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作者：Mittelhammer, R; Judge, G; van Akkeren, M; Cardell, NS
作者单位：Washington State University; Washington State University; University of California System; University of California Berkeley; University of California System; University of California Berkeley
摘要：In the context of a semiparametric regression model with underlying probability distribution unspecified, an extremum estimator formulation is proposed that makes use of empirical likelihood and information theoretic estimation and inference concepts to mitigate the problem of an ill-conditioned design matrix. A squared error loss measure is used to assess estimator performance in finite samples. In large samples, the estimator can be designed to be consistent and asymptotically normal, so tha...
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作者：Gotway, CA; Young, LJ
作者单位：Centers for Disease Control & Prevention - USA; University of Nebraska System; University of Nebraska Lincoln
摘要：Global positioning systems (GPSs) and geographical information systems (GISs) have been widely used to collect and synthesize spatial data from a variety of sources, New advances in satellite imagery and remote sensing now permit scientists to access spatial data at several different resolutions. The Internet facilitates fast and easy data acquisition. In any one study, several different types of data may be collected at differing scales and resolutions, at different spatial locations, and in ...
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作者：Sherman, M
作者单位：Texas A&M University System; Texas A&M University College Station
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作者：Eide, AL; Omre, H; Ursin, B
作者单位：Norwegian University of Science & Technology (NTNU); Norwegian University of Science & Technology (NTNU)
摘要：Offshore petroleum reservoirs are usually explored by acquisition of vast amounts of seismic reflection data and observations along a small number of wells drilled through the reservoirs. The seismic data a-re indirect measurements of reservoir characteristics and have good spatial coverage but low precision. The A ell observations are sparse but precise. Information from these sources of data are integrated to characterize the reservoir variables of interest-reservoir porosity in the current ...
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作者：Liang, F
作者单位：National University of Singapore
摘要：This article describes a new Monte Carlo algorithm, dynamically weighted importance sampling (DWIS), for simulation and optimization. In DWIS, the state of the Markov chain is augmented to a population. At each iteration, the population is subject to two move steps, dynamic weighting and population control. These steps ensure that DWIS can move across energy barriers like dynamic weighting, but with the weights well controlled and with a finite expectation. The estimates can converge much fast...
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作者：Kanaan, MN; Farrington, CP
作者单位：Open University - UK
摘要：Whether the protection afforded by a vaccine wanes over time and if so, by how much, are important public health questions with implications for mass immunization programs. However, the measurement of such effects is fraught with difficulties. Generally, clinical trials are too short to provide evidence on waning effects. Thus it is necessary to rely on epidemiologic data, which are subject to ascertainment bias. Furthermore, standard epidemiologic, measures, such as hazard ratios, may not acc...
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作者：Newman, KB; Rice, J
作者单位：University of Idaho; University of California System; University of California Berkeley
摘要：To study the factors associated with the freshwater mortality of outmigrating chinook salmon, releases of tagged juvenile salmon were made at multiple locations in the Sacramento River each spring between the years 1979 and 1995. A midwater trawl located downstream of the release sites caught salmon soon after release and, 1 to 4 years later, samples taken from the catches of marine fisheries recovered other tagged fish. An extended quasi-likelihood model was fit to both the freshwater and the...
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作者：Shen, XT; Huang, HC; Cressie, N
作者单位：University System of Ohio; Ohio State University
摘要：Nonparametric hypothesis testing for a spatial signal can involve a large number of hypotheses. For instance,, two satellite images of the same scene, taken before and after an event, could be used to test a hypothesis that the event has no environmental impact. This is equivalent to testing that the mean difference of after-before is zero at each of the (typically thousands of) pixels that make up the scene. In such a situation, conventional testing procedures that control the overall type I ...
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作者：Christensen, WF; Amemiya, Y
作者单位：Southern Methodist University; Iowa State University
摘要：Multivariate spatial or geo-referenced data arise naturally in such disciplines as ecology, agriculture, geology, and atmospheric sciences. In practice, interest often lies in modeling underlying structure and representing interrelationships in terms of a smaller number of variables. For such situations, statistical analysis using a latent variable model is proposed. We present a general model that incorporates spatial correlation and potential lagged or shifted dependencies and that can repre...
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作者：Barsky, R; Bound, J; Charles, KK; Lupton, JP
作者单位：University of Michigan System; University of Michigan; Federal Reserve System - USA; Federal Reserve System Board of Governors
摘要：Many applications involve a decomposition of the mean intergroup difference in a given variable into the portion attributable to differences in the distribution of one or more explanatory variables and that due to differences in the conditional expectation function. This article notes two interrelated reasons why the Blinder-Oaxaca (B-O) method-the approach most commonly used in the literature-may yield misleading results. We suggest a natural solution that both provides a more reliable answer...
