Bayesian Estimation of Coefficient Alpha Using a Normal Posterior: Non‑normal Distributions

Abstract

An alternative method for obtaining a Bayesian estimate for coefficient alpha by way of a posterior normal distribution was recently proposed. The performance of this method was initially assessed using Bayesian credible intervals (CrIs) via simulation under mundane conditions to establish baseline performance. It was found to generally have good performance under that set conditions. However, the performance of the alternative method using non-normal data was not assessed. Here, the alternative method is assessed using CrIs via simulation with a focus on non-normal data. Again, it was found that the alternative method generally had good performance. However, there were instances of poor performance when data came from simulation conditions that resulted in items being binary, non-normal, or not varying enough.