The apply function coerces the factor results to a character array apply(g,2,class) # gives character
The kruskal.test function doesn't take character vector as the group argument. kruskal.test(as.character(plant.height) ~ as.character(g[,8])) #doesn't work kruskal.test(plant.height ~ as.character(g[,8])) #doesn't work kruskal.test(as.character(plant.height) ~ g[,8]) #works You'd better change the kw function. kw <- function(x) kruskal.test(plant.height ~ as.factor(x))$"p.value" ----- A R learner. -- View this message in context: http://r.789695.n4.nabble.com/Kruskal-Walllis-test-tp2311712p2312063.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.
