diff --git a/src/bin/cross_validation.py b/src/bin/cross_validation.py
index 0eca204..c081d75 100755
--- a/src/bin/cross_validation.py
+++ b/src/bin/cross_validation.py
@@ -27,7 +27,7 @@ import logging
 import datetime
 
 from config import Config
-from evaluation import CrossValidation, Precision, Recall, F1, Accuracy, SimpleAccuracy
+from evaluation import CrossValidation, Precision, Recall, F_score, FPR, Accuracy
 from recommender import Recommender
 from user import RandomPopcon,LocalSystem,PopconSystem
 
@@ -45,10 +45,10 @@ if __name__ == '__main__':
     metrics = []
     metrics.append(Precision())
     metrics.append(Recall())
-    metrics.append(F1())
+    metrics.append(F_score(0.5))
     metrics.append(Accuracy())
-    metrics.append(SimpleAccuracy())
-    validation = CrossValidation(0.9,10,rec,metrics,0.005)
+    metrics.append(FPR())
+    validation = CrossValidation(0.9,10,rec,metrics,1)
     validation.run(user)
     print validation
 
diff --git a/src/evaluation.py b/src/evaluation.py
index aacd8c1..af76d14 100644
--- a/src/evaluation.py
+++ b/src/evaluation.py
@@ -137,7 +137,8 @@ class FPR(Metric):
         """
         Compute metric.
         """
-        return float(len(evaluation.false_positive))/evaluation.true_negatives_len
+        return (float(len(evaluation.false_positive))/
+                evaluation.real_negative_len)
 
 class F_score(Metric):
     """
@@ -148,7 +149,7 @@ class F_score(Metric):
         """
         Set metric description.
         """
-        self.desc = "  F_score   "
+        self.desc = "  F(%.1f)  " % k
         self.k = k
 
     def run(self,evaluation):
@@ -254,12 +255,15 @@ class Evaluation:
         self.false_negative = [v[0] for v in self.real_relevant if not v[0] in
                                [w[0] for w in self.predicted_relevant]]
 
-        self.true_negatives_len = self.repository_size - len(self.real_relevant)
-        #logging.debug("TP: %d" % len(self.true_positive))
-        #logging.debug("FP: %d" % len(self.false_positive))
-        #logging.debug("FN: %d" % len(self.false_negative))
-        #logging.debug("Repo_size: %d" % self.repository_size)
-        #logging.debug("Relevant: %d" % len(self.real_relevant))
+        self.real_negative_len = self.repository_size-len(self.real_relevant)
+        self.true_negative_len = (self.real_negative_len-len(self.false_positive))
+        logging.debug("TP: %d" % len(self.true_positive))
+        logging.debug("FP: %d" % len(self.false_positive))
+        logging.debug("FN: %d" % len(self.false_negative))
+        logging.debug("TN: %d" % self.true_negative_len)
+        logging.debug("Repo_size: %d" % self.repository_size)
+        logging.debug("Relevant: %d" % len(self.real_relevant))
+        logging.debug("Irrelevant: %d" % self.real_negative_len)
 
     def run(self,metric):
         """
--
libgit2 0.21.2