title: What is the difference between sum() and count() in pandas?
body: <p>Can you help me understand the difference between the statements mentioned below? Given that <code>Survived</code> column contains binary data (0,1), they give different answers:</p>
  
  <pre><code>df_train[df_train.Sex == 'female'].Survived.count()
  df_train[df_train.Sex == 'female'].Survived.sum()
  </code></pre>