// 随机生成面板数据

local N = 10 // 研究对象的个体数
local T = 3  // 研究的年份
local NT = `N'*`T'
set obs `NT'
set seed 123  // 种子值
egen id =seq (),from (1) to (`N') block (`T') // 设定 T,N 的值
sort id
by id: gen year = _n + 2017
xtset id year

//变量生成
gen income = 200+rnormal()
gen edu = 9+7*uniform()
br


xtset id year
xtsum 


xtline income,overlay