I would add to the list 'revealed preference' '... an economic theory of consumption behavior which asserts that the best way to measure consumer preferences i

I would add to the list 'revealed preference' '... an economic theory of consumption behavior which asserts that the best way to measure consumer preferences is to observe their purchasing behavior. Revealed preference theory works on the assumption that consumers have considered a set of alternatives before making a purchasing decision. Thus, given that a consumer chooses one option out of the set, this option must be the preferred option' http://www.investopedia.com/terms/r/revealed-preference.asp http://www.investopedia.com/terms/r/revealed-preference.asp In other words "observe their actions, not their words"