2001

最新文章

• Evaluation of traffic injury prevention programs using counting process approaches AI翻译
  作者：Sun, JG; Kim, YJ; Hewett, J; Johnson, JC; Farmer, J; Gibler, M
  作者单位：University of Missouri System; University of Missouri Columbia; University of Missouri System; University of Missouri Columbia
  摘要：Traumatic brain injury (TBI) is among the most devastating of injuries leading to death and disability among young people today. The major cause of TBI is motor vehicle crashes. One way to reduce the rates of such crashes and thus TBI is through prevention programs. This article analyzes a study conducted for assessing a 1-day educational traffic injury prevention program for young traffic offenders with speeding violations. The obtained data include information about traffic convictions for s...
• Likelihood-based methods for missing covariates in the Cox proportional hazards model AI翻译
  作者：Herring, AH; Ibrahim, JG
  作者单位：University of North Carolina; University of North Carolina Chapel Hill; Harvard University; Harvard T.H. Chan School of Public Health; Harvard University; Harvard University Medical Affiliates; Dana-Farber Cancer Institute
  摘要：Problems associated with missing covariate data are well known but often ignored. We present a method for estimating the parameters in the Cox proportional hazards model when the missing data are missing at random (MAR) and censoring is noninformative. Due to the computational burden of this method, we introduce an approximation that allows us to use a weighted expectation-maximization (EM) algorithm to estimate the parameters more easily. When the missing covariates are continuous rather than...
• Semiparametric and nonparametric regression analysis of longitudinal data - Comment AI翻译
  作者：Hoover, DR; Wu, CO
  作者单位：Rutgers University System; Rutgers University New Brunswick; Johns Hopkins University
• Cluster identification using projections AI翻译
  作者：Peña, D; Prieto, FJ
  作者单位：Universidad Carlos III de Madrid
  摘要：This article describes a procedure to identify clusters in multivariate data using information obtained from the univariate projections of the sample data onto certain directions. The directions are chosen as those that minimize and maximize the kurtosis coefficient of the projected data. It is shown that, under certain conditions, these directions provide the largest separation for the different clusters. The projected univariate data are used to group the observations according to the values...
• Local likelihood analysis of survival data with censored intermediate events AI翻译
  作者：Bebchuk, JD; Betensky, RA
  作者单位：University of Minnesota System; University of Minnesota Twin Cities; Harvard University; Harvard T.H. Chan School of Public Health
  摘要：AIDS Clinical Trials Group protocol 193A was a randomized trial designed to compare survival and progression-free survival among patients on different treatment regimens. A complicating feature of the analysis of progression-free survival is that different censoring mechanisms operated on progression and survival, which resulted in more complete information on survival. A simple analysis that uses the minimum of the times to progression and survival and the minimum of the corresponding censori...
• Density estimation under random censorship and order restrictions: From asymptotic to small samples AI翻译
  作者：Efromovich, S
  作者单位：University of New Mexico
  摘要：Do a random censorship and/or order restrictions (e.g., nonnegativity, monotonicity, convexity) affect estimation of a smooth density under mean integrated squared error (MISE)? Under mild assumptions, the known asymptotic results, which are concerned only with rates, answer no. This answer, especially for censored data, contradicts practical experience and statistical intuition. So what can be said about constants of MISE convergence? It is shown that asymptotically (a) censorship does affect...
• Effect of insurance on mortality in an HIV-positive population in care AI翻译
  作者：Goldman, DR; Bhattacharya, J; McCaffrey, DF; Duan, N; Leibowitz, AA; Joyce, GF; Morton, SC
  作者单位：RAND Corporation; University of California System; University of California Los Angeles; University of California Los Angeles Medical Center; David Geffen School of Medicine at UCLA; University of California System; University of California Los Angeles
  摘要：As policymakers consider expanding insurance coverage for individuals infected with human immunodeficiency virus (HIV), it is useful to ask if insurance has any affect on health outcomes and, if so, whether its magnitude has changed with recent efficacious but expensive treatments. By using data from a nationally representative cohort of HIV-infected (HIV+) persons receiving regular medical care, we estimate the impact of insurance on mortality in this population. A naive single-equation model...
• Inference for the complier-average causal effect from longitudinal data subject to noncompliance and missing data, with application to a job training assessment for the unemployed AI翻译
  作者：Yau, LHY; Little, RJ
  作者单位：GlaxoSmithKline; Glaxosmithkline USA; University of Michigan System; University of Michigan
  摘要：Longitudinal studies involving human participants are often complicated by subjects who do not comply with their treatment assignment or do not provide complete data. A treatment effect of interest in the presence of noncompliance is the complier-average causal effect (CACE; Imbens and Rubin 1997a), which is the treatment effect for subjects who would comply regardless of the assigned treatment. Imbens and Rubin (1997a,b) proposed maximum likelihood and Bayesian inferential methods for CACE, w...
• Spatiotemporal hierarchical Bayesian modeling: Tropical ocean surface winds AI翻译
  作者：Wikle, CK; Milliff, RF; Nychka, D; Berliner, LM
  作者单位：University of Missouri System; University of Missouri Columbia; National Center Atmospheric Research (NCAR) - USA; University System of Ohio; Ohio State University
  摘要：Spatiotemporal processes are ubiquitous in the environmental and physical sciences. This is certainly true of atmospheric and oceanic processes, which typically exhibit many different scales of spatial and temporal variability. The complexity of these processes and the large number of observation/prediction locations preclude the use of traditional covariance-based spatiotemporal statistical methods. Alternatively, we focus on conditionally specified (i.e., hierarchical) spatiotemporal models....
• Jackknife variance estimation for nearest-neighbor imputation AI翻译
  作者：Chen, JH; Shao, J
  作者单位：University of Waterloo; University of Wisconsin System; University of Wisconsin Madison
  摘要：Nearest-neighbor imputation is a popular hot deck imputation method used to compensate for nonresponse in sample surveys. Although this method has a long history of application, the problem of variance estimation after nearest-neighbor imputation has not been fully investigated. Because nearest-neighbor imputation is a nonparametric method, a nonparametric variance estimation technique, such as the jackknife, is desired. We show that the naive jackknife that treats imputed values as observed d...