3 ms·
Interesting, I only ever heard of Simpson's paradox in the context of comparing overall averages versus subgroup averages. I guess this paradox could then be t
by caddemon 6y ago
Interesting, I only ever heard of Simpson's paradox in the context of comparing overall averages versus subgroup averages.
I guess this paradox could then be thought of as a special case of Simpson's paradox? Since the out group will exclude people with both traits there should also be a negative correlation there, which disappears in the overall population. But in Berkson's case it seems they're implying the subgroup correlation is spurious whereas with Simpson's it could go either way.
- kgwgk 6y ago> Since the out group will exclude people with both traits there should also be a negative correlation there Not necessarily. Imagine the traits are distributed uniformly and independently in [-1 1]. There is no correlation: ****** ****** ****** ****** ****** ****** If you select people with at least one positive trait you will find negative correlation in the group + but the correlation will still be zero in the group -. ++++++ ++++++ ++++++ ---+++ ---+++ ---+++
- caddemon 6y agoMakes sense, I was picturing more of a diagonal boundary but you're right the paradox doesn't specify the shape of the boundary. Thanks!