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Full-Text Articles in Medicine and Health Sciences
A Bayesian Analysis Involving Colonic Crypt Structure And Coordinated Response To Carcinogens Incorporating Missing Crypts, Jeffrey S. Morris, Naisyin Wang, Joanne R. Lupton, Robert S. Chapkin, Nancy D. Turner, Mee-Young Hong, Raymond J. Carroll
A Bayesian Analysis Involving Colonic Crypt Structure And Coordinated Response To Carcinogens Incorporating Missing Crypts, Jeffrey S. Morris, Naisyin Wang, Joanne R. Lupton, Robert S. Chapkin, Nancy D. Turner, Mee-Young Hong, Raymond J. Carroll
Jeffrey S. Morris
This paper is concerned with modeling the architecture of colonic crypts and the implications of this modeling for understanding possible coordinated response of carcinogen–induced DNA damage between various regions of the colon. The methods we develop to address these two issues are applied to a particular important example in colon carcinogenesis. We cast the problem as an unusual and not previously studied hierarchical mixed-effects model characterized by completely missing covariates in units at a structurally base level, except for some randomly selected units. Information concerning the missing covariates is available through certain known ordering constraints and surrogate measures. Our methods …
The Blups Are Not “Best” When It Comes To Bootstrapping, Jeffrey S. Morris
The Blups Are Not “Best” When It Comes To Bootstrapping, Jeffrey S. Morris
Jeffrey S. Morris
In the setting of mixed models, some researchers may construct a semiparametric bootstrap by sampling from the best linear unbiased predictor residuals. This paper demonstrates both mathematically and by simulation that such a bootstrap will consistently underestimate the variation in the data in finite samples.