Longitudinal panel studies are widely used in developmental science to address important research questions on human development across the lifespan. These studies, however, are often challenging to implement. They can be costly, time-consuming, and vulnerable to test--retest effects or high attrition over time. Planned missingness designs (PMDs),…

Developmental scientists are often interested in subgroups of people who share commonalities in aspects of development; these subgroups often cannot be captured directly but instead must be inferred from other information. Mixture models can be used in these situations. Two specific types of mixture models, latent profile transition analyses and…

Adolescent boys perceive their male peer group culture--and their socialization toward masculine norms emphasized within this culture--as negatively influencing their abilities to develop close male friendships. Boys who manage to develop close, male friendships, however, draw strength from these relationships to resist the social pressures of…