Advanced Stata topics

• Merging data. Check this page from UCLA describing merging. You can also read more about it on the section Combining Two or More Stata Files in the Hamilton book (version 12) on page 46.
• Converting strings to numbers. That is done with the destring command and the UCLA website describes this command in more detail. There is a short example with destring on page 39 of the Hamilton book.
• Create date variables. A related task to working with strings is converting strings into date variables that will be properly recognized by Stata. This UCLA page shows how to do it.
• Power and Sample size. Probably one of the most significant updates in Stata 14 is expanded tools for power and sample size calculations. This is mainly done via the power command. Stata also created a set of tutorial videos on how to do these calculations. Like I said, some scenarios are very complicated and need simulations for approximating power and sample size calculations. But this is a very good start. Finally, I haven’t used this website but it seems useful.

List of links (in case you are printing this page):

• http://www.ats.ucla.edu/stat/stata/faq/multmerge.htm
• http://www.ats.ucla.edu/stat/stata/faq/destring.htm
• http://www.ats.ucla.edu/stat/stata/faq/string_dates.htm
• http://www.stata.com/features/power-and-sample-size/
• https://www.youtube.com/playlist?list=PLN5IskQdgXWmExGRjdy0s0VCdYnzGMZrT
• http://powerandsamplesize.com/

Remember that all the material can I made and is public is available at https://github.com/lcolladotor/kandahar. The restricted access material is available via http://courseplus.jhu.edu/.