I am working on cluster analysis of a completely categorical data set using package
klaR and function
kmodes. A sample of the data is available on dropbox. Just cross the sign-up notification dropbox will show when link opens.
The code to do the clustering was simple enough.
require(klaR) c1 <- kmodes(df, 5, 5, weighted = FALSE)
My questions are:
How do I visualize these clusters? I have done simple plots in the past with k-means clusters:
plotcluster(data, clus$cluster). When I try this here, I get:
Error: is.numeric(x) || is.logical(x) is not TRUE
How do I decide optimal number of clusters? I've read through Cluster analysis in R: determine the optimal number of clusters on Stack Overflow, but there is no mention of categorical variables anywhere and I could not understand which of the several methods discussed by the author will be applicable in my case.