Natural Parameter to Mean

Problem

Convert the natural parameter of a Bernoulli distribution to its mean:

p = 1 / (1 + exp(-eta))

The logistic sigmoid maps the real line to the interval (0, 1).

Hint

eta = 0 corresponds to a fair coin.

case 1

in: [0]

expected: 0.5

case 2

in: [1]

expected: 0.7310585786300049

case 3

in: [-2]

expected: 0.11920292202211755

case 4

in: [5]

expected: 0.9933071490757153

Starter codePython

import math
def bernoulli_natural_to_mean(eta):
    # Your code here
    pass

4 test cases · run your code against them in the editor