Accession Number : ADA578366


Title :   Comments on Surrogates measures and consistent surrogates (by Tyler VanderWeele)


Descriptive Note : Technical rept.


Corporate Author : CALIFORNIA UNIV LOS ANGELES DEPT OF COMPUTER SCIENCE


Personal Author(s) : Pearl, Judea


Full Text : http://www.dtic.mil/dtic/tr/fulltext/u2/a578366.pdf


Report Date : Mar 2013


Pagination or Media Count : 5


Abstract : I commend Professor VanderWeele for providing a lucid description of the surrogate paradox and, through it, a comprehensive discussion of the current state of thinking about surrogate endpoints, their function in experimental studies, and the various approaches devised to give them formal underpinnings. The first question that came to mind in reading VanderWeele's paper was: can we explain the phenomenon in simple terms, divorced from the technical vocabulary that was devised to formulate notions such as indirect effect, principled strata, proportion-mediated, and perhaps others? My second question was: If we take the negation of the surrogate paradox as a criterion for good surrogate, why can't we create a new, formal definition of surrogacy that (1) will automatically avoid the paradox and (2) will settle, once for all, the disputes (among theoreticians) as to what approach is best for defining surrogates (Joffe and Green, 2009, pp. 530-538; Pearl, 2011). In thinking about these two questions, I came across a simple way of explaining how the paradox comes about and, indirectly, why the requirement of avoiding the paradox could not, in itself, constitute a satisfactory definition of surrogacy.


Descriptors :   *STATISTICAL INFERENCE


Subject Categories : Statistics and Probability


Distribution Statement : APPROVED FOR PUBLIC RELEASE