>>>>> Gundala Viswanath <gunda...@gmail.com> >>>>> on Sun, 8 Dec 2013 16:11:12 +0900 writes:
> Hi, According to daisy function from cluster > documentation, it can compute dissimilarity when NA > (missing) value(s) is present. > http://stat.ethz.ch/R-manual/R-devel/library/cluster/html/daisy.html > But why when I tried this code > library(cluster) > x <- c(1.115,NA,NA,0.971,NA) > y <- c(NA,1.006,NA,NA,0.645) > df <- as.data.frame(rbind(x,y)) > daisy(df,metric="gower") > It gave this message: > Dissimilarities : > x > y NA > Metric : mixed ; Types = I, I, I, I, I > Number of objects : 2 > Warning messages: > 1: In min(x) : no non-missing arguments to min; returning Inf > 2: In max(x) : no non-missing arguments to max; returning -Inf > I welcome other alternative than gower. > I expect the dissimilarity output gives a non-NA value e.g. 0. What's > the right way to do it? Thank you, Gundala, for using a simple reproducible example. Reading the documentation about Gower's distance a bit more, you'd have found that it works by basically giving weight zero to *pairs* of variable values where one of the two values is missing. In situations like yours, *all* pairs have at least one missing, so there's no way to get a non-NA distance. *AND* the documentation already contains this, at the very end of the section 'Details' : If all weights w_k delta(ij;k) are zero, the dissimilarity is set to ‘NA’. I.e., we have > install.packages("fortunes") > fortune("WTFM") This is all documented in TFM. Those who WTFM don't want to have to WTFM again on the mailing list. RTFM. -- Barry Rowlingson R-help (October 2003) ... which I now did in spite of Barry's excellent point ... let's say it's because of approaching Christmas ! Martin Maechler, ETH Zurich ______________________________________________ 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.