The author of these notes, mentions 3 different graph Laplacians. Each of these creates a different measure of group size when used in spectral clustering. She offers a proof for each, but I would like to read more about constructing a Laplacian. What is written there is a little too terse for me to really understand.
Can anyone recommend some reading that would cover the various choices of graph Laplacian and relate them to their measure of cluster size?