You're right David, I'm really sorry. I deactivated html, hope now it works.
> R 2.15.2 plm() function on Windows 7. I have a problem with the variance estimation in a random effect model I used this formula to get my result, and it works: > reg <- deltaF ~ L1.deltaF + L2.deltaF + deltaCDS + L1.deltaCDS + L2.deltaCDS > + L3.deltaCDS + deltaUS_Yields + deltaZ + L1.deltaZ. > fixed <- plm(reg, data=Mody_R, na.action = na.exclude, index=c("country_id", > "datestata"), model="random"). but when i split my dataframe into several groups it gives me this error: > "Error in swar(object, data, effect) : the estimated variance of the > individual effect is negative" The code i used to split the dataframe is: > SplitMody <- split(Mody_R, Mody_R$period). > SplitFixed <- lapply(SplitMody, function(Mody_R) plm(reg, data=Mody_R, > na.action = na.exclude, index=c("country_id", "datestata"), model="random")). I want to point the all the code works perfectly in a within model, and I tried using all the random.method for the variance estimation. In addition I used the same random effect model in Stata and it works... (and for the within model the results are identical in R and Stata) I'll be really gratefull if someone can help me. Thanks, Matteo > CC: r-help@r-project.org > From: dwinsem...@comcast.net > To: ognibenemat...@hotmail.it > Subject: Re: [R] plm random effect: the estimated variance of the individual > effect is negative > Date: Thu, 3 Jan 2013 13:23:07 -0800 > > > On Jan 3, 2013, at 8:19 AM, matteo ognibene wrote: > > > > > Hi,R 2.15.2 plm() function on Windows 7 > > I have a problem with the variance estimation in a random effect model > > I used this formula to get my result, and it works:reg <- deltaF ~ > > L1.deltaF + L2.deltaF + deltaCDS + L1.deltaCDS + L2.deltaCDS + > > L3.deltaCDS + deltaUS_Yields + deltaZ + L1.deltaZ + L2.deltaZfixed > > <- plm(reg, data=Mody_R, na.action = na.exclude, > > index=c("country_id", "datestata"), model="random") > > but when i split my dataframe into several groups it gives me this > > error:"Error in swar(object, data, effect) : the estimated > > variance of the individual effect is negative" > > The code i used to split the dataframe is:SplitMody <- split(Mody_R, > > Mody_R$period)SplitFixed <- lapply(SplitMody, function(Mody_R) > > plm(reg, data=Mody_R, na.action = na.exclude, index=c("country_id", > > "datestata"), model="random")) > > I want to point the all the code works perfectly in a within model, > > and I tried using all the random.method for the variance > > estimation.In addition I used the same model in Stata and it > > works... (the results are identical for a within model in R and Stata) > > I'll be really gratefull if someone can help me. > > Thanks,Matteo > > [[alternative HTML version deleted]] > > Head up; matteo: This is pretty much unreadable (due to the failure to > follow the recommended posting procedure.) > > -- > David Winsemius, MD > Alameda, CA, USA > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.