Identifying causal relationships from observational data is not easy. Still, researchers are often interested in examining the effects of policy changes or other decisions. In those analyses, ...

It is well known from the Monte-Carlo work of Nerlove that using the standard within-group estimator for dynamic models with fixed individual effects generates estimates which are inconsistent as the ...

Central to the idea of variance components models is the idea of fixed and random effects. Each effect in a variance components model must be classified as either a fixed or a random effect. Fixed ...

Identification and estimation of the return to schooling in models with fixed effects is also discussed. Although schooling is often treated as time-invariant, schooling increases over a five-year ...

When members of a cohort are grouped, mixed-effects models are often used to fit to exposure data, as these models allow an analyst to treat the group as either a fixed or a random effect.