One-Proportion z-Statistic

Problem

Return the one-proportion z-statistic (p_hat - p0) / sqrt(p0*(1-p0)/n), where p_hat = successes/n. Return 0.0 when n <= 0 or p0 is not strictly between 0 and 1.

Hint

The standard error uses the hypothesized proportion p0, not p_hat.

Test cases

case 1

in: [45,100,0.5]

expected: -0.9999999999999998

case 2

in: [60,100,0.5]

expected: 1.9999999999999996

case 3

in: [10,50,0.2]

expected: 0

case 4

in: [0,0,0.5]

expected: 0

case 5

in: [5,10,0.9]

expected: -4.216370213557839

Starter codePython

def one_proportion_z(successes, n, p0):
    # Your code here
    pass

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