The Matthews correlation coefficient is used in machine learning as a measure of the quality of binary (two-class) classifications, introduced by biochemist Brian W. Matthews in 1975. It takes into account true and false positives and negatives and is generally regarded as a balanced measure which can be used even if the classes are of very different sizes. The MCC is in essence a correlation coefficient between the observed and predicted binary classifications; it returns a value between −1 and +1.


---详见https://en.wikipedia.org/wiki/Matthews_correlation_coefficient#cite_note-Matthews1975-1


我想探讨的是这个公式是怎么构造出来的