This page is for discussion of "observer" or "confirmation" bias.

A couple of recent articles identify and discuss a number of even subtler biases one has to watch out against:

Jonah Lehrer, New Yorker, 12/13/2010, 86(40) "The truth wears off"

John Ioannidis, "Why Most Published Research Findings Are False" (the title is intentionally provocative, but results are worrying).