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作者：Baiocchi, Mike; Small, Dylan S.; Lorch, Scott; Rosenbaum, Paul R.
作者单位：University of Pennsylvania; University of Pennsylvania; University of Pennsylvania; Pennsylvania Medicine; Childrens Hospital of Philadelphia
摘要：An instrument is a random nudge toward acceptance of a treatment that affects outcomes only to the extent that it affects acceptance of the treatment. Nonetheless, in settings in which treatment assignment is mostly deliberate and not random, there may exist some essentially random nudges to accept treatment, so that use of an instrument might extract bits of random treatment assignment from a setting that is otherwise quite biased in its treatment assignments. An instrument is weak if the ran...
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作者：Wang, C.; Daniels, M. J.; Scharfstein, D. O.; Land, S.
作者单位：State University System of Florida; University of Florida; US Food & Drug Administration (FDA); Johns Hopkins University; Johns Hopkins Bloomberg School of Public Health; Pennsylvania Commonwealth System of Higher Education (PCSHE); University of Pittsburgh
摘要：We consider inference in randomized longitudinal studies with missing data that is generated by skipped clinic visits and loss to followup. In this setting, it is well known that full data estimands are not identified unless unverified assumptions are imposed. We assume a non-future dependence model for the drop-out mechanism and partial ignorability for the intermittent missingness. We posit an exponential tilt model that links nonidentifiable distributions and distributions identified under ...
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作者：Abadie, Alberto; Diamond, Alexis; Hainmueller, Jens
作者单位：Harvard University; Massachusetts Institute of Technology (MIT)
摘要：Building on an idea in Abadie and Gardeazabal (2003), this article investigates the application of synthetic control methods to comparative case studies. We discuss the advantages of these methods and apply them to study the effects of Proposition 99, a large-scale tobacco control program that California implemented in 1988. We demonstrate that. following Proposition 99, tobacco consumption fell markedly in California relative to a comparable synthetic control region. We estimate that by the y...
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作者：Peress, Michael; Spirling, Arthur
作者单位：University of Rochester; Harvard University; Harvard University
摘要：We study the critical opinions of expert movie reviewers as an item response problem Building on earlier unfolding models, we develop a framework that models an individual's decision to approve of disapprove of an item Using this approach we are able to recover the locations of movies and ideal points of critics in the same multidimensional space We demonstrate that a three-dimensional model captures much of the variation in critical opinions The first dimension signifies movie quality while t...
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作者：Cressie, Noel; Tingley, Martin P.
作者单位：University System of Ohio; Ohio State University; University System of Ohio; Ohio State University
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作者：Cressie, Noel; O'Donnell, David
作者单位：University System of Ohio; Ohio State University; University of Glasgow
摘要：This note is based on an invited discussion of the article, A Moving Average Approach for Spatial Statistical Models on Stream Networks by Jay M Ver Hoef and Erin E Peterson Ver Hod and Peterson (hereafter VHP) have extended the idea of flow-related statistical dependence in streams to one where dependence may not respect flow. such as might happen when modeling data on fish in connected streams We congratulate VHP for their innovative paper on using moving average models in stream networks
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作者：Morton, Sally C.
作者单位：Research Triangle Institute
摘要：The discipline of statistics, we as individual statisticians, and the American Statistical Association (ASA) have been called to action We can and must play a vital part in the gathering. analysis. interpretation. and communication of evidence for informed policy decisions I ask you to answer yes and to take on the role of an honest broker of policy alternatives I ask you to support a proactive engagement by the ASA in informing policy While interaction in policy forums by the ASA is an opport...
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作者：Cai, T. Tony
作者单位：University of Pennsylvania
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作者：Rosenbaum, Paul R.
作者单位：University of Pennsylvania
摘要：An observational study attempts to draw inferences about the effects caused by a treatment when subjects are not randomly assigned to treatment or control as they would be in a randomized trial. After adjustments have been made for imbalances in measured covariates, the key source of uncertainty in an observational study is the possibility that subjects were not comparable prior to treatment in terms of some unmeasured covariate, so that differing outcomes in treated and control groups are not...
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作者：Chen, Rong; Guo, Re-Jin; Lin, Ming
作者单位：Rutgers University System; Rutgers University New Brunswick; Peking University; University of Illinois System; University of Illinois Chicago; University of Illinois Chicago Hospital; Xiamen University
摘要：Examination on firm performance subsequent to a chosen event is widely used in finance studies to analyze the motivation behind managerial decisions. However, results are often subject to bias when the self-selectivity behind managerial decisions is ignored and unspecified. This study investigates a unique corporate event of initial public offering (IPO) withdrawal, where a firm's subsequent likelihood of bankruptcy is specified in a system of switching hazard models, and the expected differen...
