[R] Problem with dummy variables controlling for years

Hello everybody, I'm running a panel regression with dummy variables controlling for years. While this works fine for most of my models, in some cases I get the error message In sqrt(diag(object$vcov)) : NaNs wurden erzeugt and missing results for some or all of my year dummies:

Re: [R] Problem with dummy variables controlling for years

Hi Johannes. My guess is that you will get no Std. Error, if you have only 1 observation for that year. Could that be the case ? On Mon, Mar 2, 2009 at 8:41 PM, Johannes Habel johannes.ha...@gmx.dewrote: Hello everybody, I'm running a panel regression with dummy variables controlling for