Hi Ista, I tried to use R --vanilla but unfortunately it didn't work either. Here's the output: Error in is.null(subset) : 'subset' is missing [1] "ls" "ls-mi" "MI" A single object matching ‘summary.MI’ was found It was found in the following places registered S3 method for summary from namespace Zelig namespace:Zelig with value function (object, subset, ...) { if (length(object) == 0) stop("Invalid input for \"subset\"") else if (length(object) == 1) return(summary(object[[1]])) getcoef <- function(x) { obj <- x$result if (!isS4(obj)) coef(obj) else if ("coef3" %in% slotNames(obj)) obj@coef3 else obj@coef } res <- list() subset <- if (is.null(subset)) 1:length(object) else c(subset) for (k in subset) res[[k]] <- summary(object[[k]]) ans <- list() ans$zelig <- object[[1]]$name ans$call <- object[[1]]$call ans$all <- res coef1 <- se1 <- NULL for (k in subset) { } } <environment: namespace:Zelig> Moreover, when I type 'summary(z.out,subset=1:length(z.out))' nothing happens. It does not show any output. I will re-install R and the those packages as well. Once again, thanks for your help, Danilo Freire