I've seen the pattern ABA', where A and B are matrices, and ' stands for the transpose, many times so I want to know if there is an intuition for this pattern.
I did some development to see what the resulting matrix would look like and I got this:
Let A be a matrix of dimensions (l,m),
B be a matrix of dimensions (m,m) and
R = ABA'. with dimensions (l,l)
Then:
- Is my development correct?
- When does this pattern occur? (I've seen it a lot in machine learning).
One context where I've seen this pattern is in the equations of the Kaman filter (taken from wikipedia) :