Cluster Sampling Variance

Problem

Return the cluster sampling variance of the mean estimator sum((mean_j - grand)^2) / (M*(M-1)) for M cluster means. Return 0.0 when fewer than two clusters are given.

Hint

Clusters act as the independent units.

Test cases

case 1

in: [[1,2,3,4]]

expected: 0.4166666666666667

case 2

in: [[5,5,5]]

expected: 0

case 3

in: [[1,5]]

expected: 4

case 4

in: [[1]]

expected: 0

case 5

in: [[]]

expected: 0

Starter codePython

def cluster_sampling_variance(cluster_means):
    # Your code here
    pass

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