title: Comparing Overlap in Pandas Columns
body: <p>So I have four columns in a pandas dataframe, column A, B, C and D. Column A contains 30 words, 18 of which are in column B. Column C contains either a 1 or 2 (keyboard response to column B words) and column D contains 1 or 2 also (the correct response). </p>
  
  <p>What I need to do is see the total correct for only the words where column A and B overlap. I understand how to compare the C and D columns to get the total correct once I have the correct dataframe, but I am having a hard time wrapping my head around comparing the overlap in A and B.   </p>