Hi all,
We hope you can join us this Wednesday, November 14, 2012 for the Applied
Statistics Workshop. Cassandra Wolos
Pattanayak<http://www.people.fas.harvard.edu/~wolos/Site/Home.html>ml>,
a College Fellow from the Department of Statistics at Harvard University,
will give a presentation entitled "A Potential Outcomes, and Typically More
Powerful, Alternative to 'Cochran-Mantel-Haenszel'". A light lunch will be
served at 12 pm and the talk will begin at 12.15.
Abstract:
In studies of public health, outcome measures such as
the odds ratio, rate
ratio, or efficacy are often estimated across strata to assess the overall
effect of active treatment versus control treatment. Patients may be
partitioned into such strata or blocks by experimental design, or, in
non-randomized studies, patients may be partitioned into subclasses based
on key covariates or estimated propensity scores to improve observed
covariate balance across treatment groups. In finite samples, there exist
tests and intervals for these estimands that can be more powerful than
tests and intervals created with Cochran-Mantel-Haenszel or analogous
procedures . The proposed methods multiply impute missing potential
outcomes within the Rubin Causal Model so that estimands can be directly
estimated. The assumptions underlying these typically more powerful methods
are appropriate in many circumstances, especially when the strata are based
on covariates highly predictive of treatment decisions and outcomes. When
used to draw inferences about a population from which the patients in the
study are considered a random sample, and the sample is large, these
methods are extremely similar to the classical methods. The proposed
approach is particularly relevant when assessing the safety of a new
treatment relative to a standard one because, under typical conditions, the
tests are more powerful and the intervals are shorter, thereby detecting
smaller differences.
An up-to-date schedule for the workshop is available at
http://www.iq.harvard.edu/events/node/1208.
Best,
Konstantin
--
Konstantin Kashin
Ph.D. Candidate in Government
Harvard University
Mobile: 978-844-0538
E-mail: kkashin(a)fas.harvard.edu
Site:
http://www.konstantinkashin.com/<http://people.fas.harvard.edu/%7Ekkashi…