Stata Panel Data Fixed File

This output is invaluable: it shows variation, between variation (across individuals), and within variation (over time for the same individual). High within variation is good for fixed effects models.

You cannot estimate the coefficients of time-invariant variables (like gender or geography) because they drop out of the model during the within-transformation. Random Effects (RE) Model stata panel data

Before analysis, you must declare the data to be panel data. This output is invaluable: it shows variation, between

Alternative to FE when errors are strongly serially correlated. between variation (across individuals)

xtreg ln_wage grade age c.age#c.age ttl_exp, fe

timevar : The variable identifying the time period (e.g., year , quarter , month ). Example Setup