title: Accessing values in a Multiindex Series in Python
body: <p>I have a dataframe which I applied a groupby method call indexed off "Classification" and "Applying for FA?". </p>
  
  <pre><code>s = df.groupby("Classification")["Applying for FA?"].value_counts()
  </code></pre>
  
  <p>The following result is below</p>
  
  <pre><code>Classification  Applying for FA?
  FF              N                   172
                  Y                    26
  TR              N                     1
                  Y                     1
  Name: Applying for FA?, dtype: int64
  </code></pre>
  
  <p>Looking at the documentation for value_counts() it returns a series which is the object this information is stored. I want to access the particular values in the right column in order to do conditional probability. </p>
  
  <p>For example, if I need P(FF | N), then my result is 172/frequency of N. How to I access the proper value through the two column names. Basically I am looking for something like</p>
  
  <pre><code>s["FF"]["N"] ... returns 172
  s["FF"]["Y"] ... returns 26
  </code></pre>