We have run into this issue before: you have $latex n \geq 2$ datasets with $latex 1 < k \leq n$ different coding schemes for the cross-sectional unit. You need to get them all standardized so you can merge the data and
increase the measurement error control for a reviewer's favorite variable run some models.
Last week I was about to spend some time merging alphanumeric ISO codes with their COW counterparts, when I ran across the new
countrycode package in
R.* The package uses regular expressions to convert between the following supported formats:
- Correlates of War character
- IMF numeric
- FIPS 10-4
- FAO numeric
- United Nations numeric
- World Bank character
- ofﬁcial English short country names (ISO)
* New here meaning I didn't know about it before and its documentation is dated Jan. 20, 2013.