Module platt 

Platt scaling: an SVM’s decision values turned into probabilities, P(spam | f) = 1 / (1 + exp(A·f + B)), fitted on scores the SVM gave to messages it had not learned from (Platt 1999). Fitted by Newton’s method with a backtracking line search, as Lin, Lin & Weng (“A note on Platt’s probabilistic outputs for support vector machines”, Machine Learning 68, 2007) wrote it: their targets, their stopping rule, a stable log-loss.

Structs

Platt

A and B of the sigmoid.

Functions

fit

Fits A and B on (decision value, is spam) pairs; None without both kinds.