Jump to content


  • Content Count

  • Joined

  • Last visited

Community Reputation

0 Neutral

About Robai

  • Rank
  • Birthday 04/16/1974

Previous Fields

  • Languages
    (X)HTML, CSS, JavaScript, PHP, MySQL.

Contact Methods

  • Website URL
  • ICQ

Profile Information

  • Location
    Lithuania, Vilnius
  • Interests
    Math:<br />1. Group Theory.<br />2. Mathematical Statistics, Probability Theory, Paradoxes.<br />3. Polynomial Algebra.

About Me

Simpson's paradox

A doctor has performed clinical trials to determine the relative efficacies of two drugs, with the following results:



Which drug is better?

Here are two conflicting responses:

  1. Drug I was given to 2020 people, of whom 219 were cured. The success rate was 219/2020, which is much smaller than the corresponding figure, 1010/2200, for drug II.
    Therefore drug II is better than drug I.
  2. Amongst women the success rates of drugs are 200/2000 and 10/200, and amongst men 19/20 and 1000/2000.
    Drug I wins in both cases.

Taken from:

G.Grimmett, D.Stirzaker, Probability and Random Processes, 2001.

  • Create New...