Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
st: Number of observations: xtreg and xtivreg2
From
"Abou Nabout, Nadia" <[email protected]>
To
"[email protected]" <[email protected]>
Subject
st: Number of observations: xtreg and xtivreg2
Date
Wed, 29 Sep 2010 09:05:12 +0000
Dear Statalist readers,
I am running a fixed effects model on a dataset with about 97,000 observations.
While xtreg seems to use all these observations (xtreg ln_cpc position t qs qs_sq, i(keyword_id) fe), xtivreg2 (2SLS model with fixed effects: xtivreg2 ln_cpc t qs qs_sq (position=aktgebot), fe) only uses about 96,000 of these observations. I checked all the variables and instruments for missing values but there are none. I also do not have any lagged dependent variables in there, so I am wondering why the number of observations is lower for xtivreg2 compared to xtreg.
Any help would be highly appreciated!
Best,
Nadia
*
* 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/