Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.
| From | Neil Shephard <nshephard@gmail.com> |
| To | statalist@hsphsun2.harvard.edu |
| Subject | st: Re: st: 回复： AW: 回复： st: AW: do file |
| Date | Mon, 8 Mar 2010 11:39:54 +0000 |
On Mon, Mar 8, 2010 at 11:30 AM, lydia huang <lydiahsh@yahoo.com.cn> wrote: > after i use the do-file, i typed -ta _merge-, then it come out a table with the titles in the first row: _merge, Freq., Percent, Cum.,is this the right outcome? Yes, because Martin is suggesting that you look at the tabulation (abbreviated to -ta-) of the '_merge' variable which is created after a -merge- command has been issued to give you an indication of how many observations were unique to each of the two datasets and how many were common to both. I'd be inclined to check in each of the files 'written' and '13' that the "patient_id" variable is indeed unique, and to further read the documentation for the -merge- command (for the version of Stata that you are using, which you've not documented). To check for duplicates you can... duplicates report patient_id Neil -- "... no scientific worker has a fixed level of significance at which from year to year, and in all circumstances, he rejects hypotheses; he rather gives his mind to each particular case in the light of his evidence and his ideas." - Sir Ronald A. Fisher (1956) Email - nshephard@gmail.com Website - http://slack.ser.man.ac.uk/ Photos - http://www.flickr.com/photos/slackline/ * * 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/