Spatial regression and spillover effects in cluster randomized trials with count outcomes.

abstract：:An estimator proposed by Greenland and Holland (1991, Biometrics 47, 319-322) for a standardized risk difference parameter is shown to be a maximum likelihood estimator if the consistent estimator of the common odds ratio is appropriately chosen. The statistical problem under consideration is reparameterized. Likeliho...

journal_title：Biometrics

authors： Yu KF

更新日期：1992-09-01 00:00:00

abstract：:In the area of ecological research the study of species diversity of a community or population seems to have been fully developed. However, the problem of how the distributions and expectations of the sample diversity indices are affected by the population diversity has received little attention. In this paper we show...

journal_title：Biometrics

authors： Tong YL

更新日期：1983-12-01 00:00:00

abstract：:This article introduces an original methodology based on empirical likelihood, which aims at combining different food contamination and consumption surveys to provide risk managers with a risk measure, taking into account all the available information. This risk index is defined as the probability that exposure to a c...

journal_title：Biometrics

authors： Crépet A,Harari-Kermadec H,Tressou J

更新日期：2009-03-01 00:00:00

abstract：:In this study we are concerned with the construction of confidence intervals for the conditional probability of misallocation associated with Anderson's classification statistics, W. The available methods of computing confidence intervals for the conditional probability are not satisfactory in practice, mainly because...

journal_title：Biometrics

authors： McLachlan GJ

更新日期：1975-03-01 00:00:00

abstract：:We consider a capture-recapture model in which capture probabilities vary with time and with behavioral response. Two inference procedures are developed under the assumption that recapture probabilities bear a constant relationship to initial capture probabilities. These two procedures are the maximum likelihood metho...

journal_title：Biometrics

authors： Chao A,Chu W,Hsu CH

更新日期：2000-06-01 00:00:00

abstract：:A stochastic model is presented for the analysis of incomplete repeated-measures experiments. The general linear model is used to relate the response measures to other variables which are thought to account for inherent variation; an autoregressive moving average (ARMA) time series representation is used to model dist...

journal_title：Biometrics

authors： Rochon J,Helms RW

更新日期：1989-03-01 00:00:00

abstract：:A likelihood ratio statistic is proposed for testing goodness of fit with grouped data which are subject to random right censoring. It is shown that, under appropriate conditions, this statistic has an asymptotic chi-square distribution which is non-central under contiguous alternatives. A formula is given for the non...

journal_title：Biometrics

authors： Turnbull BW,Weiss L

更新日期：1978-09-01 00:00:00

abstract：:In the context of group testing screening, McMahan, Tebbs, and Bilder (2012, Biometrics 68, 287-296) proposed a two-stage procedure in a heterogenous population in the presence of misclassification. In earlier work published in Biometrics, Kim, Hudgens, Dreyfuss, Westreich, and Pilcher (2007, Biometrics 63, 1152-1162)...

journal_title：Biometrics

authors： Malinovsky Y,Albert PS,Roy A

更新日期：2016-03-01 00:00:00

abstract：:A time-dependent measure, termed the rate ratio, was proposed to assess the local dependence between two types of recurrent event processes in one-sample settings. However, the one-sample work does not consider modeling the dependence by covariates such as subject characteristics and treatments received. The focus of ...

journal_title：Biometrics

authors： Ning J,Cai C,Chen Y,Huang X,Wang MC

更新日期：2020-12-01 00:00:00

abstract：:In clinical studies, longitudinal biomarkers are often used to monitor disease progression and failure time. Joint modeling of longitudinal and survival data has certain advantages and has emerged as an effective way to mutually enhance information. Typically, a parametric longitudinal model is assumed to facilitate t...

journal_title：Biometrics

authors： Ding J,Wang JL

更新日期：2008-06-01 00:00:00

abstract：:Epidemiological studies involving biomarkers are often hindered by prohibitively expensive laboratory tests. Strategically pooling specimens prior to performing these lab assays has been shown to effectively reduce cost with minimal information loss in a logistic regression setting. When the goal is to perform regress...

journal_title：Biometrics

authors： Mitchell EM,Lyles RH,Manatunga AK,Danaher M,Perkins NJ,Schisterman EF

更新日期：2014-03-01 00:00:00

abstract：:For patients on dialysis, hospitalizations remain a major risk factor for mortality and morbidity. We use data from a large national database, United States Renal Data System, to model time-varying effects of hospitalization risk factors as functions of time since initiation of dialysis. To account for the three-level...

journal_title：Biometrics

authors： Li Y,Nguyen DV,Kürüm E,Rhee CM,Chen Y,Kalantar-Zadeh K,Şentürk D

更新日期：2020-09-01 00:00:00

abstract：:A common measure in clinical trials and epidemiologic studies is the number of events such as seizures, hospitalizations, or bouts of disease. Frequently, a binary measure of severity for each event is available but is not incorporated in the analysis. This paper proposes methodology for jointly modeling the number of...

journal_title：Biometrics

authors： Albert PS,Follmann DA,Barnhart HX

更新日期：1997-09-01 00:00:00

abstract：:We suggest an estimator for the proportional odds cumulative incidence model for competing risks data. The key advantage of this model is that the regression parameters have the simple and useful odds ratio interpretation. The model has been considered by many authors, but it is rarely used in practice due to the lack...

journal_title：Biometrics

authors： Eriksson F,Li J,Scheike T,Zhang MJ

更新日期：2015-09-01 00:00:00

abstract：:In this paper we offer a mathematical definition for the probability of causation that formalizes the legal and ordinary-language meaning of the term. We show that, under this definition, even the average probability of causation among exposed cases is not identifiable from epidemiologic data. This is because the prob...

journal_title：Biometrics

authors： Robins J,Greenland S

更新日期：1989-12-01 00:00:00

abstract：:Development of HIV resistance mutations is a major cause for failure of antiretroviral treatment. This article proposes a method for jointly modeling the processes of viral genetic changes and treatment failure. Because the viral genome is measured with uncertainty, a hidden Markov model is used to fit the viral genet...

journal_title：Biometrics

authors： Hu C,De Gruttola V

更新日期：2007-03-01 00:00:00

abstract：:When testing the null hypothesis that treatment arm-specific survival-time distributions are equal, the log-rank test is asymptotically valid when the distribution of time to censoring is conditionally independent of randomized treatment group given survival time. We introduce a test of the null hypothesis for use whe...

journal_title：Biometrics

authors： DiRienzo AG

更新日期：2003-09-01 00:00:00

abstract：:Using genetic recombination data to make inferences about chiasmata on the tetrad during meiosis is a classic problem dating back to Weinstein's paper in 1936 (Genetics 21, 155-199). In the last few years, Weinstein's methods have been revived and applied to new problems, but a number of important statistical issues r...

journal_title：Biometrics

authors： Yu K,Feingold E

更新日期：2002-06-01 00:00:00

abstract：:We describe a Bayesian quantile regression model that uses a confirmatory factor structure for part of the design matrix. This model is appropriate when the covariates are indicators of scientifically determined latent factors, and it is these latent factors that analysts seek to include as predictors in the quantile ...

journal_title：Biometrics

authors： Burgette LF,Reiter JP

更新日期：2012-03-01 00:00:00

abstract：:Whenever inference for variance components is required, the choice between one-sided and two-sided tests is crucial. This choice is usually driven by whether or not negative variance components are permitted. For two-sided tests, classical inferential procedures can be followed, based on likelihood ratios, score stati...

journal_title：Biometrics

authors： Verbeke G,Molenberghs G

更新日期：2003-06-01 00:00:00

abstract：:In the calibration problem, the need to construct a confidence interval to estimate the unknown chi 0 arises when the null hypothesis of zero slope is rejected. Otherwise, the resulting confidence interval will be infinite to reflect the fact that the slope of the regression line may be zero. Under the condition of re...

journal_title：Biometrics

authors： Lee JJ

更新日期：1991-12-01 00:00:00

abstract：:Understanding HIV incidence, the rate at which new infections occur in populations, is critical for tracking and surveillance of the epidemic. In this article, we derive methods for determining sample sizes for cross-sectional surveys to estimate incidence with sufficient precision. We further show how to specify samp...

journal_title：Biometrics

authors： Konikoff J,Brookmeyer R

更新日期：2015-12-01 00:00:00

abstract：:Some failure time data come from a population that consists of some subjects who are susceptible to and others who are nonsusceptible to the event of interest. The data typically have heavy censoring at the end of the follow-up period, and a standard survival analysis would not always be appropriate. In such situation...

journal_title：Biometrics

authors： Sy JP,Taylor JM

更新日期：2000-03-01 00:00:00

abstract：:Three properties of interest in bioavailability studies using compartmental models are the area under the concentration curve, the maximum concentration, and the time to maximum concentration. Methods are described for finding designs that minimize the variance of the estimates of these quantities in such a model. The...

journal_title：Biometrics

authors： Atkinson AC,Chaloner K,Herzberg AM,Juritz J

更新日期：1993-06-01 00:00:00

abstract：:In biomedical cohort studies for assessing the association between an outcome variable and a set of covariates, usually, some covariates can only be measured on a subgroup of study subjects. An important design question is-which subjects to select into the subgroup to increase statistical efficiency. When the outcome ...

journal_title：Biometrics

authors： Wang L,Williams ML,Chen Y,Chen J

更新日期：2020-03-01 00:00:00

abstract：:We propose a likelihood-based test for comparing the means of two or more log-normal distributions, with possibly unequal variances. A modification to the likelihood ratio test is needed when sample sizes are small. The performance of the proposed procedures is compared with the F-ratio test using Monte Carlo simulati...

journal_title：Biometrics

authors： Gill PS

更新日期：2004-06-01 00:00:00

abstract：:In this article, we develop new methods for estimating average treatment effects in observational studies, in settings with more than two treatment levels, assuming unconfoundedness given pretreatment variables. We emphasize propensity score subclassification and matching methods which have been among the most popular...

journal_title：Biometrics

authors： Yang S,Imbens GW,Cui Z,Faries DE,Kadziola Z

更新日期：2016-12-01 00:00:00

abstract：:Interval-censored failure time data occur in many fields such as demography, economics, medical research, and reliability and many inference procedures on them have been developed (Sun, 2006; Chen, Sun, and Peace, 2012). However, most of the existing approaches assume that the mechanism that yields interval censoring ...

journal_title：Biometrics

authors： Wang P,Zhao H,Sun J

更新日期：2016-12-01 00:00:00

abstract：:An adjusted rank correlation test is proposed as a technique for identifying publication bias in a meta-analysis, and its operating characteristics are evaluated via simulations. The test statistic is a direct statistical analogue of the popular "funnel-graph." The number of component studies in the meta-analysis, the...

journal_title：Biometrics

authors： Begg CB,Mazumdar M

更新日期：1994-12-01 00:00:00

abstract：:In epidemiologic studies, subjects are often misclassified as to their level of exposure. Ignoring this misclassification error in the analysis introduces bias in the estimates of certain parameters and invalidates many hypothesis tests. For situations in which there is misclassification of exposure in a follow-up stu...

journal_title：Biometrics

authors： Reade-Christopher SJ,Kupper LL

更新日期：1991-06-01 00:00:00