I am wondering if for a PCA for which I rescale my numeric variables, I need to rescale my dummy variables as well ? I have read on the internet that I should not but I do not see why. I guess the ...
I have what I believe to be a simple question. I have also browsed some of the PCA related materials here. I have an unlabeled $M$ by $N$ data matrix, consisting of $M=1000$ points, and $N=500$ ...
I'm doing principal component analysis on my dataset and my professor told me that I should normalize the data before doing the analysis. My question is: "Why?" :) What would happen If I did PCA ...
Suppose we have $N$ measurable variables, $(a_1, a_2, \ldots, a_N)$, we do a number $M > N$ of measurements, and then wish to perform singular value decomposition on the results to find the axes of ...
Related to my previous question, I have a dataset of 2D points with an associated label (this label can take 6 different values). As suggested in the answers to my other question, this can be modeled ...
We have performed a microarray screening of about 200 samples. In each sample we measure about 100 different variables. For technical reasons the screening of these 200 samples was divided into two ...