diff --git a/include/graph/preprocessing.h b/include/graph/preprocessing.h
index 63b7373..70dedb1 100644
--- a/include/graph/preprocessing.h
+++ b/include/graph/preprocessing.h
@@ -19,6 +19,7 @@ class LabelIndex {
   virtual void Insert(NodeId node, std::vector<Label> label) = 0;
   virtual void Load(const std::string& path) = 0;
   virtual double PrecisionScore(torch::Tensor y_pred, torch::Tensor y_true) const = 0;
+  virtual double F1Score(torch::Tensor y_pred, torch::Tensor y_true, const std::string& option) const = 0;
 };
 
 class MultiLabelBinarizer: public LabelIndex {
@@ -77,6 +78,10 @@ class MultiLabelBinarizer: public LabelIndex {
 
   }
 
+  virtual double F1Score(torch::Tensor y_pred, torch::Tensor y_true, const std::string& option) {
+
+  }
+
  protected:
   std::vector<std::vector<Label>> labels_;
   IndexLookupTable index_;
@@ -125,6 +130,59 @@ class MultiLabelIndex : public MultiLabelBinarizer {
     return n_right * 1.0 / n_total;
   }
 
+  virtual double F1Score(torch::Tensor y_pred, torch::Tensor y_true, const std::string& option) const override {
+    int n_class = y_pred.size(1);
+    auto y = y_pred.argmax(1).to(torch::TensorOptions().dtype(torch::kInt64));
+    int64_t true_negatives = 0;
+    int64_t true_positives = 0;
+    int64_t false_negatives = 0;
+    int64_t false_positives = 0;
+    double precision = 0;
+    double recall = 0;
+    double average_f1score = 0;
+    for (int64_t i = 0; i < n_class; i++)
+    {
+      auto this_class_mask = torch::full(y.sizes(), i, torch::TensorOptions().dtype(torch::kInt64));
+      auto positive_label_mask = y_true.eq(this_class_mask).to(torch::TensorOptions().dtype(torch::kInt64));
+      auto mask = torch::ones(positive_label_mask.sizes(), torch::TensorOptions().dtype(torch::kInt64));
+      auto negative_label_mask = torch::sub(mask, positive_label_mask);
+
+      auto correct_null_predictions = torch::mul(torch::ne(y, this_class_mask).to(torch::TensorOptions().dtype(torch::kInt64)), negative_label_mask);
+      double tmp_true_negatives =  torch::mul(correct_null_predictions, mask).sum().item().toInt();
+      true_negatives += tmp_true_negatives;
+      //std::cout << "true_neg=" << tmp_true_negatives << std::endl;
+
+      auto correct_non_null_predictions = torch::mul(torch::eq(y, this_class_mask).to(torch::TensorOptions().dtype(torch::kInt64)), positive_label_mask);
+      double tmp_true_positives =  torch::mul(correct_non_null_predictions, mask).sum().item().toInt();
+      true_positives += tmp_true_positives;
+      //std::cout << "true_pos=" << tmp_true_positives << std::endl;
+
+      auto incorrect_null_predictions = torch::mul(torch::ne(y, this_class_mask).to(torch::TensorOptions().dtype(torch::kInt64)), positive_label_mask);
+      double tmp_false_negatives =  torch::mul(incorrect_null_predictions, mask).sum().item().toInt();
+      false_negatives += tmp_false_negatives;
+      //std::cout << "false_neg=" << tmp_false_negatives << std::endl;
+
+      auto incorrect_non_null_predictions = torch::mul(torch::eq(y, this_class_mask).to(torch::TensorOptions().dtype(torch::kInt64)), negative_label_mask);
+      double tmp_false_positives =  torch::mul(incorrect_non_null_predictions, mask).sum().item().toInt();
+      false_positives += tmp_false_positives;
+      //std::cout << "false_pos=" << tmp_false_positives << std::endl;
+
+      if (option == "macro") {
+        precision = double(tmp_true_positives) / (tmp_true_positives + tmp_false_positives + 1e-13);
+        recall = double(tmp_true_positives) / (tmp_true_positives + tmp_false_negatives + 1e-13);
+        average_f1score +=  2 * recall * precision / (recall + precision + 1e-13);
+      }
+    }
+    if (option == "macro") {
+      return average_f1score;
+    }
+    else {
+      precision = double(true_positives) / (true_positives + false_positives + 1e-13);
+      recall = double(true_positives) / (true_positives + false_negatives + 1e-13);
+      return  2 * recall * precision / (recall + precision + 1e-13);
+    }
+  }
+
  private:
   Label current_class_;
 };
@@ -174,6 +232,58 @@ class SingleLabelIndex : public LabelIndex {
     return n_right * 1.0 / n_total;
   }
 
+  virtual double F1Score(torch::Tensor y_pred, torch::Tensor y_true, const std::string& option) const override {
+    int n_class = y_pred.size(1);
+    auto y = y_pred.argmax(1).to(torch::TensorOptions().dtype(torch::kInt64));
+    int64_t true_negatives = 0;
+    int64_t true_positives = 0;
+    int64_t false_negatives = 0;
+    int64_t false_positives = 0;
+    double precision = 0;
+    double recall = 0;
+    double average_f1score = 0;
+    for (int64_t i = 0; i < n_class; i++)
+    {
+      auto this_class_mask = torch::full(y.sizes(), i, torch::TensorOptions().dtype(torch::kInt64));
+      auto positive_label_mask = y_true.eq(this_class_mask).to(torch::TensorOptions().dtype(torch::kInt64));
+      auto mask = torch::ones(positive_label_mask.sizes(), torch::TensorOptions().dtype(torch::kInt64));
+      auto negative_label_mask = torch::sub(mask, positive_label_mask);
+
+      auto correct_null_predictions = torch::mul(torch::ne(y, this_class_mask).to(torch::TensorOptions().dtype(torch::kInt64)), negative_label_mask);
+      double tmp_true_negatives =  torch::mul(correct_null_predictions, mask).sum().item().toInt();
+      true_negatives += tmp_true_negatives;
+      //std::cout << "true_neg=" << tmp_true_negatives << std::endl;
+
+      auto correct_non_null_predictions = torch::mul(torch::eq(y, this_class_mask).to(torch::TensorOptions().dtype(torch::kInt64)), positive_label_mask);
+      double tmp_true_positives =  torch::mul(correct_non_null_predictions, mask).sum().item().toInt();
+      true_positives += tmp_true_positives;
+      //std::cout << "true_pos=" << tmp_true_positives << std::endl;
+
+      auto incorrect_null_predictions = torch::mul(torch::ne(y, this_class_mask).to(torch::TensorOptions().dtype(torch::kInt64)), positive_label_mask);
+      double tmp_false_negatives =  torch::mul(incorrect_null_predictions, mask).sum().item().toInt();
+      false_negatives += tmp_false_negatives;
+      //std::cout << "false_neg=" << tmp_false_negatives << std::endl;
+
+      auto incorrect_non_null_predictions = torch::mul(torch::eq(y, this_class_mask).to(torch::TensorOptions().dtype(torch::kInt64)), negative_label_mask);
+      double tmp_false_positives =  torch::mul(incorrect_non_null_predictions, mask).sum().item().toInt();
+      false_positives += tmp_false_positives;
+      //std::cout << "false_pos=" << tmp_false_positives << std::endl;
+
+      if (option == "macro") {
+        precision = double(tmp_true_positives) / (tmp_true_positives + tmp_false_positives + 1e-13);
+        recall = double(tmp_true_positives) / (tmp_true_positives + tmp_false_negatives + 1e-13);
+        average_f1score +=  2 * recall * precision / (recall + precision + 1e-13);
+      }
+    }
+    if (option == "macro") {
+      return average_f1score;
+    }
+    else {
+      precision = double(true_positives) / (true_positives + false_positives + 1e-13);
+      recall = double(true_positives) / (true_positives + false_negatives + 1e-13);
+      return  2 * recall * precision / (recall + precision + 1e-13);
+    }
+  }
 
  private:
   std::unordered_map<NodeId, Label> labels_;