J. Lockwood

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Genetic epidemiological methodologies, such as linkage analysis, often require accurate estimates of allele frequencies. When studies involve multiple sub-populations with different evolutionary histories, accurate estimates can be difficult to obtain because the number of subjects per sub-population tends to be limited. Given allele counts for a collection(More)
Traditional criteria for comparing alternative Bayesian hierarchical models, such as cross validation sums of squares, are inappropriate for non-standard data structures. More flexible cross validation criteria such as predictive densities facilitate effective evaluations across a broader range of data structures , but do so at the expense of introducing(More)
Repeated cross-sectional samples are common in national surveys of health like the National Health Interview Survey (NHIS). Because population health outcomes generally evolve slowly, pooling data across years can improve the precision of current-year annual estimates of disease prevalence and other health outcomes. Pooling over time is particularly(More)
The current framework for U.S. Environmental Protection Agency regulation of water quality in community drinking water supplies consists of sequential rules for either single contaminants or small groups of similar contaminants. For both substantive and pragmatic reasons, promulgating less frequent rules for larger contaminant classes may be desirable. Such(More)
Because it is well known that the power to measure differences between two groups is typically best with an even distribution of any given fixed sample size, great emphasis is often placed on exactly equal treatment and control allocations in evaluations of substance abuse interventions. Independent randomization of individuals (e.g., a "coin flip") when(More)
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