PDM-EST-003 — Pooled OLS, Fixed Effects, Random Effects, Two-Way Effects, Model Specification and Estimator Selection
Description
This Master Prompt focuses on the core estimation architecture of conventional panel-data analysis and on the reasoning process required to choose among competing specifications. It guides researchers in formulating pooled ordinary least squares, one-way fixed effects, time fixed effects, two-way fixed effects, random effects, correlated random effects/Mundlak-type specifications, and related multidimensional fixed-effects models; identifying what each estimator assumes about unobserved heterogeneity; distinguishing within, between, and overall sources of identifying variation; and interpreting how transformation or inclusion of fixed-effect components changes the estimand and the meaning of coefficients. The uploaded literature confirms that classical FE and RE remain foundational, but also shows that the relationship between unobserved effects and regressors is decisive: when individual effects are correlated with regressors, conventional RE estimation becomes inconsistent while FE can remain consistent under the corresponding assumptions.