The Long Term Impact of Adolescent Risky Behaviors and Family Environment. Weibull Regression

08/01/2001

The Weibull distribution is one of the distributions used in modeling survival or duration data. The variable of interest in the analysis of duration is the length of time that elapses from the beginning of some event either until its end or until the measurement is taken, which may precede termination. In our study, we apply Weibull regression to the age when reached 2 years of tenure with one employer after ending formal schooling. The starting point is the age when formal schooling ended and the ending point is when two years of tenure was reached.

The Weibull distributional function is nonlinear. To keep the interpretation of results comparable, we present results in the form of marginal effects as well. Marginal effects measure changes in an outcome variable resulting from a unit change in an independent variable. For example, in estimating age when reached 2 years of tenure after ending formal schooling, we obtained a marginal effect of -1.003 for males relative to females (whose marginal effect is set to 0). This means it took male respondents on average 1.003 years less than female respondents to reach 2 years of tenure after ending formal schooling.