st: Control variable and stationarity

[RASHAD HASANOV <rhasanov@deakin.edu.au>]

Hi guys,

I dont have great econometric background. so the questions might seem silly for you. I am writing a paper on debt crises. using panel logit model. the left hand side is 0 and 1 standing for non-crisis year and a year when debt crisis happens. and the right
 hand side contains the vector of explanatory variables such as gdp growth, debt to gdp ratio etc.  I am using fixed effects model.



I got 2 comments from the reader. 1. have you checked for stationarity of variables? as they stationary?

2. what are the control variables?


so, I am asking my 2 questions

1. how do I do stationarity test before running panel regression in Stata?

2. Coud you please give me more information on control variable? I know, it is a variable that you keep constant to check for other's effects. but I have not used any control variable. should i add it somehow? or can I run this regression without having
 control variables? how does it work? sorry it might seem odd, but I have run these regressions only reading some chapters and links from Stata web site. please help me. thanks






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