for cultivated land
EIR = 14,195.35 - 141.75 (sand%) - 142.10 (silt%) - 142.56 (clay%)
EIR = 14,195.35 - 141.75 (sand%) - 142.10 (silt%) - 142.56 (clay%)

Use the data to try to reproduce their model:

BIR = 14,195.35 - 141.75 (sand%) - 142.10 (silt%) - 142.56 (clay%)

They’re not wrong! What’s going on?

Sparseness and scale mixtures

Encouraging sparseness

Suppose we do regression with a large number of predictor variables.

The resulting coefficients are sparse if most are zero.

The idea is to “encourage” all the coefficients to be zero, unless they really want to be nonzero, in which case we let them be whatever they want.

This tends to discourage overfitting.

The idea is to “encourage” all the coefficients to be zero, unless they really want to be nonzero, in which case we let them be whatever they want.

To do this, we want a prior which is very peak-ey at zero but flat away from zero (“spike-and-slab”).

Compare the Normal

\[\begin{aligned} X \sim \Normal(0,1) \end{aligned}\]

to the “exponential scale mixture of Normals”,

\[\begin{aligned} X &\sim \Normal(0,\sigma) \\ \sigma &\sim \Exp(1) . \end{aligned}\]

plot of chunk scale_mixturesplot of chunk scale_mixtures

Why use a scale mixture?

  1. Lets the data choose the appropriate scale of variation.

  2. Weakly encourages \(\sigma\) to be small: so, as much variation as possible is explained by signal instead of noise.

  3. Gets you a prior that is more peaked at zero and flatter otherwise.

Implementation

Note that

\[\begin{aligned} \beta &\sim \Normal(0,\sigma) \\ \sigma &\sim \Exp(1) . \end{aligned}\]

is equivalent to

\[\begin{aligned} \beta &= \sigma \gamma \\ \gamma &\sim \Normal(0,1) \\ \sigma &\sim \Exp(1) . \end{aligned}\]

parameters {
    real beta;
    real<lower=0> sigma;
}
model {
    beta ~ normal(0, sigma);
    sigma ~ exponential(1);
}

is equivalent to

parameters {
    real gamma;
    real<lower=0> sigma;
}
transformed parameters {
    real beta;
    beta = gamma * sigma;
}
model {
    gamma ~ normal(0, 1);
    sigma ~ exponential(1);
}

The second version is better for Stan.

Why is it better?

parameters {
    real beta;
    real<lower=0> sigma;
}
model {
    beta ~ normal(0, sigma);
}

In the first, the optimal step size depends on sigma.

plot of chunk sigma_phaseplot of chunk sigma_phase

A strongly sparsifying prior

The “horseshoe”:

\[\begin{aligned} \beta_j &\sim \Normal(0, \lambda_j) \\ \lambda_j &\sim \Cauchy(0, \tau) \\ \tau &\sim \Unif(0, 1) \end{aligned}\]

parameters {
    vector[p] d_beta;
    vector[p] d_lambda;
    real<lower=0, upper=1> tau;
}
transformed parameters {
    vector[p] beta;
    beta = d_beta .* d_lambda * tau;
}
model {
    d_beta ~ normal(0, 1);
    d_lambda ~ cauchy(0, 1);
    // tau ~ uniform(0, 1); // uniform
}

The Cauchy as a scale mixture

Recall that if

\[\begin{aligned} \beta &\sim \Normal(0, 1/\sqrt{\lambda}) \\ \lambda &\sim \Gam(1/2, 1/2) \end{aligned}\]

then

\[\begin{aligned} \beta &\sim \Cauchy(0, 1). \end{aligned}\]

Using the horseshoe

What’s an appropriate noise distribution?

plot of chunk show_y

Aside: quantile-quantile plots

The idea is to plot the quantiles of each distribution against each other.

If these are datasets, this means just plotting their sorted values against each other.

plot of chunk qq

Regression with a horseshoe prior

Uses a reparameterization of the Cauchy as a scale mixture of normals.

Note the data have already been normalized, with the exception of \(y\):

##        y              age                 sex            
##  Min.   : 25.0   Min.   :-0.107226   Min.   :-0.0446416  
##  1st Qu.: 84.0   1st Qu.:-0.038207   1st Qu.:-0.0446416  
##  Median :141.0   Median : 0.005383   Median :-0.0446416  
##  Mean   :151.9   Mean   :-0.001133   Mean   : 0.0001514  
##  3rd Qu.:214.0   3rd Qu.: 0.034443   3rd Qu.: 0.0506801  
##  Max.   :341.0   Max.   : 0.110727   Max.   : 0.0506801  
##       bmi                  map                   tc            
##  Min.   :-0.0891975   Min.   :-0.1089567   Min.   :-1.089e-01  
##  1st Qu.:-0.0342291   1st Qu.:-0.0332136   1st Qu.:-3.322e-02  
##  Median :-0.0072838   Median :-0.0056706   Median :-4.321e-03  
##  Mean   : 0.0007334   Mean   :-0.0009289   Mean   : 4.355e-05  
##  3rd Qu.: 0.0336731   3rd Qu.: 0.0322010   3rd Qu.: 2.733e-02  
##  Max.   : 0.1705552   Max.   : 0.1320442   Max.   : 1.539e-01  
##       ldl                  hdl                 tch           
##  Min.   :-0.1156131   Min.   :-0.102307   Min.   :-0.076395  
##  1st Qu.:-0.0294972   1st Qu.:-0.036038   1st Qu.:-0.039493  
##  Median :-0.0038191   Median :-0.006584   Median :-0.002592  
##  Mean   : 0.0006148   Mean   :-0.001146   Mean   : 0.001683  
##  3rd Qu.: 0.0312536   3rd Qu.: 0.026550   3rd Qu.: 0.034309  
##  Max.   : 0.1987880   Max.   : 0.181179   Max.   : 0.185234  
##       ltg                  glu                age^2           
##  Min.   :-0.1260974   Min.   :-0.137767   Min.   :-0.0413003  
##  1st Qu.:-0.0345237   1st Qu.:-0.034215   1st Qu.:-0.0365111  
##  Median :-0.0042199   Median : 0.003064   Median :-0.0196705  
##  Mean   :-0.0003819   Mean   : 0.001320   Mean   :-0.0009618  
##  3rd Qu.: 0.0336568   3rd Qu.: 0.032059   3rd Qu.: 0.0167284  
##  Max.   : 0.1335990   Max.   : 0.135612   Max.   : 0.1827574  
##      bmi^2               map^2                tc^2           
##  Min.   :-0.032976   Min.   :-0.039369   Min.   :-0.0319463  
##  1st Qu.:-0.029289   1st Qu.:-0.034915   1st Qu.:-0.0293480  
##  Median :-0.015899   Median :-0.020173   Median :-0.0176317  
##  Mean   : 0.001105   Mean   :-0.001515   Mean   :-0.0007156  
##  3rd Qu.: 0.015956   3rd Qu.: 0.017791   3rd Qu.: 0.0049295  
##  Max.   : 0.391017   Max.   : 0.264034   Max.   : 0.3025598  
##      ldl^2                hdl^2                tch^2          
##  Min.   :-0.0296059   Min.   :-0.0276538   Min.   :-0.030537  
##  1st Qu.:-0.0263734   1st Qu.:-0.0247218   1st Qu.:-0.029197  
##  Median :-0.0177320   Median :-0.0135994   Median :-0.009485  
##  Mean   : 0.0002449   Mean   :-0.0001651   Mean   : 0.002614  
##  3rd Qu.: 0.0069595   3rd Qu.: 0.0085816   3rd Qu.:-0.009485  
##  Max.   : 0.4875149   Max.   : 0.3736758   Max.   : 0.432612  
##      ltg^2                glu^2               age:sex          
##  Min.   :-0.0349354   Min.   :-0.0319022   Min.   :-0.1206953  
##  1st Qu.:-0.0298674   1st Qu.:-0.0293459   1st Qu.:-0.0308881  
##  Median :-0.0174442   Median :-0.0174185   Median : 0.0013654  
##  Mean   : 0.0008941   Mean   : 0.0007775   Mean   : 0.0004204  
##  3rd Qu.: 0.0166527   3rd Qu.: 0.0106420   3rd Qu.: 0.0350096  
##  Max.   : 0.2406822   Max.   : 0.2358489   Max.   : 0.1116139  
##     age:bmi              age:map               age:tc         
##  Min.   :-0.1473126   Min.   :-1.664e-01   Min.   :-0.136218  
##  1st Qu.:-0.0218929   1st Qu.:-2.038e-02   1st Qu.:-0.021240  
##  Median :-0.0066103   Median :-8.808e-03   Median :-0.009841  
##  Mean   : 0.0002062   Mean   : 9.330e-06   Mean   :-0.002694  
##  3rd Qu.: 0.0194927   3rd Qu.: 2.064e-02   3rd Qu.: 0.015148  
##  Max.   : 0.1702584   Max.   : 2.276e-01   Max.   : 0.184848  
##     age:ldl             age:hdl             age:tch          
##  Min.   :-0.155477   Min.   :-0.180044   Min.   :-0.2012887  
##  1st Qu.:-0.021123   1st Qu.:-0.024535   1st Qu.:-0.0176798  
##  Median :-0.008090   Median : 0.001289   Median :-0.0085659  
##  Mean   :-0.001742   Mean   :-0.002890   Mean   : 0.0003425  
##  3rd Qu.: 0.014305   3rd Qu.: 0.016814   3rd Qu.: 0.0210437  
##  Max.   : 0.206119   Max.   : 0.179882   Max.   : 0.2841256  
##     age:ltg              age:glu            sex:bmi          
##  Min.   :-0.1600509   Min.   :-0.11978   Min.   :-0.1259500  
##  1st Qu.:-0.0224627   1st Qu.:-0.02097   1st Qu.:-0.0363986  
##  Median :-0.0084704   Median :-0.01028   Median :-0.0016333  
##  Mean   :-0.0001848   Mean   : 0.00226   Mean   : 0.0002993  
##  3rd Qu.: 0.0201877   3rd Qu.: 0.01687   3rd Qu.: 0.0343105  
##  Max.   : 0.1870968   Max.   : 0.18437   Max.   : 0.1791461  
##     sex:map              sex:tc            sex:ldl          
##  Min.   :-0.140436   Min.   :-0.12103   Min.   :-0.1296905  
##  1st Qu.:-0.033378   1st Qu.:-0.03234   1st Qu.:-0.0320472  
##  Median : 0.000867   Median :-0.00149   Median :-0.0005132  
##  Mean   :-0.001420   Mean   :-0.00164   Mean   :-0.0008842  
##  3rd Qu.: 0.035112   3rd Qu.: 0.03065   3rd Qu.: 0.0286961  
##  Max.   : 0.103602   Max.   : 0.16157   Max.   : 0.2061352  
##     sex:hdl             sex:tch             sex:ltg         
##  Min.   :-0.165982   Min.   :-0.159990   Min.   :-0.142948  
##  1st Qu.:-0.033930   1st Qu.:-0.019548   1st Qu.:-0.034382  
##  Median :-0.003747   Median : 0.007811   Median : 0.004080  
##  Mean   :-0.001073   Mean   : 0.000675   Mean   :-0.001447  
##  3rd Qu.: 0.030209   3rd Qu.: 0.022402   3rd Qu.: 0.031844  
##  Max.   : 0.161942   Max.   : 0.191242   Max.   : 0.136396  
##     sex:glu             bmi:map              bmi:tc          
##  Min.   :-0.140447   Min.   :-0.125357   Min.   :-0.2932071  
##  1st Qu.:-0.032982   1st Qu.:-0.021323   1st Qu.:-0.0193874  
##  Median :-0.005120   Median :-0.010593   Median :-0.0081623  
##  Mean   :-0.001826   Mean   : 0.001654   Mean   : 0.0004349  
##  3rd Qu.: 0.033874   3rd Qu.: 0.016837   3rd Qu.: 0.0196646  
##  Max.   : 0.133283   Max.   : 0.228483   Max.   : 0.2269828  
##     bmi:ldl              bmi:hdl              bmi:tch          
##  Min.   :-0.2865770   Min.   :-0.2683161   Min.   :-0.1318179  
##  1st Qu.:-0.0220924   1st Qu.:-0.0192972   1st Qu.:-0.0240342  
##  Median :-0.0081638   Median : 0.0114850   Median :-0.0162773  
##  Mean   : 0.0005709   Mean   :-0.0001998   Mean   : 0.0005282  
##  3rd Qu.: 0.0160003   3rd Qu.: 0.0257027   3rd Qu.: 0.0212457  
##  Max.   : 0.2320688   Max.   : 0.1464774   Max.   : 0.2764597  
##     bmi:ltg              bmi:glu               map:tc         
##  Min.   :-0.1850927   Min.   :-0.1543918   Min.   :-0.202259  
##  1st Qu.:-0.0242869   1st Qu.:-0.0243900   1st Qu.:-0.020118  
##  Median :-0.0120359   Median :-0.0145264   Median :-0.009291  
##  Mean   : 0.0004121   Mean   : 0.0002221   Mean   :-0.001904  
##  3rd Qu.: 0.0224404   3rd Qu.: 0.0187559   3rd Qu.: 0.017553  
##  Max.   : 0.2188921   Max.   : 0.2246097   Max.   : 0.189747  
##     map:ldl             map:hdl              map:tch          
##  Min.   :-0.203862   Min.   :-0.2827677   Min.   :-0.1448773  
##  1st Qu.:-0.020139   1st Qu.:-0.0195326   1st Qu.:-0.0176903  
##  Median :-0.007217   Median : 0.0052223   Median :-0.0103528  
##  Mean   :-0.001439   Mean   :-0.0009419   Mean   :-0.0003524  
##  3rd Qu.: 0.017901   3rd Qu.: 0.0195291   3rd Qu.: 0.0210655  
##  Max.   : 0.191608   Max.   : 0.1411591   Max.   : 0.2294877  
##     map:ltg              map:glu              tc:ldl          
##  Min.   :-0.1458925   Min.   :-0.143393   Min.   :-0.0417981  
##  1st Qu.:-0.0241548   1st Qu.:-0.023305   1st Qu.:-0.0271710  
##  Median :-0.0115420   Median :-0.012891   Median :-0.0167630  
##  Mean   :-0.0007273   Mean   :-0.001198   Mean   :-0.0000399  
##  3rd Qu.: 0.0243220   3rd Qu.: 0.010728   3rd Qu.: 0.0061787  
##  Max.   : 0.1871399   Max.   : 0.222465   Max.   : 0.3976457  
##      tc:hdl              tc:tch              tc:ltg          
##  Min.   :-0.210843   Min.   :-0.122355   Min.   :-0.1048969  
##  1st Qu.:-0.020049   1st Qu.:-0.022213   1st Qu.:-0.0258507  
##  Median :-0.003359   Median :-0.015596   Median :-0.0147751  
##  Mean   :-0.002995   Mean   : 0.001508   Mean   : 0.0003344  
##  3rd Qu.: 0.011968   3rd Qu.: 0.011853   3rd Qu.: 0.0169747  
##  Max.   : 0.318951   Max.   : 0.469153   Max.   : 0.2231252  
##      tc:glu             ldl:hdl             ldl:tch         
##  Min.   :-0.120530   Min.   :-0.256471   Min.   :-0.111508  
##  1st Qu.:-0.020704   1st Qu.:-0.017056   1st Qu.:-0.023581  
##  Median :-0.010736   Median : 0.004701   Median :-0.014035  
##  Mean   : 0.001909   Mean   :-0.002493   Mean   : 0.001698  
##  3rd Qu.: 0.014115   3rd Qu.: 0.017148   3rd Qu.: 0.011949  
##  Max.   : 0.237370   Max.   : 0.160773   Max.   : 0.555129  
##     ldl:ltg             ldl:glu             hdl:tch         
##  Min.   :-0.182594   Min.   :-0.122560   Min.   :-0.234890  
##  1st Qu.:-0.020687   1st Qu.:-0.020314   1st Qu.:-0.019367  
##  Median :-0.007486   Median :-0.009531   Median : 0.014418  
##  Mean   : 0.001251   Mean   : 0.001666   Mean   :-0.002127  
##  3rd Qu.: 0.024513   3rd Qu.: 0.015106   3rd Qu.: 0.030898  
##  Max.   : 0.203381   Max.   : 0.299032   Max.   : 0.060843  
##     hdl:ltg             hdl:glu             tch:ltg         
##  Min.   :-0.254685   Min.   :-0.223255   Min.   :-0.160745  
##  1st Qu.:-0.018987   1st Qu.:-0.014712   1st Qu.:-0.026638  
##  Median : 0.007072   Median : 0.009179   Median :-0.011590  
##  Mean   :-0.002375   Mean   : 0.001057   Mean   : 0.002223  
##  3rd Qu.: 0.021259   3rd Qu.: 0.023064   3rd Qu.: 0.017732  
##  Max.   : 0.163067   Max.   : 0.209905   Max.   : 0.375845  
##     tch:glu              ltg:glu          
##  Min.   :-0.1289188   Min.   :-0.0921654  
##  1st Qu.:-0.0209368   1st Qu.:-0.0234429  
##  Median :-0.0155472   Median :-0.0127174  
##  Mean   : 0.0003502   Mean   : 0.0002222  
##  3rd Qu.: 0.0208725   3rd Qu.: 0.0140169  
##  Max.   : 0.3181041   Max.   : 0.1953000
## Warning: There were 10 divergent transitions after warmup. Increasing adapt_delta above 0.999 may help. See
## http://mc-stan.org/misc/warnings.html#divergent-transitions-after-warmup
## Warning: Examine the pairs() plot to diagnose sampling problems
## $summary
##                   mean      se_mean         sd        2.5%          25%
## b0        0.1171386679 0.0004781465 0.03268656  0.05123352  0.095954334
## sigma     0.5939505706 0.0004895491 0.02510540  0.54754339  0.575928625
## beta[1]   0.2067720870 0.0116973375 0.45500667 -0.43095590 -0.032993312
## beta[2]  -1.3267070644 0.0308211425 1.01191219 -3.31036790 -2.089888447
## beta[3]   5.9469514755 0.0239646656 0.94286301  4.08058479  5.321273444
## beta[4]   3.4058534548 0.0271413270 0.96979626  1.39867143  2.806153360
## beta[5]  -0.2195246520 0.0192556278 0.63705136 -2.02446851 -0.298823254
## beta[6]  -0.0005838563 0.0146438565 0.49601186 -0.95172400 -0.157314779
## beta[7]  -1.4217090432 0.0403492258 1.27040913 -4.09534885 -2.370132340
## beta[8]   0.2912977580 0.0229274336 0.79077567 -0.82881493 -0.058932017
## beta[9]   5.6916311352 0.0228957643 0.95970360  3.71162190  5.079233774
## beta[10]  0.2839667992 0.0126317887 0.51306992 -0.38549293 -0.011734618
## beta[11]  0.2239066703 0.0122525145 0.46776754 -0.42295417 -0.030382625
## beta[12]  0.1408198497 0.0126733816 0.45630207 -0.66402209 -0.048620150
## beta[13]  0.0390482818 0.0106256284 0.38020217 -0.80319411 -0.092919631
## beta[14] -0.0673891285 0.0155806106 0.49909484 -1.21539377 -0.193572703
## beta[15] -0.0743043028 0.0130341601 0.46316098 -1.17004832 -0.192681374
## beta[16]  0.0444917219 0.0125864525 0.43701819 -0.88801853 -0.100961027
## beta[17]  0.0549449770 0.0133163259 0.49358182 -0.91606532 -0.104742147
## beta[18] -0.2684959442 0.0134224162 0.52454512 -1.75910424 -0.417963524
## beta[19]  0.7440743795 0.0232191682 0.84893795 -0.24298590  0.041535252
## beta[20]  1.4988432145 0.0270918819 0.94033655 -0.04685249  0.763412650
## beta[21]  0.2184550080 0.0130569909 0.48154862 -0.44089418 -0.030705911
## beta[22]  0.2915542247 0.0129977529 0.52060886 -0.39570366 -0.010667235
## beta[23] -0.0041695605 0.0122879353 0.48031163 -1.04273030 -0.139768654
## beta[24] -0.1410223534 0.0135062895 0.50480443 -1.43150933 -0.249069445
## beta[25]  0.0352698171 0.0102745834 0.37780923 -0.71924328 -0.101232493
## beta[26]  0.0550076269 0.0120620113 0.43427943 -0.78664136 -0.096375309
## beta[27]  0.3347528799 0.0155304380 0.59571132 -0.43329814 -0.007684928
## beta[28]  0.2992498630 0.0146263667 0.55536789 -0.40932136 -0.015935502
## beta[29]  0.5194072205 0.0163355642 0.66172946 -0.25043241  0.014438776
## beta[30]  0.1612223956 0.0123912082 0.43503119 -0.48405230 -0.042471904
## beta[31]  0.0879988942 0.0113313049 0.44248044 -0.67323338 -0.076145621
## beta[32] -0.1227032184 0.0127238228 0.44356419 -1.24075877 -0.245610924
## beta[33]  0.3875082091 0.0168286572 0.63660852 -0.36044824 -0.001413730
## beta[34] -0.1551703861 0.0117478716 0.48468544 -1.46916868 -0.265495769
## beta[35]  0.0580899192 0.0114590655 0.39051887 -0.67422679 -0.093446760
## beta[36]  0.0061457359 0.0093049230 0.34289701 -0.73081003 -0.113548186
## beta[37]  0.8393014351 0.0235712372 0.87656251 -0.21391343  0.084195847
## beta[38] -0.0067733462 0.0117104253 0.40537738 -0.97576731 -0.130374321
## beta[39]  0.0291835117 0.0126277473 0.41103391 -0.78899058 -0.108616944
## beta[40] -0.0362189763 0.0112156048 0.39343131 -0.99160185 -0.155681301
## beta[41]  0.0395752320 0.0120113744 0.41125254 -0.83778583 -0.109785377
## beta[42]  0.0265325481 0.0103610931 0.36102124 -0.78008829 -0.092488052
## beta[43]  0.3173534369 0.0170864534 0.58976646 -0.37800536 -0.019909938
## beta[44]  0.1212078105 0.0107852776 0.42661479 -0.52290468 -0.061163915
## beta[45]  0.0687655053 0.0113090741 0.39192909 -0.68984913 -0.073972882
## beta[46]  0.1609415140 0.0115134285 0.44061652 -0.57777384 -0.036343880
## beta[47] -0.1269082628 0.0113697868 0.43058220 -1.28907430 -0.239303063
## beta[48]  0.0427466073 0.0113489200 0.39975453 -0.81425903 -0.091415154
## beta[49] -0.1843254871 0.0161911072 0.50507323 -1.69701472 -0.295827324
## beta[50] -0.0149311764 0.0137449892 0.47079056 -1.02541218 -0.152907786
## beta[51]  0.0855073292 0.0118470130 0.45521366 -0.72472117 -0.078010116
## beta[52] -0.3918323523 0.0221778625 0.82406625 -2.66278049 -0.517832963
## beta[53] -0.1170604064 0.0128936987 0.47770884 -1.38203954 -0.222942283
## beta[54]  0.0586391947 0.0121317551 0.43439120 -0.82568780 -0.091002900
## beta[55] -0.0811017433 0.0121072823 0.44655911 -1.25504976 -0.177711031
## beta[56] -0.0281827085 0.0142767043 0.51639048 -1.21032070 -0.178067186
## beta[57]  0.2540292719 0.0164884812 0.59825389 -0.56211277 -0.037751602
## beta[58]  0.0350466741 0.0126992590 0.40695819 -0.78107453 -0.110777325
## beta[59] -0.1647790867 0.0154203899 0.51993278 -1.54200922 -0.290014668
## beta[60]  0.0928386210 0.0124650314 0.43140247 -0.66812170 -0.079143578
## beta[61]  0.0514490181 0.0108544923 0.40491733 -0.71203294 -0.100112430
## beta[62] -0.1514022120 0.0137719081 0.49740021 -1.48318071 -0.270146256
## beta[63]  0.1330557437 0.0126310080 0.47118959 -0.68400098 -0.063335686
## beta[64]  0.1725288709 0.0146560075 0.50016905 -0.56829006 -0.053460297
##                    50%         75%     97.5%     n_eff      Rhat
## b0        0.1174633780  0.13781756 0.1808598 4673.2223 0.9981943
## sigma     0.5930541177  0.61117174 0.6436862 2629.9148 0.9987985
## beta[1]   0.0583527175  0.33987376 1.4739125 1513.0786 1.0008314
## beta[2]  -1.2828790932 -0.41150590 0.1034230 1077.9241 1.0012010
## beta[3]   5.9544680853  6.56571502 7.7604595 1547.9412 1.0004329
## beta[4]   3.4409193977  4.07777118 5.1797714 1276.7294 1.0014067
## beta[5]  -0.0457712145  0.04849509 0.5723654 1094.5448 1.0002889
## beta[6]  -0.0004106395  0.13171404 1.0338783 1147.2900 1.0040715
## beta[7]  -1.2512015232 -0.21611167 0.1810439  991.3267 1.0023848
## beta[8]   0.0558930462  0.41495668 2.5989737 1189.5856 1.0008905
## beta[9]   5.6915589934  6.34557242 7.4872792 1756.9684 0.9996373
## beta[10]  0.1092051779  0.46726719 1.6495121 1649.7700 0.9984770
## beta[11]  0.0725696047  0.38677401 1.4809376 1457.5038 0.9994269
## beta[12]  0.0274844589  0.24952640 1.4085508 1296.3428 0.9995646
## beta[13]  0.0130628300  0.16520307 0.9326926 1280.3242 1.0003070
## beta[14] -0.0108535116  0.09568344 0.8033613 1026.1178 1.0013503
## beta[15] -0.0161101211  0.08077664 0.8399055 1262.6932 0.9998143
## beta[16]  0.0092266119  0.16220637 1.0713291 1205.5698 1.0021387
## beta[17]  0.0040313052  0.16695667 1.3020137 1373.8822 1.0005258
## beta[18] -0.0846294775  0.02245941 0.3639800 1527.2295 1.0014334
## beta[19]  0.4765655755  1.28989698 2.7428290 1336.7758 1.0024413
## beta[20]  1.5429237040  2.18120745 3.2236885 1204.7260 1.0003347
## beta[21]  0.0627110254  0.38852775 1.5523038 1360.1728 1.0021517
## beta[22]  0.1064555246  0.47065111 1.6994627 1604.3036 1.0025897
## beta[23] -0.0019479333  0.11661139 1.0085449 1527.8769 1.0032812
## beta[24] -0.0278686346  0.06359624 0.5781162 1396.9286 1.0035052
## beta[25]  0.0064990426  0.15699202 0.9038176 1352.1245 1.0004284
## beta[26]  0.0089800845  0.17404053 1.1109759 1296.2807 0.9996915
## beta[27]  0.1185590780  0.54104941 2.0132696 1471.3104 1.0010922
## beta[28]  0.1063858059  0.50734148 1.7682516 1441.7455 1.0015606
## beta[29]  0.2860054887  0.87638353 2.1176654 1640.9399 0.9999925
## beta[30]  0.0378664746  0.27569830 1.3909351 1232.5753 1.0015505
## beta[31]  0.0168137944  0.19710559 1.1085428 1524.8541 1.0000316
## beta[32] -0.0333525880  0.05642478 0.5911748 1215.2838 1.0028163
## beta[33]  0.1436673696  0.60733150 2.1410353 1431.0209 0.9985586
## beta[34] -0.0416249280  0.04938128 0.6179006 1702.1646 1.0003856
## beta[35]  0.0105197741  0.17930276 1.0225941 1161.4102 1.0020227
## beta[36] -0.0002245339  0.11180802 0.8107868 1358.0065 0.9997001
## beta[37]  0.6156491878  1.38687684 2.8762906 1382.9326 1.0011229
## beta[38]  0.0019643105  0.12956612 0.8398895 1198.3224 0.9998495
## beta[39]  0.0042697884  0.15895878 1.0188405 1059.5063 0.9991121
## beta[40] -0.0052469627  0.11985874 0.6963084 1230.5307 1.0022412
## beta[41]  0.0056298431  0.17165634 1.0433936 1172.2811 0.9989847
## beta[42]  0.0090162747  0.14879940 0.8744792 1214.0997 1.0009150
## beta[43]  0.1048639201  0.50973973 1.9416476 1191.3964 1.0005611
## beta[44]  0.0221466020  0.22347520 1.2542605 1564.6210 1.0012062
## beta[45]  0.0144928031  0.18402312 0.9963205 1201.0495 1.0032669
## beta[46]  0.0470453257  0.27976144 1.3133182 1464.5770 1.0018140
## beta[47] -0.0288901833  0.05034511 0.5585635 1434.1927 0.9999906
## beta[48]  0.0059956443  0.16306798 1.0438491 1240.7313 1.0045796
## beta[49] -0.0417027809  0.04734276 0.5095879  973.0958 1.0058077
## beta[50] -0.0050903209  0.11216976 1.0384733 1173.1855 1.0004226
## beta[51]  0.0175645083  0.20007810 1.1728645 1476.4299 0.9988689
## beta[52] -0.0963741978  0.02394005 0.5040144 1380.6541 0.9996173
## beta[53] -0.0239994834  0.07732414 0.6398979 1372.6870 1.0007044
## beta[54]  0.0116726396  0.18632172 1.0973609 1282.0790 1.0014237
## beta[55] -0.0150495709  0.08134117 0.6828430 1360.3936 1.0013230
## beta[56] -0.0091164060  0.11294121 1.0792873 1308.2795 1.0009403
## beta[57]  0.0630178237  0.38769091 2.0075926 1316.4663 0.9997943
## beta[58]  0.0042205694  0.14978491 0.9799270 1026.9347 1.0027372
## beta[59] -0.0323090092  0.06191273 0.6600763 1136.8514 1.0012400
## beta[60]  0.0146268575  0.20927384 1.2056526 1197.7840 1.0023166
## beta[61]  0.0118951797  0.17347609 1.0403938 1391.5977 0.9995883
## beta[62] -0.0283632948  0.06229181 0.6616868 1304.4388 0.9995702
## beta[63]  0.0275670646  0.25021383 1.2977763 1391.6030 1.0060722
## beta[64]  0.0309454843  0.28404940 1.4884209 1164.6683 1.0020854
## 
## $c_summary
## , , chains = chain:1
## 
##           stats
## parameter          mean         sd        2.5%          25%           50%
##   b0        0.116819591 0.03260293  0.05452339  0.094853183  1.171957e-01
##   sigma     0.594475216 0.02465153  0.54972330  0.577426347  5.937568e-01
##   beta[1]   0.192300326 0.49590429 -0.49950256 -0.053018405  4.746219e-02
##   beta[2]  -1.202346708 1.01944679 -3.20038904 -2.037633825 -1.125308e+00
##   beta[3]   6.034651404 0.92196628  4.28768476  5.391851855  6.034356e+00
##   beta[4]   3.301180670 1.00367958  1.01886274  2.753966389  3.347926e+00
##   beta[5]  -0.212634029 0.63954521 -2.26335097 -0.308201282 -2.912796e-02
##   beta[6]  -0.032592175 0.48335470 -1.02723839 -0.155346323 -7.064470e-03
##   beta[7]  -1.281542909 1.29734297 -4.18815711 -2.171811102 -9.748373e-01
##   beta[8]   0.316772315 0.84459958 -0.80508305 -0.064825493  5.511235e-02
##   beta[9]   5.702639240 0.96108448  3.73206404  5.082532550  5.737076e+00
##   beta[10]  0.263922659 0.48596602 -0.45735061 -0.006287027  1.228802e-01
##   beta[11]  0.234782619 0.49597748 -0.49517009 -0.038140056  6.298256e-02
##   beta[12]  0.148106963 0.46317989 -0.66406719 -0.043714944  2.358228e-02
##   beta[13]  0.045429709 0.34151128 -0.71761207 -0.080194910  1.889652e-02
##   beta[14] -0.099946700 0.54083966 -1.36975654 -0.234132650 -1.225931e-02
##   beta[15] -0.096076825 0.50469988 -1.30572623 -0.215568255 -2.572397e-02
##   beta[16]  0.060906785 0.45291994 -0.84094301 -0.076778848  1.712506e-02
##   beta[17]  0.088714068 0.49593193 -0.75402125 -0.098786880  3.824426e-03
##   beta[18] -0.283723250 0.53921489 -1.77290567 -0.451019163 -7.495942e-02
##   beta[19]  0.824793548 0.89269590 -0.18062124  0.056482346  5.218833e-01
##   beta[20]  1.516465371 0.93431147 -0.01730351  0.792688985  1.508457e+00
##   beta[21]  0.233349795 0.51241061 -0.46561726 -0.023596053  4.698829e-02
##   beta[22]  0.279048797 0.49204422 -0.38240615 -0.008553342  1.077269e-01
##   beta[23]  0.001632467 0.50269504 -1.13408468 -0.126121886  2.109839e-03
##   beta[24] -0.164527183 0.48692117 -1.33239696 -0.324312620 -5.158198e-02
##   beta[25]  0.017944999 0.40776659 -0.92082618 -0.129553762  2.909115e-03
##   beta[26]  0.038759021 0.43047739 -0.77761237 -0.131942215  9.557057e-03
##   beta[27]  0.368824904 0.61327942 -0.48686084 -0.004907004  1.725301e-01
##   beta[28]  0.311889962 0.56034611 -0.38549194 -0.009039699  9.669412e-02
##   beta[29]  0.558173295 0.66578052 -0.22840462  0.037673571  3.528444e-01
##   beta[30]  0.166543487 0.44041193 -0.40221432 -0.038919036  2.836617e-02
##   beta[31]  0.060999784 0.41932589 -0.70847091 -0.092498273  6.765288e-03
##   beta[32] -0.126869908 0.40867208 -1.19129169 -0.260702635 -3.857450e-02
##   beta[33]  0.407790351 0.64230552 -0.35181535  0.008069043  1.600046e-01
##   beta[34] -0.138160112 0.47464096 -1.40628044 -0.251083987 -4.713581e-02
##   beta[35]  0.065928600 0.40754029 -0.69639030 -0.089504971  9.322716e-03
##   beta[36]  0.013581491 0.35360216 -0.64642415 -0.132299237  6.891629e-06
##   beta[37]  0.840588022 0.90129992 -0.20306218  0.065876775  6.125669e-01
##   beta[38] -0.018028013 0.38379719 -0.88036704 -0.143125332  1.350567e-03
##   beta[39]  0.035125813 0.45634281 -0.85521101 -0.072351493  1.210635e-02
##   beta[40] -0.013639827 0.35985219 -0.86568847 -0.117662374  4.549731e-03
##   beta[41]  0.057125015 0.42434857 -0.86910638 -0.092546674  1.671171e-02
##   beta[42]  0.007695474 0.35059543 -0.84605518 -0.088185733  6.387712e-03
##   beta[43]  0.321910068 0.54838220 -0.33973865 -0.016265314  1.175390e-01
##   beta[44]  0.133746534 0.43163236 -0.57801503 -0.053180816  4.057357e-02
##   beta[45]  0.069382791 0.38647793 -0.70323252 -0.072877632  1.469192e-02
##   beta[46]  0.166918993 0.41127587 -0.47479629 -0.027153254  5.770905e-02
##   beta[47] -0.141028562 0.42465049 -1.18576386 -0.288470050 -2.882831e-02
##   beta[48]  0.087272014 0.39959590 -0.63344413 -0.080778904  1.521632e-02
##   beta[49] -0.274523481 0.53143733 -1.74614935 -0.438629961 -1.069056e-01
##   beta[50]  0.023123967 0.48639248 -0.90593295 -0.119823883 -4.427334e-03
##   beta[51]  0.074065226 0.38697473 -0.57984738 -0.063775545  1.882819e-02
##   beta[52] -0.366908960 0.77522631 -2.54731466 -0.445454227 -1.019552e-01
##   beta[53] -0.107271774 0.44577454 -1.17969738 -0.218954663 -3.243512e-02
##   beta[54]  0.047581235 0.45583813 -0.79681374 -0.114053140  2.303990e-03
##   beta[55] -0.054977848 0.41662215 -1.13166696 -0.189376918 -5.832832e-03
##   beta[56] -0.072076473 0.49556561 -1.26583040 -0.245948401 -1.993747e-02
##   beta[57]  0.239532597 0.61798631 -0.57445762 -0.048942877  4.626406e-02
##   beta[58]  0.050735630 0.43313327 -0.79759280 -0.116309401  3.158778e-03
##   beta[59] -0.130081047 0.54106665 -1.60495078 -0.214157132 -1.079634e-02
##   beta[60]  0.107090007 0.46600979 -0.77498968 -0.080258030  2.575756e-02
##   beta[61]  0.048328295 0.38121913 -0.66414197 -0.099853696  1.291490e-02
##   beta[62] -0.153323337 0.51457405 -1.73541732 -0.280619916 -2.449540e-02
##   beta[63]  0.098612521 0.41716382 -0.65382184 -0.074201304  2.312085e-02
##   beta[64]  0.147297376 0.54983105 -0.76710362 -0.072247380  2.480682e-02
##           stats
## parameter           75%     97.5%
##   b0        0.138055670 0.1790165
##   sigma     0.611222774 0.6423486
##   beta[1]   0.276653642 1.6368107
##   beta[2]  -0.219480156 0.1359879
##   beta[3]   6.753539723 7.6918565
##   beta[4]   3.958222260 5.1256928
##   beta[5]   0.048715373 0.6263669
##   beta[6]   0.123970373 0.8158556
##   beta[7]  -0.108916631 0.2396658
##   beta[8]   0.462749833 2.6190701
##   beta[9]   6.262879770 7.5699975
##   beta[10]  0.452775990 1.4821986
##   beta[11]  0.386104985 1.4796341
##   beta[12]  0.239860128 1.4721086
##   beta[13]  0.183870987 0.8661887
##   beta[14]  0.085981820 0.8293149
##   beta[15]  0.079104414 0.7672477
##   beta[16]  0.176755078 1.2008877
##   beta[17]  0.166958617 1.5469094
##   beta[18]  0.023980797 0.3547857
##   beta[19]  1.444030259 2.7699559
##   beta[20]  2.221146338 3.1955100
##   beta[21]  0.405801184 1.5934931
##   beta[22]  0.427770522 1.5264643
##   beta[23]  0.133454834 1.2057563
##   beta[24]  0.052363405 0.5142723
##   beta[25]  0.163283436 1.1070839
##   beta[26]  0.171119789 0.9861635
##   beta[27]  0.569746754 1.9486539
##   beta[28]  0.495476000 1.8359045
##   beta[29]  0.915932460 2.1086850
##   beta[30]  0.245488904 1.4748635
##   beta[31]  0.141521493 1.1060428
##   beta[32]  0.033750074 0.5725048
##   beta[33]  0.637599060 2.1788309
##   beta[34]  0.047570696 0.6775789
##   beta[35]  0.173489868 1.1258985
##   beta[36]  0.114929918 0.9035003
##   beta[37]  1.442753639 2.9184586
##   beta[38]  0.107406178 0.7405671
##   beta[39]  0.182156512 0.9006361
##   beta[40]  0.131999766 0.6813869
##   beta[41]  0.210202588 1.0826572
##   beta[42]  0.126821678 0.7956051
##   beta[43]  0.494667980 1.6654642
##   beta[44]  0.256563058 1.2208613
##   beta[45]  0.185328260 1.0157769
##   beta[46]  0.251881373 1.4516300
##   beta[47]  0.049968428 0.4965543
##   beta[48]  0.167598331 1.2014494
##   beta[49]  0.006673464 0.3849180
##   beta[50]  0.139547981 1.1774987
##   beta[51]  0.175404390 1.0068335
##   beta[52]  0.024020548 0.5023666
##   beta[53]  0.062279336 0.6131920
##   beta[54]  0.161521640 1.0709493
##   beta[55]  0.112323031 0.7027262
##   beta[56]  0.076417423 1.1266927
##   beta[57]  0.346198860 2.1056311
##   beta[58]  0.161877150 1.1830645
##   beta[59]  0.082222116 0.7283482
##   beta[60]  0.238494171 1.1725869
##   beta[61]  0.158928347 1.0112642
##   beta[62]  0.068269690 0.6864417
##   beta[63]  0.220449521 1.1065933
##   beta[64]  0.287554847 1.5175220
## 
## , , chains = chain:2
## 
##           stats
## parameter         mean         sd        2.5%          25%           50%
##   b0        0.11700368 0.03353602  0.05334356  0.093464483  0.1171334869
##   sigma     0.59437031 0.02565391  0.54977346  0.576303140  0.5931940490
##   beta[1]   0.21574604 0.45507440 -0.39333388 -0.026221112  0.0651109976
##   beta[2]  -1.37796022 1.03200276 -3.33921693 -2.178884880 -1.3431104809
##   beta[3]   5.90711163 0.89702148  4.06890132  5.300921511  5.9371418130
##   beta[4]   3.42006518 0.93397321  1.62511001  2.846094441  3.4593885517
##   beta[5]  -0.20293207 0.66339464 -2.10009133 -0.232774311 -0.0348956834
##   beta[6]  -0.02594325 0.53581105 -1.20278930 -0.188091402 -0.0025857400
##   beta[7]  -1.48918197 1.28105147 -3.96014194 -2.535965313 -1.4132037908
##   beta[8]   0.29168559 0.81804153 -0.87424558 -0.061466218  0.0440691561
##   beta[9]   5.63145794 0.96133017  3.64650702  4.957251790  5.6264804383
##   beta[10]  0.28576845 0.51084171 -0.36520014 -0.010889851  0.0961004768
##   beta[11]  0.21410558 0.44052059 -0.37111091 -0.020696404  0.0738838506
##   beta[12]  0.14017289 0.44304383 -0.60099932 -0.065608470  0.0254963686
##   beta[13]  0.03711877 0.35662895 -0.73621498 -0.085916304  0.0094787110
##   beta[14] -0.02114432 0.42145561 -1.01389916 -0.149061740 -0.0001306631
##   beta[15] -0.07928484 0.43451986 -1.06498206 -0.201455057 -0.0156984465
##   beta[16]  0.04691448 0.42431412 -0.82479684 -0.096021373  0.0078611856
##   beta[17]  0.02691705 0.51583370 -1.11830441 -0.102089376  0.0084959870
##   beta[18] -0.22329225 0.52621435 -1.68356678 -0.340398866 -0.0770407492
##   beta[19]  0.63902939 0.76441473 -0.24456534  0.025826999  0.3557242937
##   beta[20]  1.46333968 0.95443161 -0.06568333  0.657754433  1.5913957181
##   beta[21]  0.20473152 0.44808457 -0.36128334 -0.034436462  0.0549946737
##   beta[22]  0.31888269 0.53005031 -0.28406273 -0.013147766  0.1163277680
##   beta[23]  0.04158009 0.51627973 -0.87302948 -0.117148458 -0.0004828796
##   beta[24] -0.18852216 0.58715435 -1.98370123 -0.260416806 -0.0296248058
##   beta[25]  0.05991372 0.37912122 -0.58481929 -0.082407630  0.0085045638
##   beta[26]  0.04076668 0.40514812 -0.77041421 -0.086490606  0.0084384085
##   beta[27]  0.31831665 0.61448749 -0.43106648 -0.011184015  0.0934383814
##   beta[28]  0.32277741 0.56495674 -0.35570687 -0.005936266  0.1180529007
##   beta[29]  0.47251723 0.68935988 -0.33452366  0.001657081  0.2056432231
##   beta[30]  0.13055830 0.40569448 -0.48564289 -0.048208547  0.0271278701
##   beta[31]  0.11491135 0.47648051 -0.64708262 -0.043996483  0.0331833140
##   beta[32] -0.14140679 0.45127243 -1.20812815 -0.273725399 -0.0440435403
##   beta[33]  0.36559151 0.60762037 -0.31976801 -0.001799520  0.1458983274
##   beta[34] -0.11960839 0.46988491 -1.37509330 -0.198497835 -0.0192697708
##   beta[35]  0.04487698 0.36759699 -0.62152123 -0.106832071  0.0038268191
##   beta[36]  0.00149953 0.36074943 -0.80378462 -0.131770923 -0.0019368929
##   beta[37]  0.85279999 0.84149863 -0.19897903  0.146734648  0.6879734760
##   beta[38] -0.01255656 0.42905045 -1.06348762 -0.118487978 -0.0026974741
##   beta[39]  0.01428739 0.43782762 -0.87786520 -0.161371222 -0.0004855222
##   beta[40] -0.04511237 0.40157181 -1.08377620 -0.167397041 -0.0053258459
##   beta[41]  0.03570077 0.40506371 -0.69186437 -0.119303416  0.0018596333
##   beta[42]  0.03938623 0.33256834 -0.69745548 -0.072538580  0.0079608455
##   beta[43]  0.33689049 0.61895164 -0.38704730 -0.015653830  0.1132787248
##   beta[44]  0.08334928 0.43763292 -0.60279161 -0.076046821  0.0058204884
##   beta[45]  0.08394594 0.41478585 -0.61080853 -0.071781898  0.0153479975
##   beta[46]  0.20940871 0.48548527 -0.60121487 -0.014599919  0.0723689519
##   beta[47] -0.11294496 0.43028643 -1.37678299 -0.170373456 -0.0198373148
##   beta[48]  0.01695269 0.36403207 -0.83949809 -0.099172498 -0.0019284308
##   beta[49] -0.12952727 0.45147295 -1.36091610 -0.250194691 -0.0328722607
##   beta[50] -0.02617809 0.43203212 -0.96839743 -0.188654107 -0.0065458175
##   beta[51]  0.07801673 0.48567025 -0.74463816 -0.070774948  0.0107994132
##   beta[52] -0.39025870 0.91192825 -2.83363506 -0.505118031 -0.0898187987
##   beta[53] -0.13741642 0.52385910 -1.53542706 -0.222670580 -0.0192929656
##   beta[54]  0.04372149 0.41717610 -0.77175139 -0.085998644  0.0099002810
##   beta[55] -0.06545479 0.43368701 -1.14885142 -0.119447404 -0.0021880892
##   beta[56] -0.01194014 0.49052193 -1.17674261 -0.142048505 -0.0005135052
##   beta[57]  0.29426496 0.60800431 -0.43710052 -0.026523814  0.0707825115
##   beta[58]  0.02128643 0.37719926 -0.73546554 -0.127529669 -0.0003893808
##   beta[59] -0.16130618 0.51602130 -1.62951943 -0.282060267 -0.0329736202
##   beta[60]  0.06359052 0.38392254 -0.59250223 -0.086919024  0.0017131526
##   beta[61]  0.04810718 0.40786928 -0.84328004 -0.076984896  0.0171186421
##   beta[62] -0.17020347 0.51933078 -1.51862262 -0.261761037 -0.0333879173
##   beta[63]  0.14200684 0.48832525 -0.64366383 -0.060248081  0.0257597714
##   beta[64]  0.21202104 0.50673222 -0.54264563 -0.036577064  0.0397056742
##           stats
## parameter          75%     97.5%
##   b0        0.14009363 0.1808023
##   sigma     0.61172726 0.6440250
##   beta[1]   0.34279494 1.4346590
##   beta[2]  -0.47585422 0.0976789
##   beta[3]   6.49406429 7.5896978
##   beta[4]   4.06234392 5.1624355
##   beta[5]   0.07336626 0.6063572
##   beta[6]   0.12154870 1.0001408
##   beta[7]  -0.24939128 0.1964458
##   beta[8]   0.47205463 2.3980500
##   beta[9]   6.30827596 7.3955558
##   beta[10]  0.45976877 1.6147688
##   beta[11]  0.39062558 1.3465506
##   beta[12]  0.26291096 1.4010626
##   beta[13]  0.16149849 0.9528715
##   beta[14]  0.11135825 0.7930066
##   beta[15]  0.07229454 0.6238302
##   beta[16]  0.19105181 0.9584164
##   beta[17]  0.16380217 1.2501508
##   beta[18]  0.03795068 0.5247262
##   beta[19]  1.12235127 2.4747398
##   beta[20]  2.13836759 3.1728710
##   beta[21]  0.38110577 1.4097932
##   beta[22]  0.51689043 1.8007014
##   beta[23]  0.13041111 1.1059266
##   beta[24]  0.03954035 0.5004477
##   beta[25]  0.15938727 1.0436599
##   beta[26]  0.15350066 0.8718489
##   beta[27]  0.48168865 2.1787504
##   beta[28]  0.53734353 1.8817121
##   beta[29]  0.82960948 2.1291190
##   beta[30]  0.21642111 1.2589602
##   beta[31]  0.21273154 1.2184840
##   beta[32]  0.03682028 0.4503352
##   beta[33]  0.57112951 1.8744222
##   beta[34]  0.05490169 0.5961484
##   beta[35]  0.15926106 0.9211402
##   beta[36]  0.10408326 0.8934775
##   beta[37]  1.35962251 2.7269444
##   beta[38]  0.10416500 0.9515588
##   beta[39]  0.18328095 1.0435342
##   beta[40]  0.09880046 0.6902301
##   beta[41]  0.14235787 0.9330629
##   beta[42]  0.13575256 0.8873242
##   beta[43]  0.50556808 2.1163137
##   beta[44]  0.15664301 1.1572616
##   beta[45]  0.19718956 0.9244804
##   beta[46]  0.38601304 1.4100361
##   beta[47]  0.05918640 0.5337084
##   beta[48]  0.13435911 0.8776842
##   beta[49]  0.06017663 0.5853681
##   beta[50]  0.09200781 1.0427907
##   beta[51]  0.15548214 1.3092389
##   beta[52]  0.02073028 0.5875628
##   beta[53]  0.07059298 0.6533243
##   beta[54]  0.16517352 0.9084686
##   beta[55]  0.07618251 0.6368469
##   beta[56]  0.11837569 1.0173015
##   beta[57]  0.46153271 2.0124076
##   beta[58]  0.13000613 0.9224123
##   beta[59]  0.05727591 0.6530307
##   beta[60]  0.16254185 1.0952350
##   beta[61]  0.16222772 0.9245533
##   beta[62]  0.05151175 0.5890174
##   beta[63]  0.23478181 1.3308912
##   beta[64]  0.32159327 1.5616917
## 
## , , chains = chain:3
## 
##           stats
## parameter          mean         sd        2.5%           25%           50%
##   b0        0.117211930 0.03421689  0.04228873  0.0980048854  0.1179155125
##   sigma     0.593016443 0.02488992  0.54903352  0.5747841926  0.5920583722
##   beta[1]   0.239426190 0.45055601 -0.33874947 -0.0173997797  0.0723917713
##   beta[2]  -1.384782069 0.97687706 -3.28628028 -2.0568001852 -1.3709135863
##   beta[3]   5.925733971 0.92945034  4.06027577  5.3527563262  5.9560949015
##   beta[4]   3.461777697 0.91386840  1.52893097  2.8957085508  3.5260861153
##   beta[5]  -0.223365946 0.61915879 -1.80903416 -0.3260037407 -0.0556012328
##   beta[6]   0.032789453 0.49321139 -0.77231822 -0.1206952685  0.0005430309
##   beta[7]  -1.451428954 1.16605311 -3.86103814 -2.2967377009 -1.2980626738
##   beta[8]   0.287041710 0.71296628 -0.77738008 -0.0349350380  0.0696519889
##   beta[9]   5.728237854 0.91450374  3.78202878  5.1338840549  5.7286242442
##   beta[10]  0.303835500 0.52713677 -0.34404284 -0.0095969307  0.1125213046
##   beta[11]  0.206649161 0.46687833 -0.46293851 -0.0383195101  0.0654404618
##   beta[12]  0.115569933 0.45548445 -0.73200612 -0.0611382884  0.0244132944
##   beta[13]  0.051133267 0.40707200 -0.85349652 -0.0856841218  0.0223165463
##   beta[14] -0.062130133 0.53143386 -1.28323009 -0.2135466090 -0.0171076233
##   beta[15] -0.066508896 0.43391616 -1.13087622 -0.1485173725 -0.0070090301
##   beta[16]  0.064915571 0.44891892 -0.86481885 -0.0980074264  0.0151369812
##   beta[17]  0.070134780 0.46542348 -0.63819455 -0.1016143065  0.0024716048
##   beta[18] -0.310934791 0.54662216 -1.97998995 -0.4645669810 -0.0896923501
##   beta[19]  0.744161145 0.86546695 -0.33110028  0.0158057404  0.5211671705
##   beta[20]  1.567717005 0.96060041 -0.03800707  0.8324687838  1.6011561493
##   beta[21]  0.233200329 0.48739749 -0.41320456 -0.0261063737  0.0781771687
##   beta[22]  0.304089441 0.53732073 -0.38088316 -0.0049959529  0.1095242294
##   beta[23] -0.024562143 0.43253956 -0.86014279 -0.1564972778 -0.0043593648
##   beta[24] -0.075904021 0.48899941 -1.21690568 -0.1695990261 -0.0068475826
##   beta[25]  0.050835088 0.34003020 -0.55889222 -0.0855222924  0.0091261736
##   beta[26]  0.076469629 0.46752735 -0.79435520 -0.0994832256  0.0096722884
##   beta[27]  0.301557885 0.54281324 -0.40834959 -0.0042886766  0.1187882690
##   beta[28]  0.276882895 0.55883274 -0.54311707 -0.0206120739  0.1108792639
##   beta[29]  0.523720525 0.66465738 -0.23751045  0.0128877942  0.2916295696
##   beta[30]  0.152986111 0.40556957 -0.48218227 -0.0501979814  0.0485275968
##   beta[31]  0.075513896 0.45539464 -0.64904807 -0.0800772923  0.0090700494
##   beta[32] -0.118887018 0.45520452 -1.32053050 -0.2225378354 -0.0314238517
##   beta[33]  0.385882951 0.62899502 -0.36740388 -0.0009280956  0.1280267663
##   beta[34] -0.190687669 0.51865860 -1.66410364 -0.2923272395 -0.0345046994
##   beta[35]  0.062069865 0.38028888 -0.70398626 -0.0999426614  0.0137684621
##   beta[36]  0.006640492 0.30927277 -0.65290669 -0.0911018821  0.0018792850
##   beta[37]  0.851220775 0.89995367 -0.25052070  0.0866024204  0.6143281858
##   beta[38] -0.001305088 0.42534711 -0.99176220 -0.1482712575  0.0092514428
##   beta[39]  0.047655458 0.36654260 -0.65900029 -0.0781453989  0.0054973294
##   beta[40] -0.061206919 0.41663239 -0.99894685 -0.1830049355 -0.0292476846
##   beta[41]  0.033133015 0.40929750 -0.88147679 -0.1177346000  0.0031928372
##   beta[42]  0.038709008 0.38168446 -0.74759618 -0.0992509137  0.0112587825
##   beta[43]  0.298725496 0.57653191 -0.29233256 -0.0157960483  0.0748123000
##   beta[44]  0.119931964 0.40423814 -0.48168406 -0.0606400032  0.0209954384
##   beta[45]  0.049180333 0.35665785 -0.62322581 -0.0823850780  0.0147972508
##   beta[46]  0.138577413 0.39480982 -0.37528456 -0.0605096845  0.0317198607
##   beta[47] -0.110046004 0.44241266 -1.29788738 -0.1792553958 -0.0243404194
##   beta[48]  0.013633809 0.41946556 -0.98062287 -0.0950265425  0.0026828589
##   beta[49] -0.152218022 0.50652527 -1.56889151 -0.2985141274 -0.0248721388
##   beta[50] -0.049314558 0.44537674 -1.08661077 -0.1548265816 -0.0071259080
##   beta[51]  0.086272852 0.48607940 -0.82870068 -0.1086786227  0.0203827180
##   beta[52] -0.412718098 0.81169287 -2.64807084 -0.6102113284 -0.1084338349
##   beta[53] -0.086092133 0.47368743 -1.39198698 -0.1981969349 -0.0163199706
##   beta[54]  0.085869637 0.47083275 -0.95574501 -0.0928784133  0.0282911822
##   beta[55] -0.108320858 0.49890818 -1.39476812 -0.1924503287 -0.0325615404
##   beta[56] -0.006704827 0.54449616 -1.19435237 -0.1323200163  0.0014778714
##   beta[57]  0.222779863 0.58308156 -0.63985923 -0.0409921092  0.0605777382
##   beta[58]  0.060121528 0.40340179 -0.63517553 -0.0828992774  0.0194292082
##   beta[59] -0.157899071 0.46234468 -1.30060688 -0.2888640620 -0.0296772720
##   beta[60]  0.079515816 0.42310027 -0.75259512 -0.0592294535  0.0089476843
##   beta[61]  0.048482942 0.40713299 -0.70970575 -0.1297859183  0.0067506640
##   beta[62] -0.123349385 0.49028962 -1.28754890 -0.2724040384 -0.0218665867
##   beta[63]  0.079466408 0.42853479 -0.79624467 -0.0863342117  0.0139482050
##   beta[64]  0.199827444 0.49507917 -0.42305869 -0.0586137218  0.0364478214
##           stats
## parameter           75%     97.5%
##   b0        0.137630862 0.1846683
##   sigma     0.610484911 0.6410159
##   beta[1]   0.382680020 1.4576994
##   beta[2]  -0.559023886 0.0656651
##   beta[3]   6.519073225 7.7507841
##   beta[4]   4.079900949 5.1284161
##   beta[5]   0.039249769 0.5301274
##   beta[6]   0.138544120 1.2209746
##   beta[7]  -0.398621833 0.1322502
##   beta[8]   0.387673029 2.1859544
##   beta[9]   6.376723120 7.4362379
##   beta[10]  0.489581405 1.7525013
##   beta[11]  0.360093042 1.4409621
##   beta[12]  0.230585161 1.2023046
##   beta[13]  0.168365720 1.0018304
##   beta[14]  0.092685696 0.8448011
##   beta[15]  0.087220708 0.7589274
##   beta[16]  0.154030683 1.0873559
##   beta[17]  0.168035475 1.1461920
##   beta[18]  0.007768468 0.2579907
##   beta[19]  1.292048352 2.8026648
##   beta[20]  2.255672591 3.2760538
##   beta[21]  0.407905523 1.5875672
##   beta[22]  0.470076690 1.8152382
##   beta[23]  0.095670886 0.7407418
##   beta[24]  0.098893803 0.6771375
##   beta[25]  0.149919607 0.8665751
##   beta[26]  0.205547600 1.2210816
##   beta[27]  0.513373528 1.6869136
##   beta[28]  0.511393700 1.6673772
##   beta[29]  0.854333346 2.1831297
##   beta[30]  0.294544341 1.2829564
##   beta[31]  0.198079283 1.0941303
##   beta[32]  0.060739060 0.6591190
##   beta[33]  0.614183645 2.0686089
##   beta[34]  0.054019941 0.4973491
##   beta[35]  0.211492515 0.8785518
##   beta[36]  0.118815971 0.6551909
##   beta[37]  1.364272562 2.9993450
##   beta[38]  0.176288406 0.8757562
##   beta[39]  0.144109521 1.0410310
##   beta[40]  0.092170197 0.7138132
##   beta[41]  0.158036228 1.0031430
##   beta[42]  0.181884990 0.9483663
##   beta[43]  0.471561713 1.9179321
##   beta[44]  0.206823335 1.1093639
##   beta[45]  0.170205735 0.9557815
##   beta[46]  0.250824796 1.0633499
##   beta[47]  0.048856839 0.6848795
##   beta[48]  0.153046180 0.9969507
##   beta[49]  0.068858159 0.6385081
##   beta[50]  0.110694158 0.7815792
##   beta[51]  0.244110976 1.2070675
##   beta[52]  0.025072709 0.5412989
##   beta[53]  0.103516586 0.6693265
##   beta[54]  0.241300505 1.2269507
##   beta[55]  0.060695467 0.6877377
##   beta[56]  0.143390045 0.9015386
##   beta[57]  0.326473986 1.9449162
##   beta[58]  0.173277101 0.9442381
##   beta[59]  0.069215058 0.5697033
##   beta[60]  0.179290435 1.2279574
##   beta[61]  0.167315885 1.1121824
##   beta[62]  0.073123871 0.7567029
##   beta[63]  0.212703742 1.0866923
##   beta[64]  0.331235884 1.4637496
## 
## , , chains = chain:4
## 
##           stats
## parameter          mean         sd        2.5%         25%           50%
##   b0        0.117519469 0.03035432  0.05525244  0.09856493  0.1184914781
##   sigma     0.593940309 0.02526376  0.54541130  0.57550953  0.5926558757
##   beta[1]   0.179615793 0.41383157 -0.44249348 -0.04168520  0.0450986989
##   beta[2]  -1.341739263 1.01079001 -3.43359214 -2.06443508 -1.2726641106
##   beta[3]   5.920308897 1.01602193  3.91894702  5.24383326  5.9198101098
##   beta[4]   3.440390270 1.01849382  1.36660875  2.73082890  3.4421125659
##   beta[5]  -0.239166559 0.62656578 -1.86462890 -0.29837404 -0.0570408501
##   beta[6]   0.023410550 0.46716548 -0.81604497 -0.15586629  0.0027756213
##   beta[7]  -1.464682336 1.32461538 -4.38053913 -2.45808462 -1.2724755340
##   beta[8]   0.269691418 0.78298562 -0.85390691 -0.07096664  0.0604022469
##   beta[9]   5.704189503 1.00012740  3.69248322  5.08440897  5.6835886180
##   beta[10]  0.282340584 0.52796416 -0.42571745 -0.01833501  0.1090340619
##   beta[11]  0.240089320 0.46662439 -0.32612307 -0.01934673  0.0894592898
##   beta[12]  0.159429617 0.46343183 -0.59066010 -0.02976330  0.0389276211
##   beta[13]  0.022511382 0.41121425 -0.94427574 -0.10836127  0.0027725883
##   beta[14] -0.086335357 0.49166403 -1.19496882 -0.17887674 -0.0177686637
##   beta[15] -0.055346655 0.47605515 -1.13223575 -0.22096687 -0.0135936038
##   beta[16]  0.005230051 0.41969305 -0.96036006 -0.12925795  0.0013862497
##   beta[17]  0.034014010 0.49467654 -0.99747521 -0.12711643  0.0029343327
##   beta[18] -0.256033490 0.48120102 -1.63470912 -0.42343611 -0.0955341129
##   beta[19]  0.768313436 0.85946064 -0.24175026  0.07412252  0.5192398816
##   beta[20]  1.447850807 0.90922154 -0.04904268  0.76987261  1.4918425670
##   beta[21]  0.202538391 0.47662038 -0.53148476 -0.03770957  0.0682784352
##   beta[22]  0.264195975 0.52170578 -0.45966592 -0.02122369  0.0739829482
##   beta[23] -0.035328660 0.46295355 -1.17635742 -0.15896096 -0.0047886236
##   beta[24] -0.135136051 0.43906860 -1.36726267 -0.24923418 -0.0378694976
##   beta[25]  0.012385462 0.38014944 -0.85667368 -0.11587662  0.0038956300
##   beta[26]  0.064035182 0.43183308 -0.75949794 -0.07823593  0.0077186089
##   beta[27]  0.350312081 0.60867730 -0.35710391 -0.00931301  0.1072947646
##   beta[28]  0.285449183 0.53732996 -0.34675260 -0.03362351  0.0983562721
##   beta[29]  0.523217834 0.62464697 -0.17252727  0.03676941  0.3116126918
##   beta[30]  0.194801686 0.48263923 -0.57783609 -0.03149360  0.0531216685
##   beta[31]  0.100570542 0.41510237 -0.70360677 -0.06093187  0.0273609800
##   beta[32] -0.103649155 0.45777995 -1.22690337 -0.21503308 -0.0208595893
##   beta[33]  0.390768029 0.66724635 -0.41510284 -0.01143072  0.1374526547
##   beta[34] -0.172225375 0.47211975 -1.33738927 -0.34096434 -0.0632531099
##   beta[35]  0.059484228 0.40601259 -0.63591925 -0.07223196  0.0156495183
##   beta[36]  0.002861430 0.34656595 -0.73388072 -0.11736268 -0.0004250478
##   beta[37]  0.812596954 0.86408767 -0.19603471  0.06538405  0.5391568825
##   beta[38]  0.004796273 0.38168308 -0.81383979 -0.09857990  0.0061500344
##   beta[39]  0.019665390 0.37659734 -0.77802615 -0.12088100 -0.0011956530
##   beta[40] -0.024916788 0.39294222 -0.87973793 -0.15010590 -0.0009477866
##   beta[41]  0.032342127 0.40674437 -0.80076078 -0.10900027  0.0042900809
##   beta[42]  0.020339485 0.37711929 -0.77646749 -0.13429645  0.0106823733
##   beta[43]  0.311887698 0.61351033 -0.54374047 -0.03904227  0.1277179108
##   beta[44]  0.147803465 0.43075899 -0.49206164 -0.04582191  0.0231304029
##   beta[45]  0.072552956 0.40756571 -0.73925143 -0.06524679  0.0128334215
##   beta[46]  0.128860940 0.46162575 -0.61034761 -0.06892541  0.0211067515
##   beta[47] -0.143613525 0.42491843 -1.20302114 -0.28996648 -0.0428493940
##   beta[48]  0.053127912 0.41038703 -0.77189941 -0.09326946  0.0174537413
##   beta[49] -0.181033172 0.51662708 -1.67892347 -0.24814857 -0.0339255774
##   beta[50] -0.007356024 0.51332035 -1.13816492 -0.13913158 -0.0019693840
##   beta[51]  0.103674507 0.45574859 -0.64930173 -0.06340935  0.0249000288
##   beta[52] -0.397443647 0.79239864 -2.59605504 -0.51515906 -0.0985691353
##   beta[53] -0.137461294 0.46344648 -1.34258521 -0.25796484 -0.0369704677
##   beta[54]  0.057384413 0.38899804 -0.80840079 -0.07331096  0.0135601413
##   beta[55] -0.095653482 0.43174941 -1.19589584 -0.20162925 -0.0237182072
##   beta[56] -0.022009398 0.53185646 -1.24520768 -0.20008477 -0.0195061798
##   beta[57]  0.259539663 0.58256378 -0.52450971 -0.03406319  0.0749261368
##   beta[58]  0.008043106 0.41114697 -0.96423673 -0.11294262  0.0004317950
##   beta[59] -0.209830045 0.55394259 -1.54396388 -0.36323334 -0.0575785625
##   beta[60]  0.121158146 0.44713940 -0.61550858 -0.07975137  0.0316162707
##   beta[61]  0.060877653 0.42338685 -0.69692464 -0.09756042  0.0081115693
##   beta[62] -0.158732655 0.46372426 -1.38733954 -0.27279831 -0.0441388195
##   beta[63]  0.212137206 0.53185626 -0.62384274 -0.03049782  0.0605691206
##   beta[64]  0.130969624 0.43966716 -0.51687821 -0.05678928  0.0224606878
##           stats
## parameter          75%      97.5%
##   b0        0.13627885 0.17931244
##   sigma     0.61127831 0.64406679
##   beta[1]   0.33779499 1.23489559
##   beta[2]  -0.43914097 0.07779334
##   beta[3]   6.55787708 7.93099186
##   beta[4]   4.19204558 5.24484418
##   beta[5]   0.04207556 0.50546463
##   beta[6]   0.14077929 1.15724627
##   beta[7]  -0.20032525 0.16556770
##   beta[8]   0.37491545 2.51860493
##   beta[9]   6.43599375 7.47834519
##   beta[10]  0.47536002 1.65628191
##   beta[11]  0.40512069 1.60918191
##   beta[12]  0.26441674 1.58236688
##   beta[13]  0.15856691 0.97897495
##   beta[14]  0.09628888 0.66648204
##   beta[15]  0.08888243 0.94087006
##   beta[16]  0.12853374 1.01245940
##   beta[17]  0.16738211 1.24575104
##   beta[18]  0.02334925 0.33250434
##   beta[19]  1.28854722 2.84955142
##   beta[20]  2.07469906 3.14761257
##   beta[21]  0.36308810 1.46978394
##   beta[22]  0.44370961 1.56429405
##   beta[23]  0.10872034 0.78248625
##   beta[24]  0.05373450 0.56320552
##   beta[25]  0.15294060 0.79279435
##   beta[26]  0.16167270 1.10009806
##   beta[27]  0.57330324 2.06397330
##   beta[28]  0.46754986 1.71829294
##   beta[29]  0.88454198 2.09269610
##   beta[30]  0.33684811 1.45945814
##   beta[31]  0.22031567 1.05562920
##   beta[32]  0.09059306 0.56521703
##   beta[33]  0.58679816 2.16443877
##   beta[34]  0.03156464 0.72155363
##   beta[35]  0.17182639 1.03560172
##   beta[36]  0.10848173 0.74909167
##   beta[37]  1.38622861 2.67476397
##   beta[38]  0.13253639 0.81234241
##   beta[39]  0.14055588 0.98786354
##   beta[40]  0.14213463 0.69374729
##   beta[41]  0.16582284 1.09339846
##   beta[42]  0.16888339 0.81354933
##   beta[43]  0.54657710 1.97314785
##   beta[44]  0.26648612 1.36381340
##   beta[45]  0.18219956 1.19497699
##   beta[46]  0.23469159 1.31558393
##   beta[47]  0.04451061 0.55862822
##   beta[48]  0.18974100 1.04333768
##   beta[49]  0.05449825 0.43208694
##   beta[50]  0.12650881 1.14729784
##   beta[51]  0.21927304 1.15329573
##   beta[52]  0.02453860 0.41752836
##   beta[53]  0.06204604 0.59342842
##   beta[54]  0.17099439 1.02455804
##   beta[55]  0.07514839 0.71364120
##   beta[56]  0.08868690 1.19522880
##   beta[57]  0.42094299 1.91395086
##   beta[58]  0.13763922 0.95952793
##   beta[59]  0.04002773 0.62946734
##   beta[60]  0.24787389 1.32430368
##   beta[61]  0.21405362 1.09432388
##   beta[62]  0.05200005 0.50004587
##   beta[63]  0.36938600 1.59020944
##   beta[64]  0.22727702 1.22459846

First compare the resulting regression parameters to OLS values.

plot of chunk compare_betas

The coefficient estimates from OLS are wierd.

##                       ols          stan
## (Intercept)   150.6877158  151.62322346
## tc          -5344.1362146   -4.13948456
## `tc:ldl`    -4837.7577691   -0.46036150
## ldl          4723.0001852   -0.03713766
## `tc^2`       4501.3147154   -0.98157640
## ltg          2350.5648361  514.73662718
## `tc:hdl`    -2183.9679154    1.58850954
## `tc:ltg`    -2127.4763989   -2.17047968
## `tc:tch`    -2109.4859422   -8.71594752
## hdl          1680.5383464 -113.15691407
## `hdl:tch`    1423.4283796   -2.92198156
## `ldl^2`      1315.3475569   -1.45697679
## `ldl:ltg`    1301.0314400    5.69924375
## `tch^2`      1153.5055778    0.36458560
## `ltg^2`      1092.0802627   -7.65377146
## `hdl^2`      1030.4183629    0.83444186
## `ldl:glu`    -997.1769908    0.38170238
## `tc:glu`      950.9385270    1.05565719
## `ldl:hdl`     750.6734763   -1.36106213
## `sex:tc`      710.4735493    1.52061602
## `ldl:tch`     685.7207365   -0.82447499
## `sex:ldl`    -583.0899124   -3.01636137
## `hdl:ltg`     579.6892310    1.32283252
## bmi           472.7822071  538.51375738
## `bmi:tc`     -449.8107181    0.17764949
## `bmi:ldl`     449.7137136    0.38615369
## `age:tc`     -381.4352029   -0.17616836
## map           360.8679843  311.19193304
## sex          -269.6337058 -116.02178916
## `ltg:glu`    -262.9689424    2.79866627
## `map:glu`    -244.4812374   -3.77154112
## `bmi:map`     232.7826663   55.67845064
## `tch:ltg`     231.5833277   -2.56513667
## `age:ltg`     226.9633990   10.72231703
## `age:ldl`     210.2181540   -2.52040030
## `sex:ltg`    -210.1018253    0.95139364
## `hdl:glu`    -207.1878927    1.07578340
## `age:hdl`     200.9051940    0.58776431
## `tch:glu`     195.2469288    2.49312673
## `map:tc`      164.8892506    2.00290768
## `sex:bmi`     151.2507925   25.86593599
## `age:sex`     148.1955348  139.53985970
## `bmi:tch`    -132.9842910    0.50915513
## `bmi:ltg`     132.1057723    0.81541926
## `glu^2`       128.3359803   43.09992346
## `age:glu`     123.5654440    9.62138335
## `bmi:hdl`     123.4574377   -0.47452796
## `map:tch`    -114.1544438   -2.61278773
## glu            89.6525363    9.87636341
## `sex:hdl`     -89.0422237   12.99307577
## `bmi:glu`      88.7749691    9.48374612
## tch           -85.1837399    5.05488885
## age            84.9492352    5.27733808
## `map:hdl`     -84.9267162    4.25471339
## `age^2`        66.3266859    6.56309345
## `sex:tch`     -61.9876132   -3.76450021
## `age:tch`      61.3931988    0.81214627
## `map^2`       -52.3896842    1.18138406
## `map:ldl`     -35.3650443    1.31070882
## `sex:map`      34.8982815    3.42459095
## `age:map`      20.5936704    9.62768861
## `bmi^2`       -15.8074138    2.48565599
## `map:ltg`       3.8402792    0.54223768
## `sex:glu`       2.2141893   -0.02030653
## `age:bmi`       0.2614859    5.67149734

And, quite different than what Stan gets.

##                       ols          stan
## (Intercept)   150.6877158  151.62322346
## bmi           472.7822071  538.51375738
## ltg          2350.5648361  514.73662718
## map           360.8679843  311.19193304
## `age:sex`     148.1955348  139.53985970
## sex          -269.6337058 -116.02178916
## hdl          1680.5383464 -113.15691407
## `bmi:map`     232.7826663   55.67845064
## `glu^2`       128.3359803   43.09992346
## `sex:bmi`     151.2507925   25.86593599
## `sex:hdl`     -89.0422237   12.99307577
## `age:ltg`     226.9633990   10.72231703
## glu            89.6525363    9.87636341
## `age:map`      20.5936704    9.62768861
## `age:glu`     123.5654440    9.62138335
## `bmi:glu`      88.7749691    9.48374612
## `tc:tch`    -2109.4859422   -8.71594752
## `ltg^2`      1092.0802627   -7.65377146
## `age^2`        66.3266859    6.56309345
## `ldl:ltg`    1301.0314400    5.69924375
## `age:bmi`       0.2614859    5.67149734
## age            84.9492352    5.27733808
## tch           -85.1837399    5.05488885
## `map:hdl`     -84.9267162    4.25471339
## tc          -5344.1362146   -4.13948456
## `map:glu`    -244.4812374   -3.77154112
## `sex:tch`     -61.9876132   -3.76450021
## `sex:map`      34.8982815    3.42459095
## `sex:ldl`    -583.0899124   -3.01636137
## `hdl:tch`    1423.4283796   -2.92198156
## `ltg:glu`    -262.9689424    2.79866627
## `map:tch`    -114.1544438   -2.61278773
## `tch:ltg`     231.5833277   -2.56513667
## `age:ldl`     210.2181540   -2.52040030
## `tch:glu`     195.2469288    2.49312673
## `bmi^2`       -15.8074138    2.48565599
## `tc:ltg`    -2127.4763989   -2.17047968
## `map:tc`      164.8892506    2.00290768
## `tc:hdl`    -2183.9679154    1.58850954
## `sex:tc`      710.4735493    1.52061602
## `ldl^2`      1315.3475569   -1.45697679
## `ldl:hdl`     750.6734763   -1.36106213
## `hdl:ltg`     579.6892310    1.32283252
## `map:ldl`     -35.3650443    1.31070882
## `map^2`       -52.3896842    1.18138406
## `hdl:glu`    -207.1878927    1.07578340
## `tc:glu`      950.9385270    1.05565719
## `tc^2`       4501.3147154   -0.98157640
## `sex:ltg`    -210.1018253    0.95139364
## `hdl^2`      1030.4183629    0.83444186
## `ldl:tch`     685.7207365   -0.82447499
## `bmi:ltg`     132.1057723    0.81541926
## `age:tch`      61.3931988    0.81214627
## `age:hdl`     200.9051940    0.58776431
## `map:ltg`       3.8402792    0.54223768
## `bmi:tch`    -132.9842910    0.50915513
## `bmi:hdl`     123.4574377   -0.47452796
## `tc:ldl`    -4837.7577691   -0.46036150
## `bmi:ldl`     449.7137136    0.38615369
## `ldl:glu`    -997.1769908    0.38170238
## `tch^2`      1153.5055778    0.36458560
## `bmi:tc`     -449.8107181    0.17764949
## `age:tc`     -381.4352029   -0.17616836
## ldl          4723.0001852   -0.03713766
## `sex:glu`       2.2141893   -0.02030653

Now let’s look at out-of-sample prediction error, using the posterior median coefficient estimates:

plot of chunk pred_stan

Conclusions?

  1. Our “sparse” model is certainly more sparse, and arguably more interpretable.

  2. It has a root-mean-square prediction error of 52.3500261 on the test data, and 52.8630837 on the training data.

  3. This is substantially better than ordinary linear regression, which had a root-mean-square prediction error of 61.3508494 on the test data, and a root-mean-square-error of 47.9132317 on the training data.

The sparse model is more interpretable, and more generalizable.

Exercises

Pick a situation

  1. Number of mosquitos caught in traps at 20 different time points at 4 locations; temperature and rainfall are also measured.

  2. Transpiration rates of 5 trees each of 100 strains, along with genotype at five SNPs putatively linked to stomatal efficiency.

  3. Presence or absence of Wolbachia parasites in fifty flies are sampled from each of 100 populations, along with the sex and transcription levels of ten immune-related genes of each fly.

  4. HW1/2: exponential regression

Mosquitos: variables

Big picture: We’re sampling mosquitos in a few separate (replicate) traps once, in the day and at night, each month, at each of four locations.

Main question: How do mosquito populations vary seasonally and by time of day, after controlling for temperature and rainfall?

Mosquitos: story

We’ve chosen locations to have similar rainfall and temperature means (so that location and rain/temp aren’t confounded).

There are more mosquitos out at night than during the day, and more when it is warmer and wetter, but there is no effect of month given temperature and rainfall. There is an overall mean difference in abundance by location, due to unmeasured factors.

Mosquitos: variables

  • count : number of mosquitos caught (0-1000)
  • rainfall : cm of rain in the last 12 hours (\(< 10\)cm)
  • temperature : average degrees C last 12 hours (25–35 C)
  • location : factor with four levels
  • time : day or night
  • month : categorical, 1–12 (note: could be numeric/sinusoidal!)
  • replicate : which trap number within the month/time/location combination (up to 5) (unused in the model)

Note: we’ll have around 480 observations and 20 variables (without interactions).