true positive = predicted being positive and experimentally being positive
false positive = predicted being positve and experimentally being negative
of course the definition of positive and negative are interchangable. and thus
sensitivity (which is TP/all P) and specificity (which is TN/all N) are
interchangable. where all P=TP+FN, and all N=TN+FP
it's more likely to be the case that to make the thing you "want to see"
to be positive.... just an arbitrary definition.
probability of test posit
