which of the following is more appropriate to cluster a variable? how to reduce the number of variables how to minimize variable number in a cluster analysis what is pca and what are the advantages clustering definition how to reduce the number of variables in a pca when do you use cluster algorithms how to reduce number of variables in clustering pca and clustering in math definition when to use pca clustering do you have to cluster a variable when there are n variables why do you use clustering algorithms what is pca clustering approach? how to reduce the number of variables pca how many variables which algorithm reduces the number of variables in a cluster what is the natural approach of clustering why is clustering used what is the difference between clustering pca and pca do you use clustering algorithm or pca