Tobin's Q

[Iulia Andreica]

Hi all,

I am trying to merge two data sets from Compustat to get Tobin's Q. I try to merge the two datasets based on the ISIN number and year. However, the files wont merge. Ive tried duplicates drop and there are no missing data on my datasets. ISIN number is string and year is float. when merging I get the error that the variables are not uniquely identified in the master dataset.

I don't know that the problem might be. Could someone please help me out with this?

Regards,
Iulia

[Andrew Musau]

ISIN and year should uniquely identify observations in at least one of the datasets. You can check this by running:

isid ISIN year

If this is the case, either

merge 1:m ISIN year

or

merge m:1 ISIN year

should work.

[Iulia Andreica]

It worked! thank you !