I want to understand this paper on brain tumour segmentation.
How is this equation read?
I'm guessing $q_i(t_i)$ represents the likelihood of tumour on voxel i.Is q usually used to represent likelihoods?
What does the equal sign with the triangle mean?
I understand what each term on the conditional probability represents, but I don't get why it's called proportional to the product of the summation. I'm looking for a reading reference here.