The post should have mentioned selection bias, specifically self-selection bias: http://en.wikipedia.org/wiki/Self-selection http://en.wikipedia.org/wiki/Self-

The post should have mentioned selection bias, specifically self-selection bias: http://en.wikipedia.org/wiki/Self-selection http://en.wikipedia.org/wiki/Self-selection which leads to some relevant literature: http://www.allacademic.com/meta/p362803_index.html http://www.allacademic.com/meta/p362803_index.html