Design considerations for efficient and effective microarray studies.

abstract：:Training data in a supervised learning problem consist of the class label and its potential predictors for a set of observations. Constructing effective classifiers from training data is the goal of supervised learning. In biomedical sciences and other scientific applications, class labels may be subject to errors. We...

journal_title：Biometrics

authors： Yasui Y,Pepe M,Hsu L,Adam BL,Feng Z

更新日期：2004-03-01 00:00:00

abstract：:When the observed data are contaminated with errors, the standard two-sample testing approaches that ignore measurement errors may produce misleading results, including a higher type-I error rate than the nominal level. To tackle this inconsistency, a nonparametric test is proposed for testing equality of two distribu...

journal_title：Biometrics

authors： Lee D,Lahiri SN,Sinha S

更新日期：2020-09-01 00:00:00

abstract：:In binomial group testing, unlike one-at-a-time testing, the test unit consists of a group of individuals, and each group is declared to be defective or nondefective. A defective group is one that is presumed to include one or more defective (e.g., infected, positive) individuals and a nondefective group to contain on...

journal_title：Biometrics

authors： Hung M,Swallow WH

更新日期：1999-03-01 00:00:00

abstract：SUMMARY:Nonparametric regression models are proposed in the framework of ecological inference for exploratory modeling of disease prevalence rates adjusted for variables, such as age, ethnicity/race, and socio-economic status. Ecological inference is needed when a response variable and covariate are not available at th...

journal_title：Biometrics

authors： Staniswalis JG

更新日期：2008-12-01 00:00:00

abstract：:Given a large number of t-statistics, we consider the problem of approximating the distribution of noncentrality parameters (NCPs) by a continuous density. This problem is closely related to the control of false discovery rates (FDR) in massive hypothesis testing applications, e.g., microarray gene expression analysis...

journal_title：Biometrics

authors： Qu L,Nettleton D,Dekkers JC

更新日期：2012-12-01 00:00:00

abstract：:The validation of surrogate endpoints has been studied by Prentice (1989, Statistics in Medicine 8, 431-440) and Freedman, Graubard, and Schatzkin (1992, Statistics in Medicine 11, 167-178). We extended their proposals in the cases where the surrogate and the final endpoints are both binary or normally distributed. Le...

journal_title：Biometrics

authors： Buyse M,Molenberghs G

更新日期：1998-09-01 00:00:00

abstract：:Variable selection for clustering is an important and challenging problem in high-dimensional data analysis. Existing variable selection methods for model-based clustering select informative variables in a "one-in-all-out" manner; that is, a variable is selected if at least one pair of clusters is separable by this va...

journal_title：Biometrics

authors： Guo J,Levina E,Michailidis G,Zhu J

更新日期：2010-09-01 00:00:00

abstract：:Moment methods for analyzing repeated binary responses have been proposed by Liang and Zeger (1986, Biometrika 73, 13-22), and extended by Prentice (1988, Biometrics 44, 1033-1048). In their generalized estimating equations (GEE), both Liang and Zeger (1986) and Prentice (1988) estimate the parameters associated with ...

journal_title：Biometrics

authors： Lipsitz SR,Fitzmaurice GM,Orav EJ,Laird NM

更新日期：1994-03-01 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：SUMMARY:Many hormones are secreted in pulses. The pulsatile relationship between hormones regulates many biological processes. To understand endocrine system regulation, time series of hormone concentrations are collected. The goal is to characterize pulsatile patterns and associations between hormones. Currently each ...

journal_title：Biometrics

authors： Carlson NE,Johnson TD,Brown MB

更新日期：2009-06-01 00:00:00

abstract：:In a study designed to assess the relationship between a dichotomous exposure and the eventual occurrence of a dichotomous outcome, frequency matching has been proposed as a way to balance the exposure cohorts with respect to the sampling distribution of potential confounding factors. This paper discusses the pooled e...

journal_title：Biometrics

authors： Weinberg CR

更新日期：1985-03-01 00:00:00

abstract：:In this article, we present an estimation approach for solving nonlinear constrained generalized estimating equations that can be implemented using object-oriented software for nonlinear programming, such as nlminb in Splus or fmincon and lsqnonlin in Matlab. We show how standard estimating equation theory includes th...

journal_title：Biometrics

authors： Contreras M,Ryan LM

更新日期：2000-12-01 00:00:00

abstract：:In diagnostic medicine, estimating the diagnostic accuracy of a group of raters or medical tests relative to the gold standard is often the primary goal. When a gold standard is absent, latent class models where the unknown gold standard test is treated as a latent variable are often used. However, these models have b...

journal_title：Biometrics

authors： Zhang B,Chen Z,Albert PS

更新日期：2012-12-01 00:00:00

abstract：:In multivariate recurrent event data regression, observation of recurrent events is usually terminated by other events that are associated with the recurrent event processes, resulting in informative censoring. Additionally, some covariates could be measured with errors. In some applications, an instrumental variable ...

journal_title：Biometrics

authors： Yu H,Cheng YJ,Wang CY

更新日期：2018-09-01 00:00:00

abstract：:Long-term follow-up is common in many medical investigations where the interest lies in predicting patients' risks for a future adverse outcome using repeatedly measured predictors over time. A key quantity is the likelihood of developing an adverse outcome among individuals who survived up to time s given their covar...

journal_title：Biometrics

authors： Maziarz M,Heagerty P,Cai T,Zheng Y

更新日期：2017-03-01 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：:Conventional statistical determinations of sample size in phase II studies typically lead to sample sizes of the order of 25 (Schoenfeld, 1980, International Journal of Radiation Oncology, Biology and Physics 6, 371-374). When the development of new treatments is proceeding rapidly relative to the recruitment of suita...

journal_title：Biometrics

authors： Whitehead J

更新日期：1985-06-01 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：:Motivated by the particular problem of predicting defoliation based on a measure of gypsy moth egg mass density, prediction in the presence of measurement error is discussed. The measurement error variances and covariances are allowed to vary from unit to unit and are estimated by some type of within unit sampling. A ...

journal_title：Biometrics

authors： Buonaccorsi JP

更新日期：1995-12-01 00:00:00

abstract：:Because the number of patients waiting for organ transplants exceeds the number of organs available, a better understanding of how transplantation affects the distribution of residual lifetime is needed to improve organ allocation. However, there has been little work to assess the survival benefit of transplantation f...

journal_title：Biometrics

authors： Vock DM,Tsiatis AA,Davidian M,Laber EB,Tsuang WM,Finlen Copeland CA,Palmer SM

更新日期：2013-12-01 00:00:00

abstract：:I discuss diagnostic methods for discriminant analysis. The equivalence with linear regression is noted and regression diagnostics are considered. The leverage is a function of the linear discriminant function and the Mahalanobis distance of the observation from the group mean. The distribution of this distance is app...

journal_title：Biometrics

authors： Lachenbruch PA

更新日期：1997-12-01 00:00:00

abstract：:With the prevalence of gene expression studies and the relatively low reproducibility caused by insufficient sample sizes, it is natural to consider joint analysis that could combine data from different experiments effectively to achieve improved accuracy. We present in this article a model-based approach for better i...

journal_title：Biometrics

authors： Ruan L,Yuan M

更新日期：2011-12-01 00:00:00

abstract：:The data set presented relates a binomial response to ordered levels of an explanatory variable, representing doses of a drug, with data collected at several centers. A study goal is to test independence of the response and the ordinal factor, assuming under the alternative only that the binomial parameter is a monoto...

journal_title：Biometrics

authors： Agresti A,Coull BA

更新日期：1996-09-01 00:00:00

abstract：:Large amounts of longitudinal health records are now available for dynamic monitoring of the underlying processes governing the observations. However, the health status progression across time is not typically observed directly: records are observed only when a subject interacts with the system, yielding irregular and...

journal_title：Biometrics

authors： Luo Y,Stephens DA,Verma A,Buckeridge DL

更新日期：2020-03-11 00:00:00

abstract：:It is not, in general, possible to include all relevant risk factors in a model of survival or disease incidence. This heterogeneity must be accounted for in the interpretation, as it can imply otherwise unexpected results. This is illustrated by diabetic nephropathy, a serious complication experienced by some diabeti...

journal_title：Biometrics

authors： Hougaard P,Myglegaard P,Borch-Johnsen K

更新日期：1994-12-01 00:00:00

abstract：:Multivariate failure time data arise when each study subject may experience several types of event or when there are clusterings of observational units such that failure times within the same cluster are correlated. The failure times are often subject to interval grouping or have truly discrete measurements. In this p...

journal_title：Biometrics

authors： Guo SW,Lin DY

更新日期：1994-09-01 00:00:00

abstract：SUMMARY:We develop sample size formulas for studies aiming to test mean differences between a treatment and control group when all-or-none nonadherence (noncompliance) and selection bias are expected. Recent work by Fay, Halloran, and Follmann (2007, Biometrics 63, 465-474) addressed the increased variances within grou...

journal_title：Biometrics

authors： Shardell MD,El-Kamary SS

更新日期：2009-06-01 00:00:00

abstract：:Heart rate oscillates in synchrony with respiration. Several methods have been employed to assess this 'sinus arrhythmia', as an index of autonomic nervous system function. This paper proposes a new, easily computed measure, R, which is relatively resistant to the major nonrespiratory sources of variation, including p...

journal_title：Biometrics

authors： Weinberg CR,Pfeifer MA

更新日期：1984-09-01 00:00:00

abstract：:R. A. Fisher is widely respected for his contributions to both statistics and genetics. For instance, his 1930 text on The Genetical Theory of Natural Selection remains a watershed contribution in that area. Fisher's subsequent research led him to study the work of (Johann) Gregor Mendel, the 19th century monk who fir...

journal_title：Biometrics

authors： Piegorsch WW

更新日期：1990-12-01 00:00:00

abstract：:Vaccine-induced protection may not be homogeneous across individuals. It is possible that a vaccine gives complete protection for a portion of individuals, while the rest acquire only incomplete (leaky) protection of varying magnitude. If vaccine efficacy is estimated under wrong assumptions about such individual leve...

journal_title：Biometrics

authors： Mehtälä J,Dagan R,Auranen K

更新日期：2016-09-01 00:00:00