For an assignment I have to compute the intra-class distance and use it as an objective function to select features. This is for the MNIST dataset.
While I have a fairly good handle on other aspects of this assignment, the term intra-class distance is confusing to me. Google does not result in any concrete answers either.
I understand intra would mean within, but that's exactly what is confusing to me: how can distance be within? Is it the distance of each measurement with another?
For example, I have N measurements for Class C. Is intra-class distance the distance from n to N-1 measurements within that class?