Estimating the Reliability and Stability of Emotional Variability Across Time

Interest in emotional variability as an interindividual difference is growing. Yet, basic features of the construct, such as its stability and reliability, are not well understood. To address this gap, we examined two longitudinal data sets, each comprising two waves of daily assessments, one with a 3-month and the other with a 16-month retest interval. Overcoming a key methodological limitation of past approaches, we used Bayesian censored location scale models as an alternative modeling approach that accounts for biases introduced by bounded rating scales. The results showed that the variability estimates from the models had reliabilities around rel = .64, which can be sufficient for group-level predictions. Additionally, the latent stability of r = .60 provides evidence for stable individual differences in emotional variability, suggesting that it is more than just a transient state. We ran exploratory analyses to further examine the influence of external events and individual life transitions on emotional variability and found that emotional variability was responsive to environmental changes.