4期

最新文章

• Strong control of the familywise error rate in observational studies that discover effect modification by exploratory methods AI翻译
  作者：Hsu, Jesse Y.; Zubizarreta, Jose R.; Small, Dylan S.; Rosenbaum, Paul R.
  作者单位：University of Pennsylvania; Columbia University; University of Pennsylvania
  摘要：An effect modifier is a pretreatment covariate that affects the magnitude of the treatment effect or its stability. When there is effect modification, an overall test that ignores an effect modifier may be more sensitive to unmeasured bias than a test that combines results from subgroups defined by the effect modifier. If there is effect modification, one would like to identify specific subgroups for which there is evidence of effect that is insensitive to small or moderate biases. In this pap...
• Clarifying missing at random and related definitions, and implications when coupled with exchangeability AI翻译
  作者：Mealli, Fabrizia; Rubin, Donald B.
  作者单位：University of Florence; Harvard University
  摘要：We clarify the key concept of missingness at random in incomplete data analysis. We first distinguish between data being missing at random and the missingness mechanism being a missing-at-random one, which we call missing always at random and which is more restrictive. We further discuss how, in general, neither of these conditions is a statement about conditional independence. We then consider the implication of the more restrictive missing-always-at-random assumption when coupled with full u...
• Nonparametric methods for group testing data, taking dilution into account AI翻译
  作者：Delaigle, A.; Hall, P.
  作者单位：University of Melbourne
  摘要：Group testing methods are used widely to assess the presence of a contaminant, based on measurements of the concentration of a biomarker, for example to test the presence of a disease in pooled blood samples. The test would be perfect if it produced a positive result whenever the contaminant was present, and a negative result otherwise. However, in practice the test is always at least somewhat imperfect, for example because it is sensitive to the proportion of contaminated items in the group, ...
• Score tests for association under response-dependent sampling designs for expensive covariates AI翻译
  作者：Derkach, Andriy; Lawless, Jerald F.; Sun, Lei
  作者单位：University of Toronto; University of Waterloo; University of Toronto
  摘要：Response-dependent sampling is widely used in settings where certain variables are expensive to obtain. Estimation has been thoroughly investigated but recent applications have emphasized tests of association for expensive covariates and a response variable. We consider testing and provide easily implemented likelihood score tests for generalized linear models under a broad range of sampling plans. We show that when there are no additional covariates, the score statistics are identical for con...
• Bayesian inference for partially observed stochastic differential equations driven by fractional Brownian motion AI翻译
  作者：Beskos, A.; Dureau, J.; Kalogeropoulos, K.
  作者单位：University of London; University College London; University of London; London School Economics & Political Science
  摘要：We consider continuous-time diffusion models driven by fractional Brownian motion. Observations are assumed to possess a nontrivial likelihood given the latent path. Due to the non-Markovian and high-dimensional nature of the latent path, estimating posterior expectations is computationally challenging. We present a reparameterization framework based on the Davies and Harte method for sampling stationary Gaussian processes and use it to construct a Markov chain Monte Carlo algorithm that allow...
• Locally optimal designs for errors-in-variables models AI翻译
  作者：Konstantinou, M.; Dette, H.
  作者单位：Ruhr University Bochum
  摘要：We consider the construction of optimal designs for nonlinear regression models when there are measurement errors in the covariates. Corresponding approximate design theory is developed for maximum likelihood and least-squares estimation, with the latter leading to nonconcave optimization problems. Analytical characterizations of the locally D-optimal saturated designs are provided for the Michaelis-Menten, E-max and exponential regression models. Through concrete applications, we illustrate h...
• Changepoint estimation: another look at multiple testing problems AI翻译
  作者：Cao, Hongyuan; Wu, Wei Biao
  作者单位：University of Missouri System; University of Missouri Columbia; University of Chicago
  摘要：We consider large scale multiple testing for data that have locally clustered signals. With this structure, we apply techniques from changepoint analysis and propose a boundary detection algorithm so that the clustering information can be utilized. Consequently the precision of the multiple testing procedure is substantially improved. We study tests with independent as well as dependent p-values. Monte Carlo simulations suggest that the methods perform well with realistic sample sizes and show...
• General weighted optimality of designed experiments AI翻译
  作者：Stallings, J. W.; Morgan, J. P.
  作者单位：North Carolina State University; Virginia Polytechnic Institute & State University
  摘要：The standard approach to finding optimal experimental designs employs conventional measures of design efficacy, such as the A, E, and D-criterion, that assume equal interest in all estimable functions of model parameters. This paper develops a general theory for weighted optimality, allowing precise design selection according to expressed relative interest in different functions in the estimation space. The approach employs a very general class of matrix-specified weighting schemes that produc...
• Consistent testing for recurrent genomic aberrations AI翻译
  作者：Walter, V.; Wright, F. A.; Nobel, A. B.
  作者单位：Pennsylvania Commonwealth System of Higher Education (PCSHE); Pennsylvania State University; Penn State Health; North Carolina State University; University of North Carolina; University of North Carolina Chapel Hill
  摘要：We consider the detection and identification of recurrent departures from stationary behaviour in genomic or similarly arranged data containing measurements at an ordered set of variables. Our primary focus is on departures that occur only at a single variable, or within a small window of contiguous variables, but involve more than one sample. This encompasses the identification of aberrant markers in genome-wide measurements of DNA copy number and DNA methylation, as well as meta-analyses of ...
• Direct estimation of the mean outcome on treatment when treatment assignment and discontinuation compete AI翻译
  作者：Lu, Xin; Johnson, Brent A.
  作者单位：Emory University; Rollins School Public Health; University of Rochester
  摘要：Several authors have investigated the challenges of statistical analyses and inference in the presence of early treatment termination, including a loss of efficiency in randomized controlled trials and a connection to dynamic regimes in observational studies. Popular estimation strategies for causal estimands in dynamic regimes lend themselves to studies where treatment is assigned at a finite number of points and the extension to continuous treatment assignment is nontrivial. We re-examine th...