title: A Better Way to Calculate Odd Ratio in Pandas
body: <p>I have a dataframe counts1 which looks like:</p>
  
  <pre><code>Factor            w-statin  wo-statin
  AgeGroups Cancer                     
  0-5       No           108       6575
            Yes            0        223
  11-15     No             5       3669
            Yes            1        143
  16-20     No            28       6174
            Yes            1        395
  21-25     No            80       8173
            Yes            2        624
  26-30     No           110       9143
            Yes            2        968
  30-35     No           171       9046
            Yes            5       1225
  35-40     No           338       8883
            Yes           21       1475
  </code></pre>
  
  <p>I wanted to calculate the oddsratio (w-statin/wo-statin). I did it old style like I would do it in paper:</p>
  
  <pre><code>counts1['sumwwoStatin']= counts1['w-statin']+counts1['wo-statin']
  
  counts1['oddRatio']=((counts1['w-statin']/counts1['sumwwoStatin'])/(counts1['wo-statin']/counts1['sumwwoStatin']))
  </code></pre>
  
  <p>Is there a better way to calculate Odds-ratio, Relative risk, Contigency Table, &amp; Chi-Square Tests in Pandas, just like in R? Any suggestions are appreciated. Oh by the way, I forgot to mention how my csv looks like:</p>
  
  <pre><code>    Frequency Cancer     Factor AgeGroups
  0         223    Yes  wo-statin       0-5
  1         112    Yes  wo-statin      6-10
  2         143    Yes  wo-statin     11-15
  3         395    Yes  wo-statin     16-20
  4         624    Yes  wo-statin     21-25
  5         968    Yes  wo-statin     26-30
  6        1225    Yes  wo-statin     30-35
  7        1475    Yes  wo-statin     35-40
  8        2533    Yes  wo-statin     41-45
  9        4268    Yes  wo-statin     46-50
  10       5631    Yes  wo-statin     52-55
  11       6656    Yes  wo-statin     56-60
  12       7166    Yes  wo-statin     61-65
  13       8573    Yes  wo-statin     66-70
  14       8218    Yes  wo-statin     71-75
  15       4614    Yes  wo-statin     76-80
  16       1869    Yes  wo-statin     81-85
  17        699    Yes  wo-statin     86-90
  18        157    Yes  wo-statin     91-95
  19         31    Yes  wo-statin    96-100
  20          5    Yes  wo-statin      &gt;100
  21        108     No   w-statin       0-5
  22          6     No   w-statin      6-10
  23          5     No   w-statin     11-15
  24         28     No   w-statin     16-20
  25         80     No   w-statin     21-25
  26        110     No   w-statin     26-30
  27        171     No   w-statin     30-35
  28        338     No   w-statin     35-40
  29        782     No   w-statin     41-45
  ..
  </code></pre>