Cross-Validation Score Std

Problem

Compute the population standard deviation of per-fold cross-validation scores.

Empty input or a single score returns 0.0.

Hint

Use the population variance (divide by n) and take the square root.

case 1

in: [[0.8,0.9,1]]

expected: 0.08164965809277258

case 2

in: [[1,1,1]]

expected: 0

case 3

in: [[0.5]]

expected: 0

case 4

in: [[]]

expected: 0

Starter codePython

def cv_score_std(fold_scores):
    # Your code here
    pass

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