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作者：Athey, Susan; Eckles, Dean; Imbens, Guido W.
作者单位：Stanford University; National Bureau of Economic Research; Massachusetts Institute of Technology (MIT)
摘要：We study the calculation of exact p-values for a large class of nonsharp null hypotheses about treatment effects in a setting with data from experiments involving members of a single connected network. The class includes null hypotheses that limit the effect of one unit's treatment status on another according to the distance between units, for example, the hypothesis might specify that the treatment status of immediate neighbors has no effect, or that units more than two edges away have no eff...
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作者：Bolton, Alexander D.; Heard, Nicholas A.
作者单位：Imperial College London; University of Bristol
摘要：Malware is computer software that has either been designed or modified with malicious intent. Hundreds of thousands of new malware threats appear on the internet each day. This is made possible through reuse of known exploits in computer systems that have not been fully eradicated; existing pieces of malware can be trivially modified and combined to create new malware, which is unknown to anti-virus programs. Finding new software with similarities to known malware is therefore an important goa...
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作者：Chan, Joshua; Leon-Gonzalez, Roberto; Strachan, Rodney W.
作者单位：University of Technology Sydney; National Graduate Institute for Policy Studies; University of Queensland
摘要：Factor models are used in a wide range of areas. Two issues with Bayesian versions of these models are a lack of invariance to ordering of and scaling of the variables and computational inefficiency. This article develops invariant and efficient Bayesian methods for estimating static factor models. This approach leads to inference that does not depend upon the ordering or scaling of the variables, and we provide arguments to explain this invariance. Beginning from identified parameters which a...
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作者：Chen, Kun; Mishra, Neha; Smyth, Joan; Bar, Haim; Schifano, Elizabeth; Kuo, Lynn; Chen, Ming-Hui
作者单位：University of Connecticut; University of Connecticut
摘要：Necrotic enteritis (NE) is a serious disease of poultry caused by the bacterium C. perfringens. To identify proteins of C. perfringens that confer virulence with respect to NE, the protein secretions of four NE disease-producing strains and one baseline nondisease-producing strain of C. perfringens were examined. The problem then becomes a clustering task, for the identification of two extreme groups of proteins that were produced at either concordantly higher or concordantly lower levels acro...
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作者：Li, Gen; Huang, Jianhua Z.; Shen, Haipeng
作者单位：Columbia University; Texas A&M University System; Texas A&M University College Station; University of Hong Kong
摘要：Telephone call centers offer a convenient communication channel between businesses and their customers. Efficient management of call centers needs accurate modeling of customer waiting behavior, which contains important information about customer patience (how long a customer is willing to wait) and service quality (how long a customer needs to wait to get served). Hazard functions offer dynamic characterization of customer waiting behavior, and provide critical inputs for agent scheduling. Mo...
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作者：Santacatterina, Michele; Bottai, Matteo
作者单位：Karolinska Institutet
摘要：Probability weights are used in many areas of research including complex survey designs, missing data analysis, and adjustment for confounding factors. They are useful analytic tools but can lead to statistical inefficiencies when they contain outlying values. This issue is frequently tackled by replacing large weights with smaller ones or by normalizing them through smoothing functions. While these approaches are practical, they are also prone to yield biased inferences. This article introduc...
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作者：Warnick, Ryan; Guindani, Michele; Erhardt, Erik; Allen, Elena; Calhoun, Vince; Vannucci, Marina
作者单位：Rice University; University of California System; University of California Irvine; University of New Mexico; University of New Mexico; University of New Mexico
摘要：Dynamic functional connectivity, that is, the study of how interactions among brain regions change dynamically over the course of an fMRI experiment, has recently received wide interest in the neuroimaging literature. Current approaches for studying dynamic connectivity often rely on ad hoc approaches for inference, with the fMRI time courses segmented by a sequence of sliding windows. We propose a principled Bayesian approach to dynamic functional connectivity, which is based on the estimatio...
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作者：Zhang, Anderson Y.; Zhou, Harrison H.
作者单位：Yale University
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作者：Zhou, Ling; Lin, Huazhen; Liang, Hua
作者单位：Southwestern University of Finance & Economics - China; Southwestern University of Finance & Economics - China; George Washington University
摘要：We consider the estimation of mean and covariance functions for longitudinal and sparse functional data by using the full quasi-likelihood coupling a modification of the local kernel smoothing method. The proposed estimators are shown to be consistent, asymptotically normal, and semiparametrically efficient in terms of their linear functionals. Their superiority to the competitors is further illustrated numerically through simulation studies. The method is applied to analyze AIDS study and atm...
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作者：Fattorini, L.; Marcheselli, M.; Pratelli, L.
作者单位：University of Siena
摘要：The estimation of the values of a survey variable in finite populations of spatial units is considered for making maps when samples of spatial units are selected by probabilistic sampling schemes. The single values are estimated by means of an inverse distance weighting predictor. The design-based asymptotic properties of the resulting maps, referred to as the design-based maps, are considered when the study area remains fixed and the sizes of the spatial units tend to zero. Conditions ensurin...
