Temperament is a widely researched trait that significantly influences children's lives. Still, theorists differ in their perspectives on the construct. With their nine dimensions of temperament and three "categories" of children--"easy," "difficult," or "slow to warm up"--Thomas and colleagues (1968) laid…

The use of personality inventories has been limited because of their cost and the length. To overcome these limitations, this study created the Personality Identity Estimator (PIE), an easy-to-use inventory to estimate personality types that can be used at no cost. PIE is a categorical inventory containing 12 items with 3 items for each of the 4…

In order to evaluate the effect of a policy or treatment with pre- and post-treatment outcomes, we propose an approach based on a transition model, which may be applied with multivariate outcomes and accounts for unobserved heterogeneity. This model is based on potential versions of discrete latent variables representing the individual…