一个例子。复制粘贴就应该能运行。
webuse nlswork
xtreg ln_w grade age c.age#c.age ttl_exp c.ttl_exp#c.ttl_exp tenure c.tenure#c.tenure 2.race not_smsa south, fe
* u u_i, the fixed- or random-error component
predict u, u
* e e_it, the overall error component
predict e, e
su u e