Hello, I would like to merge MSCI and Compustat data using the following code:
For MSCI data:
egen yrtic = concat (Ticker year)

For Compustat data:
egen yrtic = concat (tic fyear)
joinby yrtic using "Data_MSCI.dta"

however I get the following error: variable yrtic not found
r(111);

Can anyone explain how to make this work?