Alternative hypotheses for the effects of drugs in small-scale clinical studies.

abstract：:The standard approach to inference for random effects meta-analysis relies on approximating the null distribution of a test statistic by a standard normal distribution. This approximation is asymptotic on k, the number of studies, and can be substantially in error in medical meta-analyses, which often have only a few ...

journal_title：Biometrics

authors： Follmann DA,Proschan MA

更新日期：1999-09-01 00:00:00

abstract：:The class of admissible tests for Hardy-Weinberg equilibrium in a multi-allelic system is characterized. The standard goodness-of-fit chi-square tests is shown to be admissible for systems of two or more alleles. The conditional probability distribution required to determine the exact significance level of this test i...

journal_title：Biometrics

authors： Ledwina T,Gnot S

更新日期：1980-03-01 00:00:00

abstract：:There has been great interest in developing nonlinear structural equation models and associated statistical inference procedures, including estimation and model selection methods. In this paper a general semiparametric structural equation model (SSEM) is developed in which the structural equation is composed of nonpar...

journal_title：Biometrics

authors： Guo R,Zhu H,Chow SM,Ibrahim JG

更新日期：2012-06-01 00:00:00

abstract：:Dilution assays to determine solute concentration have found wide use in biomedical research. Many dilution assays return imprecise concentration estimates because they are only done to orders of magnitude. Previous statistical work has focused on how to design efficient experiments that can return more precise estima...

journal_title：Biometrics

authors： Ferguson JM,Miura TA,Miller CR

更新日期：2019-09-01 00:00:00

abstract：:Suppose that a heterogeneous group of individuals is followed over time and that each individual can be in state 0 or state 1 at each time point. The sequence of states is assumed to follow a binary Markov chain. In this paper we model the transition probabilities for the 0 to 0 and 1 to 0 transitions by two logistic ...

journal_title：Biometrics

authors： Muenz LR,Rubinstein LV

更新日期：1985-03-01 00:00:00

abstract：:The distribution of health care payments to insurance plans has substantial consequences for social policy. Risk adjustment formulas predict spending in health insurance markets in order to provide fair benefits and health care coverage for all enrollees, regardless of their health status. Unfortunately, current risk ...

journal_title：Biometrics

authors： Zink A,Rose S

更新日期：2020-09-01 00:00:00

abstract：:The search for an optimal dose of a drug has been investigated in a sequential setting to ensure the safety level by Eichhorn and Zacks (1973, Journal of the American Statistical Association 68, 594-598; 1981, Communications in Statistics--Theory and Methods A10, 931-953), Eichhorn (1974, Communications in Statistics ...

journal_title：Biometrics

authors： Shih WJ

更新日期：1989-06-01 00:00:00

abstract：:Estimating the number of clusters in a data set is a crucial step in cluster analysis. In this article, motivated by the gap method (Tibshirani, Walther, and Hastie, 2001, Journal of the Royal Statistical Society B63, 411-423), we propose the weighted gap and the difference of difference-weighted (DD-weighted) gap met...

journal_title：Biometrics

authors： Yan M,Ye K

更新日期：2007-12-01 00:00:00

abstract：:We propose a Bayesian latent Ornstein-Uhlenbeck (OU) model to analyze unbalanced longitudinal data of binary and ordinal variables, which are manifestations of fewer continuous latent variables. We focus on the evolution of such latent variables when they continuously change over time. Existing approaches are limited ...

journal_title：Biometrics

authors： Tran TD,Lesaffre E,Verbeke G,Duyck J

更新日期：2020-05-11 00:00:00

abstract：:Recent developments in the animal breeding literature facilitate estimation of the variance components in quantitative genetic models. However, computation remains intensive, and many of the procedures are restricted to specialized designs and models, unsuited to data arising from studies of natural populations. We de...

journal_title：Biometrics

authors： Thompson EA,Shaw RG

更新日期：1990-06-01 00:00:00

abstract：:Spatial replication is a common theme in count surveys of animals. Such surveys often generate sparse count data from which it is difficult to estimate population size while formally accounting for detection probability. In this article, I describe a class of models (N-mixture models) which allow for estimation of pop...

journal_title：Biometrics

authors： Royle JA

更新日期：2004-03-01 00:00:00

abstract：:Treatments are frequently evaluated in terms of their effect on patient survival. In settings where randomization of treatment is not feasible, observational data are employed, necessitating correction for covariate imbalances. Treatments are usually compared using a hazard ratio. Most existing methods which quantify ...

journal_title：Biometrics

authors： Gong Q,Schaubel DE

更新日期：2017-03-01 00:00:00

abstract：:This article develops a latent model and likelihood-based inference to detect temporal clustering of events. The model mimics typical processes generating the observed data. We apply model selection techniques to determine the number of clusters, and develop likelihood inference and a Monte Carlo expectation-maximizat...

journal_title：Biometrics

authors： Xie M,Sun Q,Naus J

更新日期：2009-12-01 00:00:00

abstract：:Capture-recapture models are widely used to estimate demographic parameters of marked populations. Recently, this statistical theory has been extended to modeling dispersal of open populations. Multistate models can be used to estimate movement probabilities among subdivided populations if multiple sites are sampled. ...

journal_title：Biometrics

authors： Lindberg MS,Kendall WL,Hines JE,Anderson MG

更新日期：2001-03-01 00:00:00

abstract：:Parametric survival functions are usually defined as explicit functions of time and covariates. However, consideration of some simple differential equations describing certain survival curves leads to a descriptive equation which cannot be explicitly solved for the survival function. Nevertheless, the resulting surviv...

journal_title：Biometrics

authors： Piantadosi S,Crowley J

更新日期：1995-03-01 00:00:00

abstract：:Alterations in DNA methylation have been linked to the development and progression of many diseases. The bisulfite sequencing technique presents methylation profiles at base resolution. Count data on methylated and unmethylated reads provide information on the methylation level at each CpG site. As more bisulfite sequ...

journal_title：Biometrics

authors： Ji T

更新日期：2019-06-01 00:00:00

abstract：:We consider a semiparametric regression model that relates a normal outcome to covariates and a genetic pathway, where the covariate effects are modeled parametrically and the pathway effect of multiple gene expressions is modeled parametrically or nonparametrically using least-squares kernel machines (LSKMs). This un...

journal_title：Biometrics

authors： Liu D,Lin X,Ghosh D

更新日期：2007-12-01 00:00:00

abstract：:Phase I trials to study the pharmacokinetic properties of a new drug generally involve a restricted number of healthy volunteers. Because of the nature of the group involved in such studies, the appropriate distributional assumptions are not always obvious. These model assumptions include the actual distribution but a...

journal_title：Biometrics

authors： Lindsey JK,Byrom WD,Wang J,Jarvis P,Jones B

更新日期：2000-03-01 00:00:00

abstract：:ChIP-chip (or ChIP-on-chip) is a technology for isolation and identification of genomic sites occupied by specific DNA-binding proteins in living cells. The ChIP-chip signals can be obtained over the whole genome by tiling arrays, where a peak shape is generally observed around a protein-binding site. In this article,...

journal_title：Biometrics

authors： Zheng M,Barrera LO,Ren B,Wu YN

更新日期：2007-09-01 00:00:00

abstract：:Multipoint linkage analysis is being performed routinely in medical genetic studies to localize disease genes. This likelihood-based method is very computationally intensive. Exact computations are thus formidable for problems with large number of genetic markers and complex pedigrees. This paper proposes a Monte Carl...

journal_title：Biometrics

authors： Lin S

更新日期：1996-12-01 00:00:00

abstract：:Brain connectivity analysis is now at the foreground of neuroscience research. A connectivity network is characterized by a graph, where nodes represent neural elements such as neurons and brain regions, and links represent statistical dependence that is often encoded in terms of partial correlation. Such a graph is i...

journal_title：Biometrics

authors： Xia Y,Li L

更新日期：2017-09-01 00:00:00

abstract：:In this article, we propose approximate sample size formulas for establishing equivalence or noninferiority of two treatments in match-pairs design. Using the ratio of two proportions as the equivalence measure, we derive sample size formulas based on a score statistic for two types of analyses: hypothesis testing and...

journal_title：Biometrics

authors： Tang ML,Tang NS,Chan IS,Chan BP

更新日期：2002-12-01 00:00:00

abstract：:This article describes the theoretical and practical issues in experimental design for gene expression microarrays. Specifically, this article 1) discusses the basic principles of design (randomization, replication, and blocking) as they pertain to microarrays, and 2) provides some general guidelines for statisticians...

journal_title：Biometrics

authors： Kerr MK

更新日期：2003-12-01 00:00:00

abstract：:Combined maximum likelihood estimates for equicorrelation covariance matrices are considered. The case of a common equicorrelation rho and possibly different standard deviations sigma 1, ..., sigma k among k experimental groups is examined first, and the estimation of (rho, sigma 1, ..., sigma k) is discussed. Second,...

journal_title：Biometrics

authors： Viana MA

更新日期：1994-09-01 00:00:00

abstract：:Despite major methodological developments, Bayesian inference in Gaussian graphical models remains challenging in high dimension due to the tremendous size of the model space. This article proposes a method to infer the marginal and conditional independence structures between variables by multiple testing, which bypas...

journal_title：Biometrics

authors： Leday GGR,Richardson S

更新日期：2019-12-01 00:00:00

abstract：:The use of three periods in the two-treatment crossover design for clinical trials is considered. It is proposed that a series of such trials in a particular therapeutic area may establish the relevance of the crossover design in that area. Treatment sequences to be used in three-period two-treatment trials are discus...

journal_title：Biometrics

authors： Ebbutt AF

更新日期：1984-03-01 00:00:00

abstract：:The simultaneous testing of multiple hypotheses is common to the analysis of high-dimensional data sets. The two-group model, first proposed by Efron, identifies significant comparisons by allocating observations to a mixture of an empirical null and an alternative distribution. In the Bayesian nonparametrics literatu...

journal_title：Biometrics

authors： Denti F,Guindani M,Leisen F,Lijoi A,Wadsworth WD,Vannucci M

更新日期：2020-06-14 00:00:00

abstract：:Functional mapping is a useful tool for mapping quantitative trait loci (QTL) that control dynamic traits. It incorporates mathematical aspects of biological processes into the mixture model-based likelihood setting for QTL mapping, thus increasing the power of QTL detection and the precision of parameter estimation. ...

journal_title：Biometrics

authors： Yang J,Wu R,Casella G

更新日期：2009-03-01 00:00:00

abstract：:Often with data from immunoassays, the concentration-response relationship is nonlinear and intra-assay response variance is heterogeneous. Estimation of the standard curve is usually based on a nonlinear heteroscedastic regression model for concentration-response, where variance is modeled as a function of mean respo...

journal_title：Biometrics

authors： Belanger BA,Davidian M,Giltinan DM

更新日期：1996-03-01 00:00:00

abstract：:Eguchi and Matsuura (1990, Biometrics 46, 415-426) noted that the generalized Stevens test statistic for the Hardy-Weinberg law for human leukocyte antigen (HLA) data yields an excessively large value when no double blanks are observed. In this paper, we investigated this aberrant case. The inflated value of the test ...

journal_title：Biometrics

authors： Nam J

更新日期：1995-03-01 00:00:00