search for: walhus

...random model with individual effect.  data.re.ind <- plm(X.RETURN. ~ IOB + IOBS,data=E,model="random",effect = "individual")  Error in swar(object, data, effect) :  the estimated variance of the individual effect is negative  I have tried the other estimation methods ("walhus", "amemiya", "nerlove") in addition to method "swar" but it does not help.  I have googled for answer but I have not found the solution yet. Actually this problem encountered by some users but still remains unsolved, I am afraid. Would some people help in this re...

...en get the summary of "dsn" with >summary(dsn) which works fine also, however my problem starts when i define my model and i cant find where do i make mistake!! i try to create my model with the following command >dsn.plm <- plm(lnQ~lnC+lnL+lnM+lnE,data=ds, random.method="walhus",effect="twoways",model="random") and than i get this error message duplicate couples (time-id) Error in pdim.default(index[[1]], index[[2]]) : so my question is; is there anyone who knows how to overcome with this error! for now i dont know if i have to give more info...

...; plm function (formula, data, subset, na.action, effect = c("individual", "time", "twoways"), model = c("within", "random", "ht", "between", "pooling", "fd"), random.method = c("swar", "walhus", "amemiya", "nerlove", "kinla"), inst.method = c("bvk", "baltagi"), index = NULL, ...) { nframe <- length(sys.calls()) is.a.list <- class(formula)[1] == "list" if (is.a.list) { plmlist <- match.ca...