Posterior-predictive checks of the fitted model

Three checks, each comparing the observed sorts with replicates drawn from the fitted model: the agreement check (T1a) compares the observed person-agreement matrix with replicated ones against a double-replicate reference; the extra-factor check (T1b) locates the observed (K+1)-th eigenvalue in its replicated distribution; and the paired-comparison check (T2) compares standardized statement-pair margins, ties counted one half. These are diagnostics to read, not tests to pass.

Usage

check_fit(fit, draws = 100)

Arguments

fit

A bayesqm_fit.

draws

Posterior draws used for replication (default 100).

Value

A bayesqm_checks list: agreement (p), extra_factor (percentile), and paired (p, per-statement p_j), with a print method.

Examples

check_fit(demo_fit(), draws = 20)
#> Posterior-predictive checks (20 replicated draws):
#>   agreement check (T1a):        p = 0.60
#>   extra-factor check (T1b):     observed e_(K+1) at percentile 0.35
#>   paired-comparison check (T2): p = 0.30 (worst statement 0.15)
#>   diagnostics to read, not tests to pass