Panel data, also known as longitudinal data, is a type of data that consists of observations on the same units (e.g., individuals, firms, countries) at multiple points in time. Stata is a powerful software package for analyzing panel data, and this guide will cover the essential commands and techniques for working with panel data in Stata.

To follow the "exclusive" path, you need to escape the xtreg, fe comfort zone. Begin with a robust environment:

xtreg y x1 x2, re

// Compare models xtreg y x1 x2, fe estimates store fe xtreg y x1 x2, re estimates store re xtdpdsys y x1 x2, lags(1) estimates store sysgmm esttab fe re sysgmm using panel_compare.rtf, replace /// b(3) se(3) star(* 0.10 ** 0.05 *** 0.01) /// scalar(N r2) title("Panel Model Comparison")

Stata's xt commands require data in , where each row represents one entity at one point in time. Long Format (Required): ID, Year, Variable1, Variable2.