While running the vglm() with specification of cumulative(link=cloglog) with a more complicated model, the following errors appeared. How to go about solving it? Error in if ((temp <- sum(wz[, 1:M, drop = FALSE] < wzepsilon))) warning(paste(temp, : argument is not interpretable as logical In addition: Warning message: In Deviance.categorical.data.vgam(mu = mu, y = y, w = w, residuals residuals, : fitted values close to 0 or 1 Thanks. TK [[alternative HTML version deleted]]