\[ %% % Add your macros here; they'll be included in pdf and html output. %% \newcommand{\R}{\mathbb{R}} % reals \newcommand{\E}{\mathbb{E}} % expectation \renewcommand{\P}{\mathbb{P}} % probability \DeclareMathOperator{\logit}{logit} \DeclareMathOperator{\logistic}{logistic} \DeclareMathOperator{\sd}{sd} \DeclareMathOperator{\var}{var} \DeclareMathOperator{\cov}{cov} \DeclareMathOperator{\Normal}{Normal} \DeclareMathOperator{\Poisson}{Poisson} \DeclareMathOperator{\Beta}{Beta} \DeclareMathOperator{\Binom}{Binomial} \DeclareMathOperator{\Gam}{Gamma} \DeclareMathOperator{\Exp}{Exponential} \DeclareMathOperator{\Cauchy}{Cauchy} \DeclareMathOperator{\Unif}{Unif} \DeclareMathOperator{\Dirichlet}{Dirichlet} \DeclareMathOperator{\Wishart}{Wishart} \newcommand{\given}{\;\vert\;} \]

GLMs, overdispersion, and goodness-of-fit

Peter Ralph

14 January 2018 – Advanced Biological Statistics

Generalized Linear Models

Ingredients of a GLM:

  1. A probability distribution, \(Y\).

(the “family”; describes the output)

  1. A linear predictor, \(X \beta\).

(connects input to output)

  1. A link function, \(\E[Y] = h(X\beta)\).

(connects linear predictor to probability distribution)

Common choices:

  • Linear regression: \[ Y \sim \Normal(X \beta, \sigma) .\]

  • Logistic regression: \[ Y \sim \Binom(n, \logistic(X\beta)) .\]

  • Gamma regression: \[ Y \sim \Gam(\text{scale}=\exp(X\beta)/k, \text{shape}=k) .\]

Logistic regression, in R

glm(y ~ x, family=binomial)
family {stats}

Family objects provide a convenient way to specify the details of the models used by functions such as glm.

binomial(link = "logit")
gaussian(link = "identity")
Gamma(link = "inverse")
inverse.gaussian(link = "1/mu^2")
poisson(link = "log")

Arguments

link: a specification for the model link function. This can be a name/expression, a literal character string, a length-one character vector, or an object of class "link-glm" (such as generated by make.link) provided it is not specified via one of the standard names given next.

The gaussian family accepts the links (as names) identity, log and inverse; the binomial family the links logit, probit, cauchit, (corresponding to logistic, normal and Cauchy CDFs respectively) log and cloglog (complementary log-log); the Gamma family the links inverse, identity and log; the poisson family the links log, identity, and sqrt; and the inverse.gaussian family the links 1/mu^2, inverse, identity and log.

Unpacking logistic regression

Simulate data

100 trials, where probability of success depends on \(x\):

plot of chunk sim_logistic

glm()

## 
## Call:
## glm(formula = zz ~ x, family = "binomial")
## 
## Deviance Residuals: 
##      Min        1Q    Median        3Q       Max  
## -1.79584  -0.14355   0.01418   0.07181   2.58115  
## 
## Coefficients:
##             Estimate Std. Error z value Pr(>|z|)    
## (Intercept)  -9.7512     2.4701  -3.948 7.89e-05 ***
## x             1.9531     0.4849   4.028 5.62e-05 ***
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
## 
## (Dispersion parameter for binomial family taken to be 1)
## 
##     Null deviance: 138.269  on 99  degrees of freedom
## Residual deviance:  28.807  on 98  degrees of freedom
## AIC: 32.807
## 
## Number of Fisher Scoring iterations: 7

Stan

Stan: fit the model

## $summary
##            mean    se_mean        sd       2.5%        25%        50%
## alpha -11.24967 0.10744784 2.6860590 -17.262303 -12.906310 -10.916415
## beta    2.24945 0.02105587 0.5264088   1.383928   1.870049   2.190549
## lp__  -15.43677 0.03147576 0.9731003 -18.089596 -15.870265 -15.147178
##              75%      97.5%    n_eff     Rhat
## alpha  -9.299297  -6.835742 624.9362 1.003205
## beta    2.571353   3.415786 625.0289 1.003971
## lp__  -14.714485 -14.426820 955.7903 1.003256
## 
## $c_summary
## , , chains = chain:1
## 
##          stats
## parameter       mean        sd       2.5%        25%        50%        75%
##     alpha -11.157536 2.5408466 -16.865943 -12.797324 -10.970090  -9.227163
##     beta    2.228253 0.5085301   1.386013   1.853273   2.190844   2.543871
##     lp__  -15.452112 0.9889446 -18.098891 -15.900315 -15.171180 -14.699103
##          stats
## parameter      97.5%
##     alpha  -6.814512
##     beta    3.356737
##     lp__  -14.429367
## 
## , , chains = chain:2
## 
##          stats
## parameter       mean        sd       2.5%        25%        50%        75%
##     alpha -11.463242 2.7812442 -17.865908 -13.021270 -11.042255  -9.489456
##     beta    2.297488 0.5393182   1.420122   1.902149   2.231015   2.622173
##     lp__  -15.415057 0.9809461 -18.181455 -15.834569 -15.146324 -14.674684
##          stats
## parameter      97.5%
##     alpha  -6.920368
##     beta    3.513544
##     lp__  -14.417750
## 
## , , chains = chain:3
## 
##          stats
## parameter       mean        sd       2.5%        25%       50%        75%
##     alpha -11.304196 2.7955471 -17.575864 -13.184845 -10.89553  -9.256249
##     beta    2.259235 0.5482089   1.298729   1.896051   2.20113   2.616746
##     lp__  -15.503305 1.0125950 -18.171424 -15.971176 -15.19399 -14.739261
##          stats
## parameter      97.5%
##     alpha  -6.510975
##     beta    3.466496
##     lp__  -14.432854
## 
## , , chains = chain:4
## 
##          stats
## parameter       mean        sd       2.5%        25%        50%        75%
##     alpha -11.073698 2.6051648 -16.940830 -12.582058 -10.759517  -9.194292
##     beta    2.212824 0.5050335   1.422149   1.843107   2.151902   2.508836
##     lp__  -15.376602 0.9034170 -17.754912 -15.735517 -15.096816 -14.728251
##          stats
## parameter      97.5%
##     alpha  -7.147461
##     beta    3.297399
##     lp__  -14.432523

Stan: posterior distributions

plot of chunk plot_stan_logistic

Identify the GLM

data {
  int N;
  vector[N] X;
  vector[N] Y;
  vector<lower=0> Z[N];
}
parameters {
  real beta[2];
}
model {
  Z ~ gamma(1, exp(- beta[1] * X - beta[2] * Y);
}

What is

  1. the probability distribution? (describes the output)

  2. the linear predictor? (connects input to output)

  3. the link function? (connects linear predictor to probability distribution)

Then, simulate from it.

Stochastic minute

The Poisson distribution

If \(N \sim \Poisson(\mu)\) then \(N \ge 0\) and \[\begin{aligned} \P\{N = k\} = \frac{\mu^k}{k!} e^{-\mu} \end{aligned}\]

  • \(N\) is a nonnegative integer (i.e., a count)

  • \(\E[N] = \var[N] = \mu\)

  • If a machine makes widgets very fast, producing on average one broken widget per minute (and many good ones), each breaking independent of the others, then the number of broken widgets in \(\mu\) minutes is \(\Poisson(\mu)\).

  • If busses arrive randomly every \(\Exp(1)\) minutes, then the number of busses to arrive in \(\mu\) minutes is \(\Poisson(\mu)\).

Count data

A hypothetical situation:

  1. We have counts of transcript numbers,

  2. from some individuals of different ages and past exposures to solar irradiation,

  3. of two genotypes.

Model:

  • Counts are Poisson,

  • with mean that depends on age and exposure,

  • but effect of exposure depends on genotype.

  1. Counts are Poisson,

  2. with mean that depends on age and exposure,

  3. but effect of exposure depends on genotype.

\[\begin{aligned} Z_i &\sim \Poisson(\mu_i) \\ \end{aligned}\]

  1. Counts are Poisson,

  2. with mean that depends on age and exposure,

  3. but effect of exposure depends on genotype.

\[\begin{aligned} Z_i &\sim \Poisson(\mu_i) \\ \mu_i &= a + b \times \text{age}_i + c \times \text{exposure}_i \end{aligned}\]

  1. Counts are Poisson,

  2. with mean that depends on age and exposure,

  3. but effect of exposure depends on genotype.

\[\begin{aligned} Z_i &\sim \Poisson(\mu_i) \\ \mu_i &= \exp\left( a_{g_i} + b \times \text{age}_i + c_{g_i} \times \text{exposure}_i \right) \end{aligned}\]

Poisson regression, in practice

The data

plot of chunk plot_counts

Write a Stan block

  1. Counts are Poisson,

  2. with mean that depends on age and exposure,

  3. but effect of exposure depends on genotype.

\[\begin{aligned} Z_i &\sim \Poisson(y_i) \\ y_i &= \exp(a_{g_i} + b \times \text{age}_i \\ &\qquad {} + c_{g_i} \times \text{exposure}_i ) \end{aligned}\]

poisson_model <- stan_model(model_code="
data {
    int N; // number of data points
    vector[N] age;
    vector[N] exposure;
    int counts[N];
    int genotype[N];
    int ngenotypes;
}
parameters {
    vector[ngenotypes] a; // intercepts
    real b; // slope for age
    vector[ngenotypes] c; // slopes for exposure
}
model {
    vector[N] mu; // mean of the poissons
    mu = exp(a[genotype] + b * age + c[genotype] .* exposure);
    counts ~ poisson(mu);
    a ~ normal(0, 100);
    b ~ normal(0, 10);
    c ~ normal(0, 20);
}")

The result

Note: scaling the data helps Stan find the right scale to move on.

## Inference for Stan model: simple_poisson.
## 3 chains, each with iter=1000; warmup=500; thin=1; 
## post-warmup draws per chain=500, total post-warmup draws=1500.
## 
##          mean se_mean   sd     2.5%      25%      50%      75%    97.5%
## a[1]     2.06    0.00 0.02     2.02     2.05     2.06     2.07     2.10
## a[2]     1.90    0.00 0.02     1.86     1.89     1.90     1.92     1.95
## b        0.84    0.00 0.01     0.82     0.84     0.84     0.85     0.87
## c[1]     0.26    0.00 0.02     0.23     0.25     0.26     0.27     0.29
## c[2]    -0.14    0.00 0.02    -0.18    -0.16    -0.14    -0.13    -0.10
## lp__ 10937.60    0.06 1.64 10933.70 10936.84 10937.90 10938.81 10939.70
##      n_eff Rhat
## a[1]  1218    1
## a[2]  1260    1
## b     1202    1
## c[1]  1487    1
## c[2]  1668    1
## lp__   727    1
## 
## Samples were drawn using NUTS(diag_e) at Sat Jan  5 12:59:06 2019.
## For each parameter, n_eff is a crude measure of effective sample size,
## and Rhat is the potential scale reduction factor on split chains (at 
## convergence, Rhat=1).

Aside: a look at “warmup”

plot of chunk the_warmup

The usual plot (without warmup)

plot of chunk not_warmup

How’d we do?

Here are posterior distributions of the parameters, with the true values in red. plot of chunk true_fit_1

What happened?

Goodness of fit

Posterior predictive simulations

Let’s simulate up data under this model to check for goodness of fit.

We expect to not see a good fit. (Why?)

100 datasets from the posterior distribution

True data are overdispersed relative to our simulations

plot of chunk plot_post_sims1

Stan interlude

The important program blocks

data {
    // what we know: the input
    // declarations only
}
parameters {
    // what we want to know about:
    // defines the space Stan random walks in
    // declarations only
}
model {
    // stuff to calculate the priors and the likelihoods
    // happens every step
}

The program blocks

functions {
    // user-defined functions
}
data {
    // what we know: the input
    // declarations only
}
transformed data {
    // calculations to do once, at the start
}
parameters {
    // what we want to know about:
    // defines the space Stan random walks in
    // declarations only
}
transformed parameters {
    // other things that we want the posterior distribution of
    // happens every step
}
model {
    // stuff to calculate the priors and the likelihoods
    // happens every step
}
generated quantities {
    // more things we want the posterior distribution of
    // but that don't affect the random walk
}

On priors

Under the hood,

    z ~ poisson(mu);

is equivalent to

    target += poisson_lpdf(z | mu);

(lpdf = log posterior density function).

So, if you don’t put a prior on something, it implicitly has a uniform prior (i.e., a flat prior).

Error messages

These are important. Pay attention to them, and fix the problems.

Run code in the console. Rstudio often hides useful information.

Parameterization matters

More on this later.

Including overdispersion

How can we include overdispersion?

  1. Counts are Poisson,

  2. with mean that depends on age and exposure,

  3. but effect of exposure depends on genotype.

  4. Actually, counts are overdispersed, so make the means random, and lognormally distributed.

\[\begin{aligned} Z_i &\sim \Poisson(\mu_i) \\ \mu_i &= \exp\left( a_{g_i} + b \times \text{age}_i + c_{g_i} \times \text{exposure}_i \right) \end{aligned}\]

  1. Counts are Poisson,

  2. with mean that depends on age and exposure,

  3. but effect of exposure depends on genotype.

  4. Actually, counts are overdispersed, so the means are random, and lognormally distributed.

\[\begin{aligned} Z_i &\sim \Poisson(\mu_i) \\ \mu_i &= \exp(W_i) \\ W_i &\sim \Normal(y_i, \sigma) \\ y_i &= a_{g_i} + b \times \text{age}_i + c_{g_i} \times \text{exposure}_i \end{aligned}\]

  1. Counts are Poisson,

  2. with mean that depends on age and exposure,

  3. but effect of exposure depends on genotype.

  4. Actually, counts are overdispersed, so the means are random, and lognormally distributed.

\[\begin{aligned} Z_i &\sim \Poisson(\mu_i) \\ \mu_i &\sim \log\Normal(y_i, \sigma) \\ y_i &= a_{g_i} + b \times \text{age}_i + c_{g_i} \times \text{exposure}_i \end{aligned}\]

Your turn: add overdispersion

\[\begin{aligned} Z_i &\sim \Poisson(\mu_i) \\ \mu_i &\sim \log\Normal(y_i, \sigma) \\ y_i &= a_{g_i} + b \times \text{age}_i \\ &\qquad {} + c_{g_i} \times \text{exposure}_i \end{aligned}\]

You can download the data here.

overdispersed_model <- stan_model(model_code="
data {
    int N; // number of data points
    vector[N] age;
    vector[N] exposure;
    int counts[N];
    int genotype[N];
    int ngenotypes;
}
parameters {
    vector[ngenotypes] a; // intercepts
    real b; // slope for age
    vector[ngenotypes] c; // slopes for exposure
    real<lower=0> sigma; // SD on lognormal
    vector[N] mu; // mean of the poissons
}
model {
    vector[N] y; // mean of the lognormals
    y = a[genotype] + b * age + c[genotype] .* exposure;
    mu ~ lognormal(y, sigma);
    counts ~ poisson(mu);
    a ~ normal(0, 100);
    b ~ normal(0, 10);
    c ~ normal(0, 20);
    sigma ~ normal(0, 10);
}")
## Inference for Stan model: lognormal_poisson.
## 3 chains, each with iter=1000; warmup=500; thin=1; 
## post-warmup draws per chain=500, total post-warmup draws=1500.
## 
##             mean se_mean    sd     2.5%      25%      50%      75%
## mu[1]       0.96    0.02  0.72     0.16     0.47     0.75     1.23
## mu[2]       9.10    0.06  2.85     4.51     7.03     8.75    10.88
## mu[3]      26.22    0.10  5.18    17.09    22.44    25.86    29.44
## mu[4]       2.11    0.02  1.16     0.56     1.26     1.89     2.68
## mu[5]      12.39    0.06  3.25     6.83    10.06    12.18    14.32
## mu[6]       3.32    0.03  1.54     1.06     2.25     3.04     4.16
## mu[7]       2.53    0.02  1.31     0.74     1.60     2.26     3.18
## mu[8]       3.76    0.03  1.77     1.20     2.49     3.46     4.68
## mu[9]       0.93    0.01  0.68     0.17     0.46     0.76     1.20
## mu[10]      1.35    0.02  0.84     0.27     0.74     1.15     1.75
## mu[11]      2.56    0.03  1.38     0.73     1.54     2.31     3.31
## mu[12]     10.87    0.06  3.05     5.67     8.74    10.56    12.70
## mu[13]      3.25    0.03  1.57     0.98     2.18     2.96     4.00
## mu[14]     11.57    0.06  3.29     6.21     9.36    11.21    13.48
## mu[15]      0.51    0.01  0.47     0.07     0.20     0.37     0.66
## mu[16]      2.96    0.03  1.56     0.84     1.78     2.64     3.79
## mu[17]      0.86    0.01  0.64     0.16     0.40     0.70     1.11
## mu[18]     67.14    0.14  8.04    52.32    61.60    66.87    72.58
## mu[19]      1.49    0.02  0.94     0.34     0.83     1.27     1.90
## mu[20]      1.74    0.02  1.07     0.43     0.97     1.49     2.21
## mu[21]      2.30    0.03  1.33     0.53     1.33     2.03     2.99
## mu[22]      3.81    0.04  1.81     1.33     2.55     3.46     4.68
## mu[23]      7.40    0.05  2.64     3.13     5.45     7.10     8.97
## mu[24]     28.42    0.11  5.24    19.44    24.81    28.00    31.81
## mu[25]      2.57    0.02  1.32     0.74     1.59     2.32     3.30
## mu[26]      3.23    0.03  1.58     0.98     2.09     2.95     4.11
## mu[27]      0.91    0.01  0.67     0.17     0.46     0.74     1.17
## mu[28]      1.41    0.02  0.94     0.30     0.74     1.18     1.86
## mu[29]      1.69    0.02  1.01     0.37     0.95     1.49     2.19
## mu[30]      2.29    0.02  1.26     0.58     1.34     2.07     3.01
## mu[31]      8.93    0.05  2.91     4.30     6.81     8.55    10.56
## mu[32]     65.07    0.14  8.14    50.57    59.23    64.70    70.35
## mu[33]    105.66    0.19 10.31    86.37    98.51   105.62   112.76
## mu[34]      3.74    0.04  1.72     1.22     2.52     3.45     4.65
## mu[35]     23.71    0.09  4.88    15.12    20.40    23.24    26.69
## mu[36]      3.42    0.03  1.63     1.14     2.22     3.12     4.30
## mu[37]      7.12    0.04  2.40     3.12     5.37     6.84     8.76
## mu[38]      7.39    0.05  2.71     3.17     5.39     7.07     8.91
## mu[39]      2.93    0.03  1.44     0.88     1.88     2.67     3.72
## mu[40]     16.40    0.07  4.22     9.38    13.34    16.02    19.16
## mu[41]      2.11    0.02  1.14     0.56     1.28     1.89     2.66
## mu[42]      9.98    0.06  3.03     4.89     7.84     9.64    11.75
## mu[43]      4.67    0.03  1.92     1.76     3.32     4.37     5.78
## mu[44]     75.26    0.13  8.56    59.67    69.00    75.07    81.19
## mu[45]      1.02    0.01  0.71     0.18     0.52     0.84     1.30
## mu[46]      0.88    0.01  0.62     0.17     0.44     0.72     1.17
## mu[47]      5.96    0.04  2.26     2.44     4.38     5.70     7.13
## mu[48]      1.23    0.02  0.80     0.24     0.67     1.06     1.58
## mu[49]      1.61    0.02  1.04     0.34     0.86     1.38     2.07
## mu[50]      3.82    0.03  1.70     1.30     2.55     3.51     4.86
## mu[51]      3.28    0.03  1.62     1.01     2.14     2.97     4.16
## mu[52]      1.48    0.02  0.93     0.34     0.82     1.27     1.90
## mu[53]    131.28    0.22 11.13   110.32   123.66   131.10   138.17
## mu[54]     17.98    0.07  4.27    10.75    14.95    17.73    20.56
## mu[55]     68.78    0.13  8.06    53.75    63.03    68.55    74.22
## mu[56]      1.34    0.02  0.84     0.30     0.75     1.14     1.71
## mu[57]      2.90    0.03  1.54     0.83     1.78     2.64     3.70
## mu[58]      1.28    0.02  0.80     0.27     0.69     1.10     1.68
## mu[59]      0.62    0.01  0.48     0.10     0.28     0.50     0.82
## mu[60]      6.15    0.05  2.39     2.46     4.43     5.78     7.48
## mu[61]     59.15    0.15  7.69    44.69    53.77    58.71    64.24
## mu[62]      2.21    0.02  1.25     0.56     1.31     1.93     2.81
## mu[63]      1.68    0.02  1.01     0.39     0.92     1.46     2.21
## mu[64]     30.04    0.09  5.22    20.40    26.37    29.73    33.54
## mu[65]      1.66    0.02  1.01     0.40     0.92     1.42     2.19
## mu[66]      1.63    0.02  1.02     0.34     0.91     1.38     2.12
## mu[67]     17.82    0.07  4.03    10.93    14.87    17.52    20.30
## mu[68]      2.04    0.02  1.21     0.53     1.18     1.82     2.61
## mu[69]     19.25    0.07  4.13    11.99    16.42    18.96    21.72
## mu[70]      2.58    0.03  1.45     0.66     1.55     2.26     3.32
## mu[71]      7.78    0.05  2.82     3.50     5.67     7.35     9.58
## mu[72]      0.95    0.01  0.68     0.17     0.45     0.77     1.25
## mu[73]      4.08    0.03  1.77     1.49     2.80     3.77     5.04
## mu[74]      9.08    0.06  2.85     4.48     7.03     8.72    10.90
## mu[75]      9.69    0.05  2.84     4.98     7.72     9.39    11.50
## mu[76]      5.46    0.04  2.09     2.12     3.91     5.17     6.75
## mu[77]     22.56    0.08  4.47    14.71    19.38    22.36    25.53
## mu[78]      2.36    0.03  1.30     0.65     1.36     2.09     3.12
## mu[79]      2.91    0.03  1.50     0.83     1.81     2.63     3.71
## mu[80]     36.38    0.10  6.02    25.65    32.12    36.19    40.32
## mu[81]      2.33    0.02  1.26     0.65     1.41     2.10     2.96
## mu[82]      5.97    0.04  2.25     2.52     4.33     5.66     7.37
## mu[83]      7.37    0.04  2.55     3.39     5.49     7.01     8.93
## mu[84]     24.43    0.09  4.66    16.20    21.14    24.17    27.27
## mu[85]     10.94    0.05  3.32     5.67     8.46    10.61    13.14
## mu[86]      2.10    0.02  1.15     0.55     1.27     1.85     2.66
## mu[87]      0.96    0.02  0.69     0.18     0.47     0.78     1.25
## mu[88]      4.07    0.03  1.74     1.48     2.81     3.80     4.98
## mu[89]      3.12    0.03  1.56     0.97     1.92     2.85     3.93
## mu[90]      2.20    0.02  1.19     0.62     1.33     1.97     2.84
## mu[91]      2.37    0.03  1.23     0.70     1.46     2.15     3.02
## mu[92]      2.21    0.02  1.26     0.58     1.32     1.94     2.84
## mu[93]      5.34    0.04  2.05     2.20     3.84     5.07     6.50
## mu[94]     20.01    0.07  4.42    12.49    16.79    19.66    22.64
## mu[95]      3.24    0.03  1.55     1.05     2.11     2.96     4.03
## mu[96]      9.35    0.05  2.80     4.71     7.34     9.00    10.90
## mu[97]      3.67    0.03  1.70     1.27     2.47     3.37     4.52
## mu[98]      2.21    0.02  1.23     0.59     1.32     1.96     2.80
## mu[99]      1.75    0.02  1.05     0.41     1.00     1.51     2.23
## mu[100]    39.75    0.11  5.87    29.32    35.83    39.37    43.27
## mu[101]     7.32    0.05  2.55     3.14     5.53     7.03     8.76
## mu[102]    26.36    0.10  5.14    17.20    22.90    26.01    29.54
## mu[103]     2.82    0.03  1.48     0.77     1.77     2.51     3.58
## mu[104]     1.97    0.02  1.11     0.52     1.20     1.75     2.50
## mu[105]     1.30    0.02  0.88     0.24     0.68     1.08     1.68
## mu[106]     1.93    0.02  1.12     0.45     1.14     1.72     2.44
## mu[107]     8.81    0.04  2.80     4.15     6.75     8.50    10.72
## mu[108]    16.86    0.07  4.04     9.98    13.95    16.51    19.39
## mu[109]     8.99    0.05  2.79     4.47     7.05     8.66    10.63
## mu[110]     1.96    0.03  1.14     0.50     1.16     1.73     2.46
## mu[111]     2.57    0.03  1.42     0.63     1.58     2.33     3.20
## mu[112]     2.90    0.03  1.48     0.89     1.79     2.64     3.65
## mu[113]    14.08    0.07  3.71     7.99    11.46    13.70    16.28
## mu[114]     7.50    0.04  2.66     3.26     5.58     7.19     9.12
## mu[115]     5.31    0.04  2.04     2.10     3.83     5.06     6.44
## mu[116]     1.79    0.02  1.07     0.39     1.02     1.55     2.29
## mu[117]    14.41    0.07  3.71     8.11    11.70    14.07    16.94
## mu[118]     1.44    0.02  0.98     0.28     0.77     1.21     1.81
## mu[119]     8.21    0.05  2.72     3.78     6.28     8.00     9.72
## mu[120]    20.06    0.08  4.50    12.14    16.95    19.69    22.88
## mu[121]     2.81    0.03  1.36     0.90     1.79     2.56     3.59
## mu[122]    15.18    0.06  3.66     8.91    12.72    14.81    17.30
## mu[123]     2.16    0.02  1.23     0.57     1.25     1.91     2.73
## mu[124]     1.15    0.02  0.80     0.23     0.59     0.94     1.47
## mu[125]     2.17    0.02  1.15     0.59     1.30     1.94     2.82
## mu[126]     3.39    0.03  1.68     1.12     2.17     3.09     4.29
## mu[127]    22.16    0.09  4.67    14.18    18.84    21.64    25.10
## mu[128]     2.06    0.02  1.13     0.53     1.22     1.80     2.63
## mu[129]     5.42    0.04  2.16     2.15     3.80     5.12     6.70
## mu[130]     8.93    0.05  2.66     4.50     7.00     8.69    10.50
## mu[131]     1.68    0.02  1.04     0.38     0.94     1.44     2.18
## mu[132]     6.66    0.05  2.49     2.79     4.85     6.32     8.11
## mu[133]     1.14    0.02  0.80     0.21     0.56     0.94     1.49
## mu[134]    27.17    0.09  5.40    17.96    23.22    26.75    30.74
## mu[135]    13.39    0.06  3.44     7.55    10.90    13.12    15.37
## mu[136]     5.08    0.04  1.93     2.13     3.68     4.80     6.15
## mu[137]     8.30    0.05  2.75     4.04     6.29     7.97    10.05
## mu[138]     9.29    0.05  2.81     4.78     7.23     8.93    11.09
## mu[139]     4.80    0.03  1.94     1.84     3.39     4.54     5.89
## mu[140]     7.76    0.05  2.67     3.47     5.84     7.54     9.36
## mu[141]     2.17    0.02  1.20     0.57     1.28     1.93     2.77
## mu[142]     0.92    0.01  0.67     0.15     0.46     0.76     1.19
## mu[143]    27.86    0.09  5.03    19.07    24.18    27.46    31.03
## mu[144]     2.65    0.03  1.42     0.71     1.61     2.43     3.37
## mu[145]    18.58    0.08  4.08    11.28    15.73    18.27    21.15
## mu[146]     2.27    0.03  1.28     0.58     1.34     2.01     2.91
## mu[147]     2.87    0.03  1.44     0.81     1.82     2.64     3.61
## mu[148]     1.30    0.02  0.82     0.28     0.70     1.13     1.71
## mu[149]     5.89    0.04  2.22     2.36     4.24     5.66     7.21
## mu[150]     5.09    0.04  1.94     2.01     3.71     4.80     6.21
## mu[151]     4.75    0.04  2.05     1.76     3.18     4.46     5.94
## mu[152]     3.81    0.03  1.68     1.36     2.59     3.56     4.70
## mu[153]     2.23    0.03  1.27     0.54     1.31     1.97     2.84
## mu[154]     2.89    0.03  1.45     0.84     1.83     2.62     3.63
## mu[155]     6.73    0.04  2.34     3.02     5.02     6.47     8.09
## mu[156]     0.77    0.01  0.54     0.15     0.38     0.62     1.00
## mu[157]    23.07    0.09  4.71    14.42    19.74    22.77    26.01
## mu[158]    45.53    0.12  7.08    32.53    40.80    45.03    49.83
## mu[159]     0.96    0.02  0.71     0.15     0.49     0.80     1.22
## mu[160]     3.63    0.03  1.72     1.17     2.40     3.32     4.50
## mu[161]    15.99    0.07  3.94     9.19    13.24    15.65    18.47
## mu[162]     2.03    0.02  1.16     0.47     1.17     1.79     2.65
## mu[163]   107.59    0.16 10.63    87.13   100.34   107.25   114.64
## mu[164]     2.53    0.03  1.40     0.63     1.51     2.20     3.27
## mu[165]    11.25    0.05  3.22     5.94     9.01    10.98    13.33
## mu[166]     0.79    0.01  0.55     0.16     0.41     0.66     1.01
## mu[167]    11.81    0.06  3.29     6.35     9.41    11.45    13.69
## mu[168]     9.43    0.05  2.84     4.86     7.26     9.17    11.20
## mu[169]     3.98    0.03  1.82     1.33     2.70     3.67     4.95
## mu[170]     6.89    0.05  2.53     2.95     5.10     6.56     8.36
## mu[171]     2.13    0.02  1.19     0.55     1.28     1.90     2.76
## mu[172]     2.23    0.02  1.24     0.59     1.33     1.99     2.83
## mu[173]    11.31    0.07  3.26     5.87     8.97    10.98    13.38
## mu[174]     3.06    0.03  1.53     0.90     1.95     2.76     3.91
## mu[175]   100.98    0.20 10.15    81.60    94.21   100.45   107.14
## mu[176]     7.50    0.04  2.50     3.48     5.65     7.17     9.09
## mu[177]     8.39    0.05  2.77     3.86     6.41     8.02    10.01
## mu[178]     3.09    0.03  1.54     0.93     1.94     2.81     3.89
## mu[179]     7.83    0.04  2.48     3.72     6.00     7.59     9.41
## mu[180]     2.29    0.02  1.36     0.51     1.31     1.98     2.98
## mu[181]    13.01    0.06  3.44     7.40    10.56    12.73    15.09
## mu[182]     1.33    0.02  0.85     0.28     0.74     1.12     1.71
## mu[183]     1.77    0.02  1.13     0.35     0.98     1.55     2.29
## mu[184]    12.90    0.06  3.56     7.03    10.38    12.51    15.21
## mu[185]     2.27    0.02  1.21     0.63     1.43     2.06     2.86
## mu[186]     5.24    0.04  2.18     1.98     3.63     4.93     6.53
## mu[187]     1.81    0.02  1.05     0.40     1.06     1.58     2.38
## mu[188]     9.24    0.05  2.87     4.36     7.25     8.97    10.91
## mu[189]    27.48    0.09  5.09    18.37    23.84    27.21    30.87
## mu[190]     1.60    0.02  0.98     0.36     0.89     1.37     2.08
## mu[191]     8.02    0.04  2.67     3.78     6.15     7.68     9.56
## mu[192]     6.11    0.04  2.21     2.68     4.47     5.80     7.43
## mu[193]     0.86    0.01  0.65     0.13     0.40     0.69     1.13
## mu[194]     3.82    0.03  1.68     1.25     2.58     3.56     4.81
## mu[195]    10.83    0.05  3.05     5.81     8.54    10.49    12.89
## mu[196]     3.78    0.04  1.77     1.22     2.48     3.48     4.72
## mu[197]     2.19    0.02  1.26     0.53     1.30     1.94     2.79
## mu[198]     6.51    0.04  2.28     2.89     4.85     6.23     7.86
## mu[199]     1.64    0.02  1.00     0.38     0.93     1.41     2.09
## mu[200]     1.05    0.02  0.76     0.18     0.50     0.85     1.43
## mu[201]    17.49    0.07  3.93    10.65    14.72    17.22    19.90
## mu[202]     2.96    0.03  1.51     0.87     1.87     2.69     3.75
## mu[203]     5.02    0.04  2.03     1.96     3.57     4.74     6.21
## mu[204]     1.13    0.02  0.80     0.19     0.55     0.92     1.50
## mu[205]     4.78    0.04  1.96     1.74     3.38     4.45     5.94
## mu[206]     0.70    0.01  0.54     0.10     0.33     0.56     0.93
## mu[207]     2.64    0.03  1.34     0.77     1.65     2.42     3.37
## mu[208]     2.75    0.03  1.41     0.79     1.75     2.49     3.47
## mu[209]     1.71    0.02  1.00     0.41     0.97     1.52     2.22
## mu[210]     4.79    0.04  1.91     2.02     3.36     4.53     5.88
## mu[211]    18.32    0.07  4.03    11.48    15.31    17.96    21.03
## mu[212]     5.38    0.04  2.18     2.12     3.68     5.03     6.72
## mu[213]    27.56    0.10  5.14    18.51    23.91    27.17    30.91
## mu[214]     4.93    0.03  2.04     1.84     3.45     4.61     6.08
## mu[215]     1.72    0.02  1.02     0.38     0.97     1.49     2.24
## mu[216]     0.90    0.02  0.71     0.13     0.41     0.71     1.15
## mu[217]    17.26    0.07  4.18    10.53    14.22    16.84    19.90
## mu[218]    28.34    0.09  5.30    18.63    24.60    27.94    31.77
## mu[219]     1.74    0.02  1.01     0.43     1.01     1.53     2.26
## mu[220]     3.73    0.03  1.73     1.25     2.47     3.44     4.58
## mu[221]     1.92    0.02  1.11     0.47     1.09     1.68     2.47
## mu[222]    46.64    0.11  6.95    34.11    41.93    46.40    51.23
## mu[223]     5.63    0.04  2.20     2.18     4.00     5.36     6.86
## mu[224]     5.15    0.04  2.08     2.07     3.65     4.84     6.36
## mu[225]     5.76    0.03  2.16     2.41     4.13     5.45     7.08
## mu[226]    39.90    0.11  5.92    29.01    35.68    39.72    43.76
## mu[227]     5.04    0.04  2.02     2.02     3.53     4.76     6.21
## mu[228]     3.41    0.03  1.59     1.16     2.20     3.11     4.33
## mu[229]    53.09    0.13  6.99    40.27    48.12    52.71    57.98
## mu[230]     2.04    0.02  1.18     0.51     1.18     1.79     2.61
## mu[231]   103.12    0.17  9.89    84.88    96.30   102.53   109.58
## mu[232]     7.20    0.04  2.56     3.20     5.34     6.88     8.75
## mu[233]    16.05    0.07  3.82     9.60    13.25    15.81    18.55
## mu[234]    79.09    0.17  8.99    62.10    73.08    78.63    84.78
## mu[235]     6.17    0.04  2.30     2.47     4.53     5.92     7.41
## mu[236]     5.53    0.04  2.12     2.28     3.98     5.26     6.68
## mu[237]    12.88    0.06  3.48     7.07    10.29    12.52    15.12
## mu[238]    18.61    0.07  4.22    11.14    15.60    18.39    21.19
## mu[239]     2.66    0.03  1.37     0.83     1.63     2.38     3.36
## mu[240]    74.36    0.14  8.39    58.75    68.69    74.16    79.42
## mu[241]     4.31    0.04  1.88     1.50     2.89     4.01     5.42
## mu[242]     4.38    0.03  1.85     1.45     3.09     4.09     5.41
## mu[243]     2.63    0.03  1.42     0.69     1.61     2.33     3.36
## mu[244]     1.41    0.02  0.94     0.28     0.76     1.20     1.84
## mu[245]    11.23    0.06  3.19     5.76     9.01    10.83    13.14
## mu[246]     6.61    0.05  2.45     2.85     4.85     6.34     8.09
## mu[247]     5.05    0.04  2.05     1.99     3.52     4.66     6.30
## mu[248]    19.47    0.08  4.33    11.96    16.45    19.05    22.05
## mu[249]     1.07    0.02  0.74     0.19     0.54     0.91     1.42
## mu[250]     4.39    0.03  1.91     1.57     3.00     4.07     5.51
## mu[251]     1.59    0.02  1.00     0.34     0.88     1.38     2.05
## mu[252]     8.44    0.05  2.76     4.14     6.43     8.10    10.15
## mu[253]     0.82    0.01  0.60     0.14     0.41     0.67     1.06
## mu[254]    34.13    0.10  6.08    23.13    29.88    33.81    37.82
## mu[255]    16.87    0.06  3.91    10.08    13.97    16.60    19.35
## mu[256]     1.22    0.02  0.84     0.22     0.63     1.00     1.62
## mu[257]     4.46    0.04  1.79     1.78     3.09     4.20     5.58
## mu[258]     8.72    0.05  2.77     4.16     6.81     8.37    10.46
## mu[259]    23.19    0.08  4.82    14.89    19.73    22.85    26.33
## mu[260]    22.33    0.09  4.65    14.27    18.96    22.09    25.33
## mu[261]     4.22    0.03  1.81     1.58     2.85     3.98     5.26
## mu[262]     3.25    0.03  1.58     0.97     2.13     2.97     4.10
## mu[263]     4.73    0.03  2.00     1.67     3.26     4.45     5.86
## mu[264]    27.48    0.09  4.97    18.77    24.15    27.21    30.54
## mu[265]     1.86    0.02  1.11     0.41     1.04     1.64     2.39
## mu[266]     5.43    0.04  2.08     2.15     3.94     5.08     6.55
## mu[267]    13.63    0.07  3.70     7.11    11.07    13.31    15.69
## mu[268]     7.98    0.05  2.67     3.68     6.09     7.76     9.54
## mu[269]     1.32    0.02  0.87     0.27     0.69     1.11     1.72
## mu[270]     1.08    0.02  0.75     0.21     0.56     0.89     1.39
## mu[271]     3.74    0.03  1.64     1.33     2.55     3.47     4.64
## mu[272]    10.71    0.06  3.02     5.75     8.49    10.51    12.44
## mu[273]     3.14    0.03  1.60     0.93     2.01     2.85     3.91
## mu[274]     0.83    0.01  0.59     0.16     0.42     0.66     1.10
## mu[275]     2.39    0.03  1.29     0.63     1.45     2.11     3.05
## mu[276]     0.88    0.01  0.62     0.16     0.44     0.72     1.16
## mu[277]     4.37    0.03  1.91     1.58     2.94     4.11     5.41
## mu[278]     6.96    0.05  2.42     3.16     5.17     6.63     8.39
## mu[279]    15.05    0.06  3.67     8.53    12.46    14.82    17.25
## mu[280]     1.07    0.02  0.79     0.17     0.47     0.86     1.46
## mu[281]    76.29    0.14  8.24    61.72    70.34    76.00    81.67
## mu[282]     2.19    0.02  1.23     0.54     1.27     1.97     2.85
## mu[283]     8.57    0.05  2.84     4.16     6.53     8.12    10.35
## mu[284]     9.68    0.05  2.94     4.86     7.51     9.37    11.55
## mu[285]     1.48    0.02  0.93     0.35     0.83     1.27     1.92
## mu[286]     8.66    0.05  2.84     4.15     6.75     8.31    10.32
## mu[287]     2.21    0.02  1.17     0.60     1.34     2.00     2.85
## mu[288]     4.36    0.03  1.80     1.67     3.08     4.13     5.34
## mu[289]     0.92    0.02  0.70     0.15     0.42     0.73     1.21
## mu[290]     2.85    0.02  1.44     0.78     1.79     2.59     3.66
## mu[291]   131.27    0.18 11.43   109.36   123.85   130.86   138.78
## mu[292]    15.98    0.06  3.94     9.02    13.14    15.64    18.56
## mu[293]     2.28    0.02  1.26     0.57     1.34     2.05     2.90
## mu[294]     4.30    0.03  1.80     1.57     2.98     4.06     5.28
## mu[295]     1.30    0.02  0.86     0.26     0.69     1.10     1.66
## mu[296]    22.09    0.09  4.68    14.09    18.90    21.81    25.04
## mu[297]     2.57    0.02  1.30     0.81     1.65     2.34     3.22
## mu[298]     6.48    0.04  2.29     2.88     4.83     6.23     7.75
## mu[299]    10.75    0.06  3.28     5.26     8.41    10.48    12.61
## mu[300]     6.22    0.05  2.28     2.61     4.53     5.96     7.59
## mu[301]     2.08    0.02  1.14     0.54     1.29     1.86     2.60
## mu[302]     6.01    0.04  2.31     2.43     4.34     5.67     7.33
## mu[303]     3.10    0.03  1.55     0.95     1.99     2.78     4.03
## mu[304]     9.05    0.05  2.96     4.27     6.93     8.70    10.78
## mu[305]     2.21    0.03  1.24     0.57     1.29     1.96     2.86
## mu[306]     2.47    0.02  1.31     0.65     1.50     2.23     3.20
## mu[307]    17.79    0.07  3.98    10.94    15.01    17.47    20.12
## mu[308]     1.46    0.02  0.96     0.29     0.76     1.21     1.92
## mu[309]     4.28    0.04  1.86     1.58     2.89     3.98     5.32
## mu[310]     3.20    0.03  1.44     1.06     2.19     2.99     4.01
## mu[311]     4.11    0.03  1.76     1.49     2.83     3.83     5.11
## mu[312]     4.67    0.03  1.89     1.81     3.27     4.42     5.77
## mu[313]    13.21    0.06  3.52     7.36    10.69    12.89    15.35
## mu[314]     1.53    0.02  1.00     0.31     0.82     1.28     1.99
## mu[315]     1.64    0.02  0.98     0.36     0.91     1.41     2.15
## mu[316]     0.74    0.01  0.54     0.13     0.35     0.59     0.98
## mu[317]     2.76    0.03  1.48     0.74     1.69     2.47     3.47
## mu[318]     3.28    0.03  1.56     1.02     2.18     3.00     4.14
## mu[319]    39.54    0.11  5.90    28.61    35.34    39.11    43.63
## mu[320]    23.65    0.08  4.33    15.51    20.76    23.47    26.36
## mu[321]     4.54    0.04  1.94     1.67     3.14     4.26     5.71
## mu[322]     1.26    0.02  0.85     0.24     0.65     1.03     1.67
## mu[323]    34.18    0.09  5.83    23.42    30.27    33.81    37.55
## mu[324]     4.64    0.03  1.91     1.73     3.26     4.34     5.75
## mu[325]    10.42    0.05  3.15     5.11     8.12    10.20    12.37
## mu[326]     2.52    0.03  1.37     0.70     1.52     2.23     3.24
## mu[327]     5.64    0.04  2.12     2.32     4.13     5.39     6.90
## mu[328]     1.95    0.02  1.15     0.44     1.14     1.71     2.50
## mu[329]    26.77    0.08  5.04    17.76    23.17    26.49    30.01
## mu[330]     3.28    0.03  1.58     1.04     2.14     3.02     4.09
## mu[331]     2.52    0.02  1.32     0.71     1.55     2.25     3.24
## mu[332]     4.29    0.03  1.80     1.58     3.02     4.03     5.29
## mu[333]    21.07    0.07  4.34    13.24    18.05    20.76    23.81
## mu[334]    14.28    0.07  3.55     8.16    11.73    13.99    16.58
## mu[335]     2.45    0.02  1.28     0.68     1.54     2.22     3.08
## mu[336]    26.28    0.10  4.77    17.71    22.85    26.04    29.38
## mu[337]    30.09    0.10  5.44    20.59    26.27    29.79    33.72
## mu[338]    27.23    0.08  4.87    18.62    23.68    26.96    30.33
## mu[339]    12.39    0.05  3.19     6.83    10.22    12.12    14.34
## mu[340]     3.88    0.03  1.74     1.28     2.60     3.60     4.88
## mu[341]     1.44    0.02  0.92     0.31     0.79     1.21     1.89
## mu[342]     2.92    0.03  1.51     0.91     1.79     2.64     3.78
## mu[343]     2.23    0.02  1.23     0.60     1.34     1.94     2.82
## mu[344]     1.36    0.02  0.85     0.30     0.77     1.16     1.74
## mu[345]     0.83    0.01  0.65     0.12     0.38     0.65     1.08
## mu[346]     1.07    0.01  0.76     0.18     0.51     0.85     1.42
## mu[347]     6.81    0.04  2.41     2.98     5.15     6.50     8.18
## mu[348]    17.86    0.07  3.88    11.11    15.21    17.66    20.26
## mu[349]    10.98    0.05  3.20     5.79     8.58    10.57    12.87
## mu[350]     3.78    0.03  1.72     1.20     2.56     3.54     4.63
## mu[351]    18.33    0.08  4.31    10.62    15.32    18.05    21.01
## mu[352]     9.50    0.05  2.94     4.82     7.33     9.16    11.30
## mu[353]     3.08    0.03  1.52     0.95     2.01     2.77     3.85
## mu[354]   172.93    0.23 13.84   147.04   163.51   172.50   181.90
## mu[355]     3.15    0.03  1.66     0.89     1.93     2.79     4.08
## mu[356]     2.04    0.03  1.19     0.52     1.16     1.76     2.64
## mu[357]     5.71    0.04  2.20     2.24     4.12     5.44     6.96
## mu[358]    75.75    0.14  8.83    59.21    69.61    75.47    81.32
## mu[359]     4.15    0.03  1.88     1.42     2.78     3.83     5.16
## mu[360]     4.02    0.03  1.75     1.37     2.75     3.75     5.01
## mu[361]     0.57    0.01  0.45     0.07     0.26     0.44     0.74
## mu[362]    29.14    0.09  5.28    19.37    25.57    28.78    32.24
## mu[363]     8.26    0.05  2.54     4.05     6.45     7.98     9.72
## mu[364]     1.40    0.02  0.91     0.28     0.78     1.19     1.79
## mu[365]     9.13    0.05  2.88     4.60     6.98     8.79    10.91
## mu[366]     8.17    0.05  2.76     3.79     6.04     7.91     9.89
## mu[367]    16.01    0.08  3.93     9.26    13.29    15.65    18.33
## mu[368]     1.55    0.02  0.97     0.31     0.85     1.35     1.99
## mu[369]     8.96    0.05  2.90     4.37     6.85     8.58    10.72
## mu[370]    21.45    0.09  4.44    13.68    18.35    21.12    24.11
## mu[371]     3.37    0.03  1.58     1.06     2.22     3.10     4.24
## mu[372]    12.78    0.06  3.31     7.15    10.45    12.54    14.71
## mu[373]     9.36    0.05  2.88     4.68     7.19     9.06    11.23
## mu[374]     1.58    0.02  0.95     0.40     0.89     1.37     2.07
## mu[375]     5.01    0.04  2.02     1.88     3.60     4.71     6.17
## mu[376]    11.92    0.06  3.37     6.30     9.57    11.63    13.90
## mu[377]     6.95    0.04  2.56     2.93     5.15     6.63     8.38
## mu[378]     9.35    0.05  2.91     4.60     7.27     9.04    11.06
## mu[379]    21.38    0.07  4.45    13.30    18.30    21.05    24.20
## mu[380]     4.53    0.03  1.89     1.68     3.19     4.22     5.57
## mu[381]     1.74    0.02  1.05     0.39     0.96     1.49     2.27
## mu[382]     1.92    0.03  1.16     0.45     1.08     1.65     2.45
## mu[383]     1.17    0.02  0.82     0.23     0.58     0.98     1.50
## mu[384]     2.41    0.02  1.23     0.71     1.54     2.21     2.97
## mu[385]     9.87    0.05  3.02     4.97     7.81     9.54    11.64
## mu[386]     1.00    0.02  0.73     0.17     0.49     0.80     1.32
## mu[387]     2.04    0.02  1.14     0.48     1.24     1.81     2.61
## mu[388]     6.49    0.04  2.34     2.88     4.86     6.17     7.79
## mu[389]     9.47    0.05  2.72     4.84     7.54     9.19    11.20
## mu[390]     3.28    0.03  1.64     0.96     2.11     2.97     4.10
## mu[391]     2.06    0.02  1.13     0.56     1.28     1.87     2.62
## mu[392]     4.63    0.03  1.83     1.74     3.32     4.38     5.72
## mu[393]    21.01    0.08  4.50    13.16    17.90    20.73    23.83
## mu[394]     1.60    0.02  0.94     0.38     0.90     1.39     2.09
## mu[395]    11.39    0.05  3.15     6.15     9.01    11.15    13.45
## mu[396]     5.40    0.04  1.99     2.27     3.98     5.12     6.55
## mu[397]     1.25    0.02  0.81     0.26     0.69     1.04     1.59
## mu[398]    86.39    0.15  9.01    69.43    80.02    86.10    92.52
## mu[399]     2.33    0.02  1.26     0.59     1.41     2.09     3.00
## mu[400]    13.64    0.06  3.60     7.52    11.08    13.35    15.84
## mu[401]     4.89    0.04  1.98     1.83     3.42     4.64     6.03
## mu[402]    13.22    0.06  3.44     7.42    10.90    12.86    15.31
## mu[403]     1.21    0.02  0.84     0.23     0.62     1.00     1.58
## mu[404]    15.48    0.07  3.83     9.09    12.65    15.12    17.97
## mu[405]    40.40    0.09  5.92    29.74    36.52    40.08    44.11
## mu[406]     5.30    0.04  2.09     2.07     3.75     5.02     6.54
## mu[407]     1.47    0.02  0.91     0.31     0.83     1.25     1.90
## mu[408]    56.33    0.13  7.70    42.76    51.07    56.04    61.37
## mu[409]     7.13    0.04  2.48     3.42     5.31     6.85     8.60
## mu[410]     4.78    0.04  1.94     1.90     3.30     4.50     5.93
## mu[411]     6.53    0.05  2.40     2.80     4.82     6.24     7.77
## mu[412]     6.35    0.04  2.20     2.71     4.77     6.13     7.68
## mu[413]     1.85    0.02  1.14     0.41     1.01     1.60     2.42
## mu[414]     1.07    0.02  0.77     0.18     0.52     0.88     1.38
## mu[415]     4.49    0.04  1.97     1.57     3.07     4.20     5.62
## mu[416]     5.18    0.03  2.04     1.95     3.73     4.92     6.34
## mu[417]     3.40    0.03  1.67     1.05     2.13     3.06     4.40
## mu[418]     9.91    0.05  3.01     4.80     7.77     9.65    11.70
## mu[419]     3.20    0.03  1.62     0.91     2.08     2.89     4.02
## mu[420]    27.13    0.09  5.11    18.09    23.53    26.84    30.44
## mu[421]     7.03    0.05  2.47     3.13     5.19     6.71     8.48
## mu[422]    11.08    0.06  3.14     6.01     8.78    10.69    13.12
## mu[423]     2.08    0.02  1.17     0.53     1.23     1.85     2.63
## mu[424]     5.66    0.04  2.16     2.21     4.05     5.38     6.90
## mu[425]    10.64    0.05  3.09     5.70     8.35    10.29    12.72
## mu[426]    15.48    0.08  3.63     9.21    12.97    15.22    17.70
## mu[427]     1.08    0.02  0.76     0.18     0.54     0.89     1.42
## mu[428]     5.97    0.04  2.40     2.29     4.21     5.60     7.42
## mu[429]     1.71    0.02  1.04     0.38     0.93     1.48     2.25
## mu[430]     1.96    0.02  1.11     0.46     1.16     1.74     2.54
## mu[431]     2.94    0.03  1.50     0.91     1.83     2.70     3.66
## mu[432]     8.94    0.05  2.81     4.41     6.84     8.67    10.72
## mu[433]    16.93    0.08  4.39     9.43    13.92    16.57    19.43
## mu[434]     3.35    0.03  1.63     1.02     2.13     3.04     4.29
## mu[435]     6.64    0.04  2.35     2.89     4.95     6.34     8.00
## mu[436]     6.35    0.05  2.36     2.51     4.69     6.15     7.66
## mu[437]     6.21    0.05  2.24     2.75     4.57     5.96     7.47
## mu[438]     1.78    0.02  1.08     0.39     1.01     1.53     2.33
## mu[439]     6.09    0.04  2.26     2.59     4.52     5.77     7.38
## mu[440]    18.78    0.08  4.22    11.75    15.75    18.48    21.47
## mu[441]     4.26    0.03  1.83     1.49     2.90     4.01     5.28
## mu[442]     2.32    0.03  1.24     0.64     1.42     2.09     2.98
## mu[443]    81.23    0.15  8.67    65.43    75.08    81.07    87.03
## mu[444]     4.24    0.03  1.86     1.46     2.90     3.99     5.21
## mu[445]     3.35    0.03  1.66     1.04     2.13     3.08     4.17
## mu[446]     3.02    0.03  1.48     0.84     1.98     2.79     3.72
## mu[447]     3.36    0.03  1.68     1.04     2.11     3.03     4.27
## mu[448]     3.45    0.03  1.59     1.20     2.31     3.14     4.39
## mu[449]    13.02    0.07  3.38     7.55    10.49    12.76    15.15
## mu[450]     1.48    0.02  0.96     0.30     0.77     1.25     1.97
## mu[451]     3.65    0.03  1.69     1.19     2.40     3.39     4.64
## mu[452]     2.54    0.03  1.36     0.73     1.53     2.28     3.24
## mu[453]     1.27    0.02  0.85     0.24     0.66     1.04     1.72
## mu[454]     1.26    0.02  0.85     0.25     0.63     1.04     1.66
## mu[455]     0.83    0.02  0.67     0.12     0.38     0.63     1.09
## mu[456]     5.00    0.04  2.05     1.90     3.48     4.73     6.21
## mu[457]     1.48    0.02  0.87     0.38     0.84     1.29     1.90
## mu[458]     4.98    0.04  2.04     1.88     3.49     4.70     6.07
## mu[459]    31.96    0.12  5.64    22.05    27.92    31.61    35.71
## mu[460]     2.76    0.02  1.38     0.75     1.80     2.53     3.50
## mu[461]     5.77    0.04  2.28     2.24     4.16     5.44     6.98
## mu[462]     5.51    0.04  2.09     2.24     4.00     5.23     6.68
## mu[463]     1.09    0.01  0.73     0.20     0.56     0.93     1.39
## mu[464]     1.40    0.02  0.84     0.30     0.79     1.23     1.80
## mu[465]     4.42    0.03  1.89     1.68     3.06     4.13     5.45
## mu[466]    15.87    0.07  3.93     9.01    13.04    15.54    18.44
## mu[467]     2.37    0.02  1.23     0.67     1.44     2.15     3.06
## mu[468]     1.25    0.02  0.84     0.24     0.66     1.04     1.66
## mu[469]     3.39    0.03  1.53     1.17     2.27     3.14     4.17
## mu[470]    29.17    0.08  4.91    20.43    25.81    28.77    32.27
## mu[471]     1.55    0.02  0.92     0.36     0.87     1.35     2.01
## mu[472]    19.06    0.08  4.32    11.86    15.98    18.78    21.76
## mu[473]     3.37    0.03  1.53     1.12     2.26     3.14     4.23
## mu[474]     8.25    0.05  2.74     3.91     6.33     7.87     9.80
## mu[475]    17.28    0.07  3.92    10.53    14.50    16.97    19.78
## mu[476]    16.99    0.06  3.87    10.13    14.27    16.76    19.49
## mu[477]     8.81    0.05  2.79     4.27     6.84     8.41    10.47
## mu[478]    20.02    0.09  4.48    12.28    16.86    19.78    22.73
## mu[479]    16.28    0.08  4.01     9.47    13.43    15.93    18.87
## mu[480]    12.78    0.06  3.39     7.07    10.34    12.47    14.84
## mu[481]     2.58    0.02  1.37     0.73     1.53     2.32     3.37
## mu[482]     7.45    0.05  2.61     3.28     5.54     7.19     9.07
## mu[483]     4.68    0.04  1.92     1.74     3.36     4.36     5.77
## mu[484]     7.69    0.05  2.69     3.45     5.71     7.32     9.32
## mu[485]     2.41    0.02  1.25     0.67     1.46     2.18     3.10
## mu[486]     6.30    0.04  2.27     2.76     4.61     5.96     7.79
## mu[487]    92.48    0.18  9.41    75.12    85.99    92.34    98.24
## mu[488]    14.85    0.07  3.79     8.47    12.16    14.49    17.12
## mu[489]     1.03    0.02  0.74     0.19     0.51     0.84     1.32
## mu[490]     3.76    0.03  1.65     1.24     2.53     3.52     4.80
## mu[491]    64.02    0.16  7.74    49.64    58.93    63.60    68.81
## mu[492]     7.19    0.05  2.57     3.14     5.37     6.90     8.71
## mu[493]     1.44    0.02  0.91     0.29     0.77     1.21     1.88
## mu[494]     5.98    0.04  2.24     2.59     4.30     5.67     7.34
## mu[495]     2.35    0.03  1.27     0.58     1.48     2.12     2.98
## mu[496]     2.60    0.03  1.47     0.69     1.53     2.33     3.26
## mu[497]    20.04    0.08  4.27    12.64    17.04    19.72    22.67
## mu[498]   183.63    0.23 13.38   158.40   174.53   183.46   192.32
## mu[499]     4.97    0.04  1.99     1.89     3.55     4.70     6.01
## mu[500]     3.45    0.03  1.68     1.08     2.22     3.14     4.37
## a[1]        1.67    0.00  0.07     1.53     1.63     1.67     1.72
## a[2]        1.43    0.00  0.07     1.28     1.38     1.43     1.47
## b           0.87    0.00  0.05     0.77     0.84     0.87     0.90
## c[1]        0.27    0.00  0.06     0.14     0.22     0.26     0.31
## c[2]       -0.19    0.00  0.08    -0.34    -0.24    -0.18    -0.13
## sigma       0.95    0.00  0.04     0.87     0.92     0.95     0.98
## lp__    12747.44    0.87 18.07 12711.84 12734.64 12748.34 12760.16
##            97.5% n_eff Rhat
## mu[1]       2.96  2009 1.00
## mu[2]      15.39  2380 1.00
## mu[3]      36.91  2842 1.00
## mu[4]       4.76  2703 1.00
## mu[5]      19.59  2661 1.00
## mu[6]       6.89  3424 1.00
## mu[7]       5.72  3525 1.00
## mu[8]       7.91  3754 1.00
## mu[9]       2.70  2234 1.00
## mu[10]      3.38  2530 1.00
## mu[11]      6.01  2947 1.00
## mu[12]     17.74  2367 1.00
## mu[13]      7.16  2422 1.00
## mu[14]     18.93  2921 1.00
## mu[15]      1.69  1803 1.00
## mu[16]      6.71  2167 1.00
## mu[17]      2.49  1943 1.00
## mu[18]     83.27  3413 1.00
## mu[19]      3.90  2225 1.00
## mu[20]      4.37  3731 1.00
## mu[21]      5.57  2315 1.00
## mu[22]      8.11  2213 1.00
## mu[23]     13.73  3153 1.00
## mu[24]     39.00  2168 1.00
## mu[25]      5.75  3549 1.00
## mu[26]      7.05  3036 1.00
## mu[27]      2.72  2406 1.00
## mu[28]      3.73  2689 1.00
## mu[29]      4.14  2188 1.00
## mu[30]      5.30  3609 1.00
## mu[31]     15.90  2991 1.00
## mu[32]     81.49  3433 1.00
## mu[33]    126.87  2990 1.00
## mu[34]      7.93  2361 1.00
## mu[35]     34.72  2798 1.00
## mu[36]      7.38  3863 1.00
## mu[37]     12.49  3497 1.00
## mu[38]     13.38  2784 1.00
## mu[39]      6.54  2795 1.00
## mu[40]     25.75  3469 1.00
## mu[41]      4.88  3000 1.00
## mu[42]     17.11  2434 1.00
## mu[43]      9.15  3714 1.00
## mu[44]     92.39  4166 1.00
## mu[45]      2.89  2345 1.00
## mu[46]      2.43  2650 1.00
## mu[47]     11.28  2857 1.00
## mu[48]      3.20  2260 1.00
## mu[49]      4.25  2852 1.00
## mu[50]      7.82  2906 1.00
## mu[51]      7.12  3287 1.00
## mu[52]      3.82  2448 1.00
## mu[53]    153.18  2526 1.00
## mu[54]     27.37  3519 1.00
## mu[55]     85.19  3790 1.00
## mu[56]      3.37  2347 1.00
## mu[57]      6.58  2483 1.00
## mu[58]      3.38  2792 1.00
## mu[59]      1.86  2779 1.00
## mu[60]     11.60  2625 1.00
## mu[61]     75.18  2730 1.00
## mu[62]      5.31  2602 1.00
## mu[63]      4.20  2882 1.00
## mu[64]     40.68  3728 1.00
## mu[65]      4.11  3145 1.00
## mu[66]      4.36  2656 1.00
## mu[67]     26.40  3755 1.00
## mu[68]      4.99  2525 1.00
## mu[69]     28.49  3191 1.00
## mu[70]      6.38  2747 1.00
## mu[71]     14.23  3445 1.00
## mu[72]      2.76  2280 1.00
## mu[73]      8.32  2590 1.00
## mu[74]     15.70  2325 1.00
## mu[75]     16.08  3485 1.00
## mu[76]     10.06  2709 1.00
## mu[77]     31.87  3375 1.00
## mu[78]      5.44  2670 1.00
## mu[79]      6.42  2632 1.00
## mu[80]     48.39  3910 1.00
## mu[81]      5.36  2825 1.00
## mu[82]     11.03  3463 1.00
## mu[83]     13.40  3216 1.00
## mu[84]     34.41  2682 1.00
## mu[85]     18.26  4602 1.00
## mu[86]      5.23  2505 1.00
## mu[87]      2.85  1814 1.00
## mu[88]      8.16  4026 1.00
## mu[89]      6.87  2809 1.00
## mu[90]      5.00  2575 1.00
## mu[91]      5.48  2383 1.00
## mu[92]      5.25  2747 1.00
## mu[93]      9.97  3371 1.00
## mu[94]     29.70  3500 1.00
## mu[95]      6.89  2950 1.00
## mu[96]     15.91  2815 1.00
## mu[97]      7.87  2840 1.00
## mu[98]      5.33  2530 1.00
## mu[99]      4.36  3296 1.00
## mu[100]    51.71  2960 1.00
## mu[101]    13.22  2719 1.00
## mu[102]    37.46  2842 1.00
## mu[103]     6.33  3176 1.00
## mu[104]     4.76  2437 1.00
## mu[105]     3.51  2396 1.00
## mu[106]     4.86  2659 1.00
## mu[107]    15.10  4274 1.00
## mu[108]    25.67  3294 1.00
## mu[109]    15.42  3222 1.00
## mu[110]     4.70  1917 1.00
## mu[111]     6.01  2423 1.00
## mu[112]     6.47  2445 1.00
## mu[113]    22.56  2857 1.00
## mu[114]    13.15  3775 1.00
## mu[115]    10.02  2888 1.00
## mu[116]     4.43  3035 1.00
## mu[117]    22.33  2604 1.00
## mu[118]     4.05  2351 1.00
## mu[119]    14.44  3200 1.00
## mu[120]    29.96  3414 1.00
## mu[121]     5.85  2886 1.00
## mu[122]    23.21  3924 1.00
## mu[123]     5.16  3008 1.00
## mu[124]     3.27  2183 1.00
## mu[125]     4.80  3381 1.00
## mu[126]     7.35  2453 1.00
## mu[127]    32.33  2933 1.00
## mu[128]     4.74  2622 1.00
## mu[129]    10.31  3401 1.00
## mu[130]    14.79  3251 1.00
## mu[131]     4.34  2704 1.00
## mu[132]    12.74  3055 1.00
## mu[133]     3.18  2558 1.00
## mu[134]    38.62  3874 1.00
## mu[135]    21.42  3236 1.00
## mu[136]     9.49  2964 1.00
## mu[137]    14.34  3662 1.00
## mu[138]    15.36  3565 1.00
## mu[139]     9.03  3641 1.00
## mu[140]    13.88  2601 1.00
## mu[141]     5.06  3218 1.00
## mu[142]     2.70  2427 1.00
## mu[143]    38.91  3194 1.00
## mu[144]     6.33  2327 1.00
## mu[145]    27.31  2552 1.00
## mu[146]     5.63  2518 1.00
## mu[147]     6.08  3174 1.00
## mu[148]     3.35  2696 1.00
## mu[149]    10.91  2510 1.00
## mu[150]     9.75  2324 1.00
## mu[151]     9.48  2226 1.00
## mu[152]     7.70  3328 1.00
## mu[153]     5.46  2523 1.00
## mu[154]     6.68  2900 1.00
## mu[155]    11.99  3196 1.00
## mu[156]     2.30  2264 1.00
## mu[157]    32.99  2919 1.00
## mu[158]    60.40  3669 1.00
## mu[159]     2.84  2238 1.00
## mu[160]     7.65  3119 1.00
## mu[161]    24.83  3283 1.00
## mu[162]     4.70  2869 1.00
## mu[163]   128.49  4274 1.00
## mu[164]     5.84  2677 1.00
## mu[165]    18.20  4096 1.00
## mu[166]     2.21  2013 1.00
## mu[167]    19.36  3353 1.00
## mu[168]    15.73  2886 1.00
## mu[169]     8.37  3911 1.00
## mu[170]    12.64  2853 1.00
## mu[171]     5.02  2677 1.00
## mu[172]     5.27  2541 1.00
## mu[173]    18.39  2112 1.00
## mu[174]     6.71  3648 1.00
## mu[175]   123.17  2526 1.00
## mu[176]    13.29  3563 1.00
## mu[177]    14.73  3158 1.00
## mu[178]     6.83  2587 1.00
## mu[179]    13.29  3160 1.00
## mu[180]     5.54  3242 1.00
## mu[181]    20.89  3569 1.00
## mu[182]     3.63  1735 1.00
## mu[183]     4.52  2061 1.00
## mu[184]    20.52  3057 1.00
## mu[185]     5.39  2958 1.00
## mu[186]    10.19  2434 1.00
## mu[187]     4.34  2610 1.00
## mu[188]    15.72  3140 1.00
## mu[189]    38.07  3318 1.00
## mu[190]     4.18  3393 1.00
## mu[191]    14.11  3551 1.00
## mu[192]    11.30  3796 1.00
## mu[193]     2.52  1952 1.00
## mu[194]     7.79  2453 1.00
## mu[195]    17.37  3271 1.00
## mu[196]     8.10  2211 1.00
## mu[197]     5.31  2606 1.00
## mu[198]    11.61  2896 1.00
## mu[199]     4.28  2329 1.00
## mu[200]     2.96  2094 1.00
## mu[201]    26.00  2900 1.00
## mu[202]     6.75  2913 1.00
## mu[203]     9.73  3278 1.00
## mu[204]     3.13  2077 1.00
## mu[205]     9.30  2392 1.00
## mu[206]     2.16  2669 1.00
## mu[207]     5.72  2754 1.00
## mu[208]     6.12  2929 1.00
## mu[209]     4.15  2719 1.00
## mu[210]     9.36  2334 1.00
## mu[211]    26.59  3763 1.00
## mu[212]    10.51  2602 1.00
## mu[213]    38.63  2666 1.00
## mu[214]     9.65  3489 1.00
## mu[215]     4.31  2178 1.00
## mu[216]     2.84  2233 1.00
## mu[217]    26.37  3686 1.00
## mu[218]    39.61  3154 1.00
## mu[219]     4.02  2785 1.00
## mu[220]     7.98  2609 1.00
## mu[221]     4.69  3221 1.00
## mu[222]    60.93  4082 1.00
## mu[223]    10.83  3000 1.00
## mu[224]     9.74  3014 1.00
## mu[225]    10.52  4205 1.00
## mu[226]    52.17  2912 1.00
## mu[227]     9.74  2993 1.00
## mu[228]     7.19  3532 1.00
## mu[229]    67.11  3056 1.00
## mu[230]     5.01  2985 1.00
## mu[231]   123.48  3368 1.00
## mu[232]    13.02  3344 1.00
## mu[233]    24.15  2987 1.00
## mu[234]    97.24  2965 1.00
## mu[235]    11.71  2902 1.00
## mu[236]    10.50  2497 1.00
## mu[237]    20.40  3630 1.00
## mu[238]    27.63  3658 1.00
## mu[239]     6.01  2841 1.00
## mu[240]    91.54  3353 1.00
## mu[241]     8.73  2728 1.00
## mu[242]     8.76  3165 1.00
## mu[243]     6.22  2056 1.00
## mu[244]     3.74  2387 1.00
## mu[245]    18.50  3281 1.00
## mu[246]    11.99  2404 1.00
## mu[247]     9.87  3254 1.00
## mu[248]    28.97  3091 1.00
## mu[249]     2.95  1933 1.00
## mu[250]     8.56  3319 1.00
## mu[251]     4.09  2478 1.00
## mu[252]    14.80  3183 1.00
## mu[253]     2.37  1935 1.00
## mu[254]    46.58  3671 1.00
## mu[255]    25.34  3793 1.00
## mu[256]     3.39  2508 1.00
## mu[257]     8.44  2473 1.00
## mu[258]    15.00  3154 1.00
## mu[259]    33.21  3265 1.00
## mu[260]    32.21  2983 1.00
## mu[261]     8.42  3947 1.00
## mu[262]     7.18  2239 1.00
## mu[263]     9.39  3383 1.00
## mu[264]    38.07  3346 1.00
## mu[265]     4.68  2066 1.00
## mu[266]    10.47  2512 1.00
## mu[267]    21.98  2982 1.00
## mu[268]    14.09  3423 1.00
## mu[269]     3.68  2521 1.00
## mu[270]     3.09  2408 1.00
## mu[271]     7.70  3096 1.00
## mu[272]    17.40  2375 1.00
## mu[273]     7.19  3301 1.00
## mu[274]     2.24  2508 1.00
## mu[275]     5.54  2495 1.00
## mu[276]     2.49  2879 1.00
## mu[277]     8.78  4507 1.00
## mu[278]    12.47  2385 1.00
## mu[279]    22.66  3201 1.00
## mu[280]     3.07  2197 1.00
## mu[281]    93.33  3522 1.00
## mu[282]     5.13  2752 1.00
## mu[283]    14.87  2704 1.00
## mu[284]    16.03  3706 1.00
## mu[285]     3.65  3054 1.00
## mu[286]    15.08  2792 1.00
## mu[287]     5.07  2536 1.00
## mu[288]     8.64  3175 1.00
## mu[289]     2.63  2054 1.00
## mu[290]     6.35  3467 1.00
## mu[291]   153.91  4009 1.00
## mu[292]    24.30  4533 1.00
## mu[293]     5.56  2702 1.00
## mu[294]     8.34  3178 1.00
## mu[295]     3.68  2115 1.00
## mu[296]    32.22  2691 1.00
## mu[297]     5.75  2710 1.00
## mu[298]    11.88  3573 1.00
## mu[299]    18.31  3207 1.00
## mu[300]    11.21  2515 1.00
## mu[301]     4.89  2672 1.00
## mu[302]    11.27  2762 1.00
## mu[303]     6.76  3327 1.00
## mu[304]    15.67  3008 1.00
## mu[305]     5.27  2253 1.00
## mu[306]     5.49  3324 1.00
## mu[307]    27.00  2964 1.00
## mu[308]     3.80  1952 1.00
## mu[309]     8.63  2791 1.00
## mu[310]     6.74  3062 1.00
## mu[311]     8.22  2675 1.00
## mu[312]     9.13  3798 1.00
## mu[313]    21.04  3656 1.00
## mu[314]     4.01  2231 1.00
## mu[315]     3.88  2319 1.00
## mu[316]     2.19  2244 1.00
## mu[317]     6.39  2823 1.00
## mu[318]     6.99  2753 1.00
## mu[319]    51.60  3023 1.00
## mu[320]    33.09  3252 1.00
## mu[321]     9.01  2716 1.00
## mu[322]     3.42  1796 1.00
## mu[323]    46.82  4007 1.00
## mu[324]     9.25  3125 1.00
## mu[325]    17.83  3479 1.00
## mu[326]     5.95  2369 1.00
## mu[327]    10.23  3467 1.00
## mu[328]     4.96  3266 1.00
## mu[329]    37.93  3927 1.00
## mu[330]     7.14  2424 1.00
## mu[331]     5.78  2965 1.00
## mu[332]     8.66  3241 1.00
## mu[333]    30.26  3735 1.00
## mu[334]    21.55  2543 1.00
## mu[335]     5.68  2819 1.00
## mu[336]    36.44  2339 1.00
## mu[337]    41.35  2968 1.00
## mu[338]    37.34  4016 1.00
## mu[339]    19.51  4107 1.00
## mu[340]     7.65  3370 1.00
## mu[341]     3.77  2781 1.00
## mu[342]     6.60  3368 1.00
## mu[343]     5.23  2839 1.00
## mu[344]     3.57  2433 1.00
## mu[345]     2.62  2130 1.00
## mu[346]     2.96  2760 1.00
## mu[347]    12.03  3705 1.00
## mu[348]    25.95  2700 1.00
## mu[349]    18.06  3784 1.00
## mu[350]     7.83  3249 1.00
## mu[351]    27.38  3060 1.00
## mu[352]    15.74  3482 1.00
## mu[353]     6.64  2828 1.00
## mu[354]   202.46  3639 1.00
## mu[355]     7.28  2553 1.00
## mu[356]     4.96  2226 1.00
## mu[357]    10.75  2614 1.00
## mu[358]    94.69  3859 1.00
## mu[359]     8.86  3484 1.00
## mu[360]     8.22  2711 1.00
## mu[361]     1.73  2221 1.00
## mu[362]    41.11  3615 1.00
## mu[363]    14.00  3006 1.00
## mu[364]     3.61  1985 1.00
## mu[365]    15.37  3495 1.00
## mu[366]    14.18  2534 1.00
## mu[367]    25.07  2675 1.00
## mu[368]     4.03  2580 1.00
## mu[369]    15.42  3114 1.00
## mu[370]    30.91  2444 1.00
## mu[371]     7.11  2494 1.00
## mu[372]    20.20  2644 1.00
## mu[373]    15.67  3239 1.00
## mu[374]     3.90  2229 1.00
## mu[375]     9.39  2207 1.00
## mu[376]    19.37  3107 1.00
## mu[377]    12.66  3347 1.00
## mu[378]    15.74  2805 1.00
## mu[379]    30.95  4512 1.00
## mu[380]     9.07  3036 1.00
## mu[381]     4.46  3358 1.00
## mu[382]     4.80  2016 1.00
## mu[383]     3.35  2234 1.00
## mu[384]     5.56  2534 1.00
## mu[385]    16.94  3084 1.00
## mu[386]     3.01  2094 1.00
## mu[387]     4.76  2637 1.00
## mu[388]    11.75  3059 1.00
## mu[389]    15.27  3323 1.00
## mu[390]     7.55  2226 1.00
## mu[391]     5.04  3457 1.00
## mu[392]     8.69  2993 1.00
## mu[393]    30.82  3189 1.00
## mu[394]     3.94  1718 1.00
## mu[395]    18.15  3384 1.00
## mu[396]     9.96  2723 1.00
## mu[397]     3.40  2471 1.00
## mu[398]   104.45  3539 1.00
## mu[399]     5.54  2975 1.00
## mu[400]    21.97  3358 1.00
## mu[401]     9.35  2643 1.00
## mu[402]    20.85  3475 1.00
## mu[403]     3.32  3076 1.00
## mu[404]    23.92  3152 1.00
## mu[405]    52.31  4241 1.00
## mu[406]    10.04  3393 1.00
## mu[407]     3.76  2618 1.00
## mu[408]    72.06  3377 1.00
## mu[409]    12.55  4181 1.00
## mu[410]     9.33  2509 1.00
## mu[411]    12.15  2666 1.00
## mu[412]    11.29  2876 1.00
## mu[413]     4.65  3061 1.00
## mu[414]     3.13  2196 1.00
## mu[415]     9.11  2885 1.00
## mu[416]     9.87  4072 1.00
## mu[417]     7.28  2557 1.00
## mu[418]    16.62  3477 1.00
## mu[419]     7.03  2708 1.00
## mu[420]    37.89  3023 1.00
## mu[421]    12.80  2957 1.00
## mu[422]    17.90  2571 1.00
## mu[423]     5.08  2698 1.00
## mu[424]    10.56  3479 1.00
## mu[425]    17.34  3202 1.00
## mu[426]    23.47  2210 1.00
## mu[427]     3.06  1948 1.00
## mu[428]    11.75  3632 1.00
## mu[429]     4.38  2423 1.00
## mu[430]     4.58  2246 1.00
## mu[431]     6.58  2756 1.00
## mu[432]    15.29  3026 1.00
## mu[433]    26.55  3110 1.00
## mu[434]     7.20  2292 1.00
## mu[435]    11.83  3065 1.00
## mu[436]    11.39  2670 1.00
## mu[437]    11.38  1992 1.00
## mu[438]     4.55  2068 1.00
## mu[439]    11.35  2691 1.00
## mu[440]    28.01  2583 1.00
## mu[441]     8.51  3029 1.00
## mu[442]     5.25  2372 1.00
## mu[443]    98.66  3529 1.00
## mu[444]     8.63  3355 1.00
## mu[445]     7.15  2521 1.00
## mu[446]     6.62  2388 1.00
## mu[447]     7.63  3108 1.00
## mu[448]     7.15  2158 1.00
## mu[449]    20.45  2643 1.00
## mu[450]     3.96  2657 1.00
## mu[451]     7.89  3593 1.00
## mu[452]     5.80  2780 1.00
## mu[453]     3.41  1569 1.00
## mu[454]     3.36  2492 1.00
## mu[455]     2.55  1644 1.00
## mu[456]     9.87  3100 1.00
## mu[457]     3.70  2086 1.00
## mu[458]     9.85  2759 1.00
## mu[459]    43.93  2213 1.00
## mu[460]     6.18  3545 1.00
## mu[461]    11.06  2675 1.00
## mu[462]    10.32  2867 1.00
## mu[463]     2.98  2884 1.00
## mu[464]     3.55  3039 1.00
## mu[465]     8.57  2940 1.00
## mu[466]    24.48  3596 1.00
## mu[467]     5.23  2596 1.00
## mu[468]     3.38  2607 1.00
## mu[469]     7.14  3395 1.00
## mu[470]    39.82  3443 1.00
## mu[471]     3.88  2552 1.00
## mu[472]    28.81  2955 1.00
## mu[473]     7.05  3186 1.00
## mu[474]    14.45  3113 1.00
## mu[475]    25.71  3010 1.00
## mu[476]    25.13  3945 1.00
## mu[477]    15.30  2776 1.00
## mu[478]    29.70  2340 1.00
## mu[479]    25.10  2772 1.00
## mu[480]    20.15  3059 1.00
## mu[481]     5.83  3416 1.00
## mu[482]    13.19  2842 1.00
## mu[483]     9.20  2639 1.00
## mu[484]    13.89  2887 1.00
## mu[485]     5.34  2769 1.00
## mu[486]    11.31  3057 1.00
## mu[487]   111.87  2655 1.00
## mu[488]    23.25  2907 1.00
## mu[489]     2.95  2181 1.00
## mu[490]     7.44  2940 1.00
## mu[491]    80.47  2224 1.00
## mu[492]    13.28  2813 1.00
## mu[493]     3.77  2611 1.00
## mu[494]    11.21  2784 1.00
## mu[495]     5.42  2190 1.00
## mu[496]     6.08  2310 1.00
## mu[497]    29.13  2752 1.00
## mu[498]   211.38  3301 1.00
## mu[499]     9.80  2040 1.00
## mu[500]     7.58  3233 1.00
## a[1]        1.81  1562 1.00
## a[2]        1.57  1632 1.00
## b           0.96  2223 1.00
## c[1]        0.40  2681 1.00
## c[2]       -0.03  1518 1.00
## sigma       1.04   891 1.00
## lp__    12781.31   429 1.01
## 
## Samples were drawn using NUTS(diag_e) at Sat Jan  5 13:00:41 2019.
## For each parameter, n_eff is a crude measure of effective sample size,
## and Rhat is the potential scale reduction factor on split chains (at 
## convergence, Rhat=1).

plot of chunk trace_fullmodel

How’d we do now?

Here are posterior distributions from the full model, with the true values in red. plot of chunk true_fit

Posterior predictive simulations, again

Now we cover the true data

plot of chunk plot_post_sims2

Now we cover the true data

plot of chunk plot_post_sims3

Model comparison

How to compare the two models?

Two models:

  1. counts ~ poisson(exp(a + b * age + c * exposure))

  2. counts ~ poisson(logNormal(a + b * age + c * exposure))

We just saw some plots that showed that the true data lay outside the range of the simulated data from (1) but not (2).

That was not a formal test.

We need a statistic!

Brainstorm: how can we quantify what we just saw?

Goal: come up with a single number that quantifies how much the observed data “looks like” the posterior predictive samples.

Then, the model with a better score fits better.

plot of chunk plot_model_fit

Same plot, zoomed in:

plot of chunk plot_model_fit2

A toy problem

Is it plausible that \[ X \sim \Normal(A, A)?\] What about \(Y\)?

data.frame(
  A = c(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10), 
  X = c(-0.45, -0.16, 0.15, 0.43, 0.59, 0.87, 1.1, 1.51, 2.3, 2.42,
         -7.98, -2.49, 5.15, 5.86, 7.36, 8.52, 10.53, 13, 15.51, 18.8), 
  Y = c(-2.18, -1.47, 0.18, 0.64, 0.81, 1.18, 2.52, 2.87, 3.08, 3.1, 
         -49.03, -38.01, -28.81, 0.16, 9.89, 25.92, 39.1, 49.3, 50.87, 92.11))

Goodness-of-fit: design

We’ll use the fact that if the simulated data “look just like” the real data, then the rank of the real data in the simulated data should be uniform.

Since we have 100 simulated datasets, that means that the probability that the real data is smaller than all the simulated data is \(1/101\), and the probability that the real data is bigger than only one of the simulated data points is \(1/101\), etcetera.

This is a distribution-free measure of goodness of fit.

Warm-up

To check that we understand what’s going on here, we’re doing to simulate data where the “sample” fits the model, so that the “sample” and the “simulations” are from the same distribution.

plot of chunk a_hist

Chi-squraed for goodness of fit.

If \(N_i \sim \Poisson(P_i)\), then the mean and variance of \(N_i\) is \(P_i\). This motivates the chi-squared statistic: \[ \chi^2 = \sum_i \frac{(N_i - P_i)^2}{P_i} . \]

Goodness-of-fit: implementation

The goodness-of-fitscores obtained by our models were

  1. Original model: 978
  2. Second model, with more randomness: 33

Here is the “null distribution” of the goodness-of-fit scores. The first model is clearly outside this range, and the second one is on the edge.

plot of chunk show_gof_hist