Hello, I am trying to conduct a Hausman test to choose between FE estimators and RE estimators.
When I try to run: library(plm) fixed <- plm(ROS ~ DiffClosenessC +ZZiele + AggSK + nRedundantStrecken + Degree + KantenGew + BetweennessC + SitzKappazitaet, data=Panel,index=c("id","time"),model="within") summary(fixed) fixef(fixed) random <-plm(ROS ~ DiffClosenessC +ZZiele + AggSK + nRedundantStrecken + Degree + KantenGew + BetweennessC + SitzKappazitaet, data=Panel,index=c("id","time"), model="random") summary(random) phtest(fixed, random) I get an error from phtest(fixed, random) Fehler in solve.default(dvcov) : System ist für den Rechner singulär: reziproke Konditionszahl = ... Error in solve.default(dvcov) : system is computationally singular: reciprocal condition number =... Can someone Help me with this problem or give me a hint where to look? Thanks gloria -- View this message in context: http://r.789695.n4.nabble.com/Hausman-test-error-solve-tp4647793.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.