A study of deleterious gene structure in plants using Markov chain Monte Carlo.

abstract：:For the same number of observations in a small-sample clinical trial with dichotomous outcome, the statistical power associated with a two-sample design, analyzed by Fisher's exact test, is slightly greater than that associated with a matched design, analyzed by McNemar's test, and hence of the matched design, is mono...

journal_title：Biometrics

authors： Wacholder S,Weinberg CR

更新日期：1982-09-01 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：:An important objective in biomedical and environmental risk assessment is estimation of minimum exposure levels that induce a pre-specified adverse response in a target population. The exposure points in such settings are typically referred to as benchmark doses (BMDs). Parametric Bayesian estimation for finding BMDs ...

journal_title：Biometrics

authors： Fang Q,Piegorsch WW,Simmons SJ,Li X,Chen C,Wang Y

更新日期：2015-12-01 00:00:00

abstract：:We consider Bayesian methodology for comparing two or more unlabeled point sets. Application of the technique to a set of steroid molecules illustrates its potential utility involving the comparison of molecules in chemoinformatics and bioinformatics. We initially match a pair of molecules, where one molecule is regar...

journal_title：Biometrics

authors： Dryden IL,Hirst JD,Melville JL

更新日期：2007-03-01 00:00:00

abstract：:The approach to early termination for efficacy in a trial where events occur over time but the primary question of interest relates to a long-term binary endpoint is not straightforward. This article considers comparison of treatment groups with Kaplan-Meier (KM) proportions evaluated at increasing times from randomiz...

journal_title：Biometrics

authors： Brittain E,Follmann D,Yang S

更新日期：2008-03-01 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：:Life-table methodology for interval-censored survival times is used to estimate marginal survival probabilities from data consisting of independent cohorts of correlated responses. We restrict our attention to situations where response times within cohorts are exchangeable and the marginal survival distributions are t...

journal_title：Biometrics

authors： Kang SS,Koehler KJ

更新日期：1997-09-01 00:00:00

abstract：:We present an approach for analyzing internal dependencies in counting processes. This covers the case with repeated events on each of a number of individuals, and more generally, the situation where several processes are observed for each individual. We define dynamic covariates, i.e., covariates depending on the pas...

journal_title：Biometrics

authors： Aalen OO,Fosen J,Weedon-Fekjaer H,Borgan O,Husebye E

更新日期：2004-09-01 00:00:00

abstract：:In family studies, canonical discriminant analysis can be used to find linear combinations of phenotypes that exhibit high ratios of between-family to within-family variabilities. But with large numbers of phenotypes, canonical discriminant analysis may overfit. To estimate the predicted ratios associated with the coe...

journal_title：Biometrics

authors： Jin M,Fang Y

更新日期：2011-03-01 00:00:00

abstract：:Johnson and Wehrly (1978, Journal of the American Statistical Association 73, 602-606) and Wehrly and Johnson (1980, Biometrika 67, 255-256) show one way to construct the joint distribution of a circular and a linear random variable, or the joint distribution of a pair of circular random variables from their marginal ...

journal_title：Biometrics

authors： Fernández-Durán JJ

更新日期：2007-06-01 00:00:00

abstract：:The variogram is a standard tool in the analysis of spatial data, and its shape provides useful information on the form of spatial correlation that may be present. However, it is also useful to be able to assess the evidence for the presence of any spatial correlation. A method of doing this, based on an assessment of...

journal_title：Biometrics

authors： Diblasi A,Bowman AW

更新日期：2001-03-01 00:00:00

abstract：:Procedures for estimating the genetic parameters of plant populations frequently employ progeny testing to ascertain the genotype of maternal plants. However, when experimental resources are limited (e.g., electrophoretic markers), the large progeny sizes required for accurate typing severely restricts the numbers of ...

journal_title：Biometrics

authors： Brown AH

更新日期：1975-03-01 00:00:00

abstract：:Directed acyclic graphical (DAG) models are increasingly employed in the study of physical and biological systems to model direct influences between variables. Identifying the graph from data is a challenging endeavor, which can be more reasonably tackled if the variables are assumed to satisfy a given ordering; in th...

journal_title：Biometrics

authors： Altomare D,Consonni G,La Rocca L

更新日期：2013-06-01 00:00:00

abstract：:Methods for modeling and mapping spatial variation in disease risk continue to motivate much research. In particular, spatial analyses provide a useful tool for exploring geographical heterogeneity in health outcomes, and consequently can yield clues as to disease etiology, direct public health management, and generat...

journal_title：Biometrics

authors： Costain DA

更新日期：2009-12-01 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：:The problem of regression dilution arising from covariate measurement error is investigated for survival data using the proportional hazards model. The naive approach to parameter estimation is considered whereby observed covariate values are used, inappropriately, in the usual analysis instead of the underlying covar...

journal_title：Biometrics

authors： Hughes MD

更新日期：1993-12-01 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：:We propose a new estimation method for multivariate failure time data using the quadratic inference function (QIF) approach. The proposed method efficiently incorporates within-cluster correlations. Therefore, it is more efficient than those that ignore within-cluster correlation. Furthermore, the proposed method is e...

journal_title：Biometrics

authors： Xue L,Wang L,Qu A

更新日期：2010-06-01 00:00:00

abstract：:When a true survival endpoint cannot be assessed for some subjects, an alternative endpoint that measures the true endpoint with error may be collected, which often occurs when obtaining the true endpoint is too invasive or costly. We develop an estimated likelihood function for the situation where we have both uncert...

journal_title：Biometrics

authors： Zee J,Xie SX

更新日期：2015-09-01 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：:A nonparametric maximum likelihood procedure is given for estimating the survivor function from right-censored data. It approximates the hazard rate by a simple function such as a spline, with different approximations yielding different estimators. A special case is that proposed by Nelson (1969, Journal of Quality Te...

journal_title：Biometrics

authors： Whittemore AS,Keller JB

更新日期：1986-09-01 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：:The matrix considered contains four elements, each a function of total number. A special case for which the matrix may be appropriate is when the population may be divided into juveniles and adults, and the survival rates and fecundity are the same for all members of each group. This is true, at least approximatley, f...

journal_title：Biometrics

authors： Cooke D,Leon JA

更新日期：1976-06-01 00:00:00

abstract：:Thanks to the growing interest in personalized medicine, joint modeling of longitudinal marker and time-to-event data has recently started to be used to derive dynamic individual risk predictions. Individual predictions are called dynamic because they are updated when information on the subject's health profile grows ...

journal_title：Biometrics

authors： Blanche P,Proust-Lima C,Loubère L,Berr C,Dartigues JF,Jacqmin-Gadda H

更新日期：2015-03-01 00:00:00

abstract：:A topic of current biometric discussion is whether stratification should be used in randomized clinical trials and, if so, which kind. An approach based upon randomization theory is used to evaluate pre- versus post-stratification. The results obtained relate specifically to the effect of the size of the clinical tria...

journal_title：Biometrics

authors： McHugh R,Matts J

更新日期：1983-03-01 00:00:00

abstract：:Detecting changes in longitudinal data is important in medical research. However, the existence of measurement outliers can cause an unexpected increase in the false alarm rate in claiming changes. To reduce the outliers, a new method has been developed. In this scheme, two measures are initially taken and, if they ar...

journal_title：Biometrics

authors： Namgung YY,Yang MC

更新日期：1994-03-01 00:00:00

abstract：:We consider inference for the reaction rates in discretely observed networks such as those found in models for systems biology, population ecology, and epidemics. Most such networks are neither slow enough nor small enough for inference via the true state-dependent Markov jump process to be feasible. Typically, infere...

journal_title：Biometrics

authors： Fearnhead P,Giagos V,Sherlock C

更新日期：2014-06-01 00:00:00

abstract：:In clinical trials and other investigations of survival time, information is often available on a time-dependent event other than survival. An example of such an auxiliary event in cancer studies is objective progression of disease. While some patients expire without experiencing objective disease progression, others ...

journal_title：Biometrics

authors： Lagakos SW

更新日期：1976-09-01 00:00:00

abstract：:If the regulatory requirements are symmetrical, the use of symmetrical confidence intervals as a decision rule for bioequivalence assessment leads, as shown by simulations, to better level properties and an inferior power compared to a rule based on shortest confidence intervals. A choice between these two approaches ...

journal_title：Biometrics

authors： Mandallaz D,Mau J

更新日期：1981-06-01 00:00:00

abstract：:Highly active antiretroviral therapy (HAART) has proved efficient in increasing CD4 counts in many randomized clinical trials. Because randomized trials have some limitations (e.g., short duration, highly selected subjects), it is interesting to assess the effect of treatments using observational studies. This is chal...

journal_title：Biometrics

authors： Prague M,Commenges D,Gran JM,Ledergerber B,Young J,Furrer H,Thiébaut R

更新日期：2017-03-01 00:00:00