title: How to get ROC curve for decision tree?
body: <p>I am trying to find <em>ROC curve</em> and <em>AUROC curve</em> for decision tree. My code was something like</p>
  
  <pre><code>clf.fit(x,y)
  y_score = clf.fit(x,y).decision_function(test[col])
  pred = clf.predict_proba(test[col])
  print(sklearn.metrics.roc_auc_score(actual,y_score))
  fpr,tpr,thre = sklearn.metrics.roc_curve(actual,y_score)
  </code></pre>
  
  <p>output:</p>
  
  <pre><code> Error()
  'DecisionTreeClassifier' object has no attribute 'decision_function'
  </code></pre>
  
  <p>basically, the error is coming up while finding the <code>y_score</code>. Please explain what is <code>y_score</code> and how to solve this problem?</p>