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Accession Number ADA578366
Title Comments on 'Surrogates measures and consistent surrogates' (by Tyler VanderWeele).
Publication Date Mar 2013
Media Count 5p
Personal Author J. Pearl
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.
Keywords Causal analysis
Causal inference
Linear models
Statistical inference
Surrogate paradox

 
Source Agency Non Paid ADAS
NTIS Subject Category 72F - Statistical Analysis
Corporate Author California Univ., Los Angeles. Dept. of Computer Science.
Document Type Technical report
Title Note Technical rept.
NTIS Issue Number 1321
Contract Number N00014-13-1-0153 N00014-10-1-0933

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