@article{ref1,
title="Statistics and Causality: Separated to Reunite—Commentary on Bryan Dowd's "Separated at Birth"",
journal="Health services research",
year="2011",
author="Pearl, Judea",
volume="46",
number="2",
pages="421-429",
abstract="<p>[Abstract unavailable]</p>",
language="",
issn="0017-9124",
doi="10.1111/j.1475-6773.2011.01243.x",
url="http://dx.doi.org/10.1111/j.1475-6773.2011.01243.x"
}