I am doing panel data analysis and some of my variables have high kurtosis. I am not sure whether I have to transform these variables.
I have tried to delete outliers but one of the variables still not normal unless I delete many observations which then change the results to insignificant model
note: this variables has a maximum of around 17,000,000 and min of – 5000,000 which i couldn't use log transform
any help is appreciated. thanks
Best Answer
You don't have to have normally distributed variables to do panel data analysis (and you probably shouldn't drop outliers unless you think for some reason they are measured incorrectly). Fixed effects estimation will consistently estimate the parameters without normality. However, you may need to correct the standard errors that you compute, but most software packages will probably do this for you. For example, R's plm package looks like it will give you the correct standard errors by default. See Section 3.4 of the vignette: http://cran.r-project.org/web/packages/plm/vignettes/plm.pdf
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