* Graph marginal effect and z-statistic values (Figure 2)
graph twoway (scatter ie pprob)|| ///
(scatter z stat pprob, yaxis(2) yline (-1.96 1.96, axis(2)))
我参考的代码长这个样子,运行下面两行之后显示的2 invalid name r(198) ,应该怎么解决呢 谢谢啦~