Bayesian-style reliability estimate (Bignardi, Kievit & Bürkner, 2025)
computed from a matrix of posterior or plausible-value draws. The columns of
input_draws are split at random into two halves; reliability is the
Pearson correlation across persons of paired columns from the two halves,
summarised across pairs as a posterior mean with HDCI.
Value
A 1-row data.frame with columns rmu_estimate, hdci_lowerbound,
hdci_upperbound, plus the .width/.point/.interval metadata
columns added by ggdist::mean_hdci().
Details
Adapted (with permission, GPL-2/3) from https://github.com/giac01/gbtoolbox/blob/main/R/reliability.R.
The function silently returns 0 for any column pair where either side has zero variance (the correlation is undefined there).
Requires the ggdist package (Suggests).
References
Bignardi, G., Kievit, R., & Bürkner, P. C. (2025). A general method for estimating reliability using Bayesian Measurement Uncertainty. PsyArXiv. doi:10.31234/osf.io/h54k8_v1