Sigmoid — a squash into (0, 1)
σ(z) = 1 / (1 + e^(−z)): maps any real number into the range 0 to 1, with σ(0) = 0.5.
It is the two-class softmax, and the Bradley–Terry model of preferences uses it on a difference of scores (section 3.6).
σ(z) = 1 / (1 + e^(−z)): maps any real number into the range 0 to 1, with σ(0) = 0.5.
It is the two-class softmax, and the Bradley–Terry model of preferences uses it on a difference of scores (section 3.6).