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From | Shubhabrata Mukherjee <joy_stat@yahoo.com> |
To | stata forum <statalist@hsphsun2.harvard.edu> |
Subject | st: Merge problem; missing observation |
Date | Thu, 9 Feb 2012 12:45:39 -0800 (PST) |
Hi, I have two files with the same # of observations but when I try to merge them somehow the merged dataset has one less observation. I checked that there was no observations which was dropped. What am I dong wrong here? Thanks, -Joey E.g. ############# File A duplicates report snp -------------------------------------- copies | observations surplus ----------+--------------------------- 1 | 691677 0 -------------------------------------- ############# File B duplicates report snp -------------------------------------- copies | observations surplus ----------+--------------------------- 1 | 691677 0 -------------------------------------- ##################### merge file A with file B merge m:1 snp using fileB, assert(match master) keep(match) Result # of obs. ----------------------------------------- not matched 0 matched 691,676 (_merge==3) ----------------------------------------- * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/