performance Files

Changes

• check_overdispersion() gets a residual_type argument, to decide whether overdispersion tests are based on simulated or "standard" residuals.

• check_model() gains a ppc_range argument for posterior predictive checks plot. Use this to zoom in on a specific region of interest, especially if the response variable has a large range.

• check_predictions() gains a x_limits argument for plots. Use this to zoom in on a specific region of interest, especially if the response variable has a large range.

• New function check_priors() to conduct prior predictive checks for Bayesian models.

Bug fixes

• The overdispersion plot in check_model() now uses simulated residuals (based on the DHARMa package) for glmmTMB models and mixed models. This fixes wonky-looking overdispersion plots for these model types (#654).

• Fixed the expected variance calculation in .expected_variance() so that glmmTMB nbinom1 and nbinom2 families use the correct formulas from the glmmTMB documentation: nbinom1: V = μ(1 + φ); nbinom2: V = μ(1 + μ/φ). Previously, glmmTMB nbinom1 models incorrectly used the nbinom2 formula because it matched a more general is_negbin branch first (#654).