Matthews Correlation Coefficient

Problem

Compute the Matthews correlation coefficient for binary labels with positive class 1: (TP*TN - FP*FN) / sqrt((TP+FP)*(TP+FN)*(TN+FP)*(TN+FN)).

Return 0.0 when the denominator is zero. Empty input returns 0.0.

Hint

The numerator compares correct and incorrect counts; +1 means perfect agreement and -1 total disagreement.

case 1

in: [[1,1,0,0],[1,1,0,0]]

expected: 1

case 2

in: [[1,1,0,0],[0,0,1,1]]

expected: -1

case 3

in: [[1,1,1],[1,1,1]]

expected: 0

case 4

in: [[1,0,1,0,1],[1,1,0,1,0]]

expected: -0.6666666666666666

Starter codePython

import math
def matthews_corrcoef(y_true, y_pred):
    # Your code here
    pass

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