Negative Predictive Value from Counts

Problem

The negative predictive value is TN / (TN + FN), the probability a negative prediction is correct. Return 0.0 when the denominator is zero.

Given the counts, return the NPV.

Hint

Condition on the prediction being negative, not on the truth.

case 1

in: [9,1]

expected: 0.9

case 2

in: [2,2]

expected: 0.5

case 3

in: [0,5]

expected: 0

Starter codePython

def negative_predictive_value(tn, fn):
    # Your code here
    pass

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