出典:Wikipedia
出典:『Wikipedia』 (2011/04/18 21:39 UTC 版)
The Matthews correlation coefficient is used in machine learning as a measure of the quality of binary (two-class) classifications. 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. A coefficient of +1 represents a perfect prediction, 0 an average random prediction and −1 an inverse prediction. The statistic is also known as the phi coefficient. MCC is related to the chi-square statistic for a 2×2 contingency table