Hi Nezahat, First, you are storing the code of the function "numeric" in x1 and x2. You probably want to use:
x1<-numeric() x2<-numeric() Second, you are then storing the output of your aov summary (a list) in x1, which requires a bit of analysis to get the information you want (i.e. p value). The following will work for your example, but is not a general solution. nh_fun<-function(x) { pvals <-numeric() for(i in 2:length(x)) pvals[i-1]<-unlist(summary(aov(x[,i] ~ factor(x[,1])))[[1]][5])[1] <= 0.05 return(pvals) } nh_fun(x) As you probably want to get the conventional <=0.05, I have changed the criterion. If you want to understand why the mess of extractors appears after the "summary" call, use the "str" function successively on the return value from "summary" Jim On Fri, May 29, 2015 at 7:16 AM, Nezahat HUnter <nezahathun...@yahoo.co.uk> wrote: > > Let's say I have 12 observation of 5 variables and my first variable is > categorical (with 4 different levels). I am trying to find out statistical > significance difference between these categorical levels for each variable, > but my function is not working! Please note that my data "x" are in > data.frame format. > Any suggestion would be helpful.Many thanks. > > function(x) > { > x1 <- numeric > x2 <- numeric > for(i in 2:length(x)) { > x1[i] <- summary(aov(x[, i] ~ factor(x[, 1]))) > x2[i] <- x1[i]$Pr[1] #Pr is the probability values > if(x2[i] < 0.06) > x2[i] <- 1 > else x2[i] <- 0 > } > x2 > } > > > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.