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| From | Andreas Dimopoulos <ad382@sussex.ac.uk> |
| To | <statalist@hsphsun2.harvard.edu> |
| Subject | Re: st: RE: merging - unique observations |
| Date | Sun, 06 Apr 2014 22:54:24 +0100 |
Thanks a lot. It seems to be correct with the method you suggested! Regards, A On Sun, 6 Apr 2014 15:23:35 +0900, "Joseph Coveney" <stajc2@gmail.com> wrote: > Make sure that you get the m:1 or 1:m in the proper order. If not, then > you'll get the error you mentioned. See below. > > Joseph Coveney > > . clear * > > . set more off > > . set linesize 79 > > . > . input str244(reporter partner) int period str2 trade > > >> >> >> reporter >> >> >> >> partner period trade > 1. can usa 2000 k1 > 2. can usa 2002 k2 > 3. end > > . > . tempfile tmpfil0 > > . quietly save `tmpfil0' > > . > . drop _all > > . > . input str244(reporter partner) str2 distance > > >> >> >> reporter >> >> >> >> partner distance > 1. can usa x1 > 2. can arg x2 > 3. end > > . > . * > . * Accidentally got it backwards (gives error message) > . * > . capture noisily merge m:1 reporter partner using `tmpfil0' > variables reporter partner do not uniquely identify observations in the > using > data > > . > . * > . * Got it right, here > . * > . merge 1:m reporter partner using `tmpfil0', /// >> keep(matched) noreport nogenerate > > . > . sort reporter partner period > > . list, noobs sepby(reporter partner) > > +------------------------------------------------+ > | reporter partner distance period trade | > |------------------------------------------------| > | can usa x1 2000 k1 | > | can usa x1 2002 k2 | > +------------------------------------------------+ > > . > . exit > > end of do-file > > -----Original Message----- > From: owner-statalist@hsphsun2.harvard.edu > [mailto:owner-statalist@hsphsun2.harvard.edu] On Behalf Of Andreas > Dimopoulos > Sent: Sunday, April 6, 2014 13:34 > To: statalist@hsphsun2.harvard.edu > Subject: Re: st: RE: merging - unique observations > > My first dataset is like: > > reporter partner period trade > can usa 2000 k1 > can usa 2002 k2 > > and my second dataset is like: > > reporter partner distance > can usa x1 > can arg x2 > > A difference between the datasets is that the second one has every pair of > countries in the sample while the first one not. For example, the pair > CAN-ARG does not exist in the first one. Hope that helps? > > Regards, > A > > > On Sun, 6 Apr 2014 00:35:33 +0000, Joe Canner <jcanner1@jhmi.edu> wrote: >> Andrew, >> >> It is difficult to say for sure what the problem is without more details >> about your data, what command(s) you ran, and the exact error message > you >> received. >> >> However, it appears that at least one of the problems is that your first >> data set has multiple observations per country-pair (one for each year) >> while the second data set has only one observation per country-pair. If >> this is the case, try a many-to-one merge: >> . merge m:1 countrypair using distancedata >> >> I can also imagine other problems that might arise from the use of >> country-pairs as the merging key, but we would have to know more about > your >> data in order to diagnose them. >> >> Regards, >> Joe Canner >> Johns Hopkins University School of Medicine >> >> ________________________________________ >> From: owner-statalist@hsphsun2.harvard.edu >> [owner-statalist@hsphsun2.harvard.edu] on behalf of Andreas Dimopoulos >> [ad382@sussex.ac.uk] >> Sent: Saturday, April 05, 2014 5:47 PM >> To: statalist@hsphsun2.harvard.edu >> Subject: st: merging - unique observations >> >> Good evening, >> >> I have two datasets where the first one contains pairs of countries and >> their in between trade for different years and another dataset which has >> the pair of countries and their in between distance etc (which don't > change >> over time). I tried to merge those two datasets based on the things I > have >> read but stata tells me that the observations cannot be uniquely >> identified. >> >> Any piece of advise? >> >> Regards, >> Andrew >> * >> * For searches and help try: >> * http://www.stata.com/help.cgi?search >> * http://www.stata.com/support/faqs/resources/statalist-faq/ >> * http://www.ats.ucla.edu/stat/stata/ >> >> * >> * For searches and help try: >> * http://www.stata.com/help.cgi?search >> * http://www.stata.com/support/faqs/resources/statalist-faq/ >> * http://www.ats.ucla.edu/stat/stata/ > * > * For searches and help try: > * http://www.stata.com/help.cgi?search > * http://www.stata.com/support/faqs/resources/statalist-faq/ > * http://www.ats.ucla.edu/stat/stata/ > > > * > * For searches and help try: > * http://www.stata.com/help.cgi?search > * http://www.stata.com/support/faqs/resources/statalist-faq/ > * http://www.ats.ucla.edu/stat/stata/ * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/faqs/resources/statalist-faq/ * http://www.ats.ucla.edu/stat/stata/