Wilson Interval Bounds

Problem

Return the Wilson score interval [low, high] for successes out of n with critical value z, clamping the bounds to [0, 1]. The center is (p + z^2 / (2n)) / (1 + z^2 / n) and the half-width is z * sqrt(p(1-p)/n + z^2/(4n^2)) / (1 + z^2 / n). Return [0.0, 0.0] when n <= 0.

Test cases

case 1

in: [10,20,1.96]

expected: [0.2992949144298199,0.7007050855701801]

case 2

in: [0,10,1.96]

expected: [0,0.2775401687666166]

case 3

in: [10,10,1.96]

expected: [0.7224598312333834,1]

case 4

in: [0,0,1.96]

expected: [0,0]

Starter codePython

def wilson_bounds(successes, n, z):
    # Your code here
    pass

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