Added MCC metric.

Tássia Camões Araújo
1 parent 336d03bf
Showing 1 changed file with 23 additions and 0 deletions Show diff stats
src/evaluation.py
@@ -140,6 +140,29 @@ class FPR(Metric):
         return (float(len(evaluation.false_positive))/
                 evaluation.real_negative_len)
  
+class MCC(Metric):
+    """
+    Matthews correlation coefficient.
+    """
+    def __init__(self):
+        """
+        Set metric description.
+        """
+        self.desc = "    MCC    "
+
+    def run(self,evaluation):
+        """
+        Compute metric.
+        """
+        VP = len(evaluation.true_positive)
+        FP = len(evaluation.false_positive)
+        FN = len(evaluation.false_negative)
+        VN = evaluation.true_negative_len
+        if (VP+FP)==0 or (VP+FN)==0 or (VN+FP)==0 or (VN+FN)==0:
+            return 0
+        MCC = (((VP*VN)-(FP*FN))/math.sqrt((VP+FP)*(VP+FN)*(VN+FP)*(VN+FN)))
+        return MCC
+
 class F_score(Metric):
     """
     Classification accuracy metric which correlates precision and recall into an
...	...	@@ -140,6 +140,29 @@ class FPR(Metric):
140	140	return (float(len(evaluation.false_positive))/
141	141	evaluation.real_negative_len)
142	142
	143	+class MCC(Metric):
	144	+ """
	145	+ Matthews correlation coefficient.
	146	+ """
	147	+ def __init__(self):
	148	+ """
	149	+ Set metric description.
	150	+ """
	151	+ self.desc = " MCC "
	152	+
	153	+ def run(self,evaluation):
	154	+ """
	155	+ Compute metric.
	156	+ """
	157	+ VP = len(evaluation.true_positive)
	158	+ FP = len(evaluation.false_positive)
	159	+ FN = len(evaluation.false_negative)
	160	+ VN = evaluation.true_negative_len
	161	+ if (VP+FP)==0 or (VP+FN)==0 or (VN+FP)==0 or (VN+FN)==0:
	162	+ return 0
	163	+ MCC = (((VPVN)-(FPFN))/math.sqrt((VP+FP)(VP+FN)(VN+FP)*(VN+FN)))
	164	+ return MCC
	165	+
143	166	class F_score(Metric):
144	167	"""
145	168	Classification accuracy metric which correlates precision and recall into an
...	...