Sentences to ponder…

Notably, easy-to-reach women are happier than easy-to-reach men, but hard-to-reach men are happier than hard-to-reach women, and conclusions of a survey could reverse with more attempted calls.

That is Ori Heffetz and Matthew Rabin, in the new AER.  An ungated version is here.  Understandably, the authors are worried about potential subject selection biases in studies of self-reported happiness.