MediumStatisticsst-359

Wald Interval Proportion

Problem

The Wald confidence interval for a proportion is p_hat +/- z * sqrt(p_hat (1 - p_hat) / n).

Given p_hat, the sample size, and the critical z, return [lower, upper].

Hint

Center the interval on the sample proportion.

case 1

in: [0.5,100,1.96]

expected: [0.402,0.598]

case 2

in: [0.9,50,1.645]

expected: [0.8302085606968878,0.9697914393031123]

case 3

in: [0,10,1.96]

expected: [0,0]

Starter codePython

def wald_interval_proportion(p_hat, n, z):
    # Your code here
    pass

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