The DOI matches its Crossref record; 12 of the 12 references it cites were found in a registry or an index.
Biased estimates of treatment effect in randomized experiments with nonlinear regressions and omitted covariates
Abstract
Certain important nonlinear regression models lead to biased estimates of treatment effect, even in randomized experiments, if needed covariates are omitted. The asymptotic bias is determined both for estimates based on the method of moments and for maximum likelihood estimates. The asymptotic bias from omitting covariates is shown to be zero if the regression of the response variable on treatment and covariates is linear or exponential, and, in regular cases, this is a necessary condition for zero bias. Many commonly used models do have such exponential regressions; thus randomization ensures unbiased treatment estimates in a large number of important nonlinear models. For moderately censored exponential survival data, analysis with the exponential survival model yields less biased estimates of treatment effect than analysis with the proportional hazards model of Cox, if needed covariates are omitted. Simulations confirm that calculations of asymptotic bias are in excellent agreement with the bias observed in experiments of modest size.
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Cites
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Singer, J. D., & Willett, J. B. (2003) · doi:10.1093/acprof:oso/9780195152968.001.0001 · Cited by 10,647
Austin, P. C. (2009) · Statistics in Medicine · doi:10.1002/sim.3697 · Cited by 6,758
Logistic Regression: Why We Cannot Do What We Think We Can Do, and What We Can Do About It
Mood, C. (2010) · European Sociological Review · doi:10.1093/esr/jcp006 · Cited by 3,158
Evaluating non-randomised intervention studies
Deeks, J., Dinnes, J., D'Amico, R., Sowden, A., Sakarovitch, C., Song, F., Petticrew, M., & Altman, D. (2003) · Health Technology Assessment · doi:10.3310/hta7270 · Cited by 2,907
Metadata
- Authors
- GAIL, M. H., WIEAND, S., & PIANTADOSI, S.
- Venue
- Biometrika
- Publisher
- Oxford University Press (OUP)
- Published
- 1984
- Volume
- 71
- Issue
- 3
- Pages
- 431-444
- ISSN
- 0006-3444 (ISSN-L)
- 1464-3510
- OpenAlex
- W2006623746
- Cited by
- 698
- References
- 12
- FWCI
- 3.49
- Type
- journal article
- Language
- en
- Open access
- closed
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