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| From | Maarten Buis <maartenlbuis@gmail.com> |
| To | statalist@hsphsun2.harvard.edu |
| Subject | Re: st: mysterious missing variables after mydate=mdy(month,day,year) |
| Date | Mon, 30 May 2011 17:20:53 +0200 |
On Mon, May 30, 2011 at 4:43 PM, ABDUL ADAM <bihiabdul@yahoo.com> wrote: > Dear List, > > I have a panel dataset where my date is in different variables (month, day, year), I am able to create a single date variable by mydate=mdy(month,day,year). But the thing is after generating this new variable, stata returns (132 missing values generated). I tried to see where these missing values lie? but to my surprise, I cannot find them; even after > su mydate if mydate>=. > I get zero observations. So, I wonder: -sum- will only summarize non-missing values, so -su mydate if mydate>=.- will always return no observations. For this type of inspection of data I like Ben Jann's -fre- command. In your case I would type -fre month day year if mydate >= .-. You can install -fre- by typing in Stata -ssc install fre- Hope this helps, Maarten -------------------------- Maarten L. Buis Institut fuer Soziologie Universitaet Tuebingen Wilhelmstrasse 36 72074 Tuebingen Germany http://www.maartenbuis.nl -------------------------- * * 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/