(Springer Series in Statistics ) Paul R. Rosenbaum-Design of observational studies-Springer (2009).pdf

Springer Series in Statistics
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Paul R. Rosenbaum
Design of Observational
Studies
1 3
Paul R. Rosenbaum
Statistics Department
Wharton School
University of Pennsylvania
Philadelphia, PA 19104-6340
USA
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ISBN 978-1-4419-1212-1 e-ISBN 978-1-4419-1213-8
DOI -1-4419-1213-8
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For Judy
“Simplicity of form is not necessarily simplicity of experience.”
Robert Morris, writing about art.
“Simplicity is not a given. It is an achievement.”
William H. Gass, writing about literature.
“Simplicity . . . is a very important matter which must be constantly
borne in mind.”
Sir David Cox, writing about experiments.
Preface
An observational study is an empiric investigation of effects caused by treatments
when randomized experimentation is unethical or infeasible. The quality and
strength of evidence provided by an observational study is det