The print method for stanreg objects displays a compact summary of the
fitted model. See the Details section below for descriptions of the
different components of the printed output. For additional summary statistics
and diagnostics use the summary method.
# S3 method for stanreg
print(x, digits = 1, ...)# S3 method for stanmvreg
print(x, digits = 3, ...)
A fitted model object returned by one of the
rstanarm modeling functions. See stanreg-objects.
Number of digits to use for formatting numbers.
Ignored.
Returns x, invisibly.
Regardless of the estimation algorithm, point estimates are medians computed
from simulations. For models fit using MCMC ("sampling") the posterior
sample is used. For optimization ("optimizing"), the simulations are
generated from the asymptotic Gaussian sampling distribution of the
parameters. For the "meanfield" and "fullrank" variational
approximations, draws from the variational approximation to the posterior are
used. In all cases, the point estimates reported are the same as the values
returned by coef.
The standard deviations reported (labeled MAD_SD in the print output)
are computed from the same set of draws described above and are proportional
to the median absolute deviation (mad) from the median.
Compared to the raw posterior standard deviation, the MAD_SD will be
more robust for long-tailed distributions. These are the same as the values
returned by se.
The median and MAD_SD are also reported for mean_PPD, the sample
average posterior predictive distribution of the outcome. This is useful as a
quick diagnostic. A useful heuristic is to check if mean_PPD is
plausible when compared to mean(y). If it is plausible then this does
not mean that the model is good in general (only that it can reproduce
the sample mean), however if mean_PPD is implausible then it is a sign
that something is wrong (severe model misspecification, problems with the
data, computational issues, etc.).
For GLMs with group-specific terms (see stan_glmer) the printed
output also shows point estimates of the standard deviations of the group
effects (and correlations if there are both intercept and slopes that vary by
group).
For analysis of variance models (see stan_aov) models, an
ANOVA-like table is also displayed.
For joint longitudinal and time-to-event (see stan_jm) models
the estimates are presented separately for each of the distinct submodels.