Reviews and comments on Stoolmiller's (1998) criticisms of an epidemic model of the onset of social activities (EMOSA) and about nonlinear modeling in general. Discusses the idea of social contagion as a general theoretical tool. (Author)

Expands an existing nonlinear dynamic epidemic model of onset of social activities (EMOSA), motivated by social contagion theory, to quantify the likelihood of pregnancy for adolescent girls of different sexuality statuses. Compares five sexuality/pregnancy models to explain variance in national prevalence curves. Finds that adolescent girls have…

Investigated genetic and environmental contributions to relationship between family and school environment and depressed mood; also potential sex differences in genetic and environment contributions to variation in and covariation between family connectedness, school connectedness, and depressed mood. Subjects were 2,302 adolescent sibling pairs.…