# log likelihood for stackloss fit require(quantreg) data(stackloss) logLik.rq.process <- function(fit){ y <- model.response(model.frame(fit)) fhat <- predict(fit, type = "fhat") fy <- mapply(function(f,y) f(y), fhat, y) sum(log(fy)) } # First try with full process estimates f0 <- rq(stack.loss ~ 1, tau=-1) f1 <- rq(stack.loss ~ stack.x, tau=-1) l0 <- logLik(f0) l1 <- logLik(f1) # Now try with discrete process estimates f0 <- rq(stack.loss ~ 1, tau=1:19/20) f1 <- rq(stack.loss ~ stack.x, tau=1:19/20) l0 <- logLik(f0) l1 <- logLik(f1)