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901.
902.
The truncated Poisson regression model is used to arrive at point and interval estimates of the size of two offender populations, i.e. drunk drivers and persons who illegally possess firearms. The dependent capture–recapture variables are constructed from Dutch police records and are counts of individual arrests for both violations. The population size estimates are derived assuming that each count is a realization of a Poisson distribution, and that the Poisson parameters are related to covariates through the truncated Poisson regression model. These assumptions are discussed in detail, and the tenability of the second assumption is assessed by evaluating the marginal residuals and performing tests on overdispersion. For the firearms example, the second assumption seems to hold well, but for the drunk drivers example there is some overdispersion. It is concluded that the method is useful, provided it is used with care.  相似文献   
903.
904.
A bilinear multivariate errors-in-variables model is considered. It corresponds to an overdetermined set of linear equations AXB=C, A∈ℝm×n, B∈ℝp×q, in which the data A, B, C are perturbed by errors. The total least squares estimator is inconsistent in this case.  An adjusted least squares estimator is constructed, which converges to the true value X, as m →∞, q →∞. A small sample modification of the estimator is presented, which is more stable for small m and q and is asymptotically equivalent to the adjusted least squares estimator. The theoretical results are confirmed by a simulation study. Acknowledgements. We thank two anonymous reviewers for their suggestions and corrections.? A. Kukush is supported by a postdoctoral research fellowship of the Belgian office for Scientific, Technical and Cultural Affairs, promoting Scientific and Technical Collaboration with Central and Eastern Europe.? S. Van Huffel is a full professor with the Katholieke Universiteit Leuven.? I. Markovsky is a research assistant with the Katholieke Universiteit Leuven.? This paper presents research results of the Belgian Programme on Interuniversity Poles of Attraction (IUAP V-22), initiated by the Belgian State, Prime Minister's Office – Federal Office for Scientific, Technical and Cultural Affairs of the Concerted Research Action (GOA) projects of the Flemish Government MEFISTO-666 (Mathematical Engineering for Information and Communication Systems Technology), of the IDO/99/03 project (K.U. Leuven) “Predictive computer models for medical classification problems using patient data and expert knowledge”, of the FWO projects G.0078.01, G.0200.00, and G0.0270.02.? The scientific responsibility is assumed by its authors.  相似文献   
905.
During the period of 1992 to 1996, the cable television industry in the United States was regulated by the FCC, which took several price cap measures. As a result, the increase in the price cable service substantially slowed. However, the cable demand did not rise as anticipated. Using a model of imperfectly discriminating monopoly, the paper empirically investigates this curious phenomenon of stagnant demand despite lower prices. The paper finds that the FCC's price capping constrained both demand and prices. The demand was constrained since the price cap was designed to cover almost all TV channels carried by cable systems, and subsequently discouraged cable systems from meeting different customer preferences with multi-tier services.  相似文献   
906.
This article matches establishment-level data on workplace transformation (e.g., quality circles, work teams, and just-in-time production) with measures of cumulative trauma disorders at these same establishments to explore the relationship between "flexible" workplace practices and workplace health and safety. The results reveal a positive, statistically significant, and quantitatively sizable relationship between cumulative trauma disorders and the use of quality circles and just-in-time production.  相似文献   
907.
Bayesian multiple imputation (MI) has become a highly useful paradigm for handling missing values in many settings. In this paper, I compare Bayesian MI with other methods – maximum likelihood, in particular—and point out some of its unique features. One key aspect of MI, the separation of the imputation phase from the analysis phase, can be advantageous in settings where the models underlying the two phases do not agree.  相似文献   
908.
In-depth data analysis plus statistical modeling can produce inferentialcausal models. Their creation thus combines aspects of analysis by close inspection,that is, reason analysis and cross-tabular analysis, with statistical analysis procedures,especially those that are special cases of the generalized linear model (McCullaghand Nelder, 1989; Agresti, 1996; Lindsey, 1997). This paper explores some of the roots of this combined method and suggests some new directions. An exercise clarifies some limitations of classic reason analysis by showing how the cross tabulation of variables with controls for test factors may produce better inferences. Then, given the cross tabulation of several variables, by explicating Coleman effect parameters, logistic regressions, and Poisson log-linear models, it shows how generalized linear models provide appropriate measures of effects and tests of statistical significance. Finally, to address a weakness of reason analysis, a case-control design is proposed and an example is developed.  相似文献   
909.
Generally valid scientific explanations of observable social phenomena are still hardly available. By applying philosophical insights generated by Quine and derived from semiotics to social research methodology three kinds of context dependencies accompanying theory formation within social science are identified. The third context dependency is mostly not attended in theory formation about social phenomena thereby producing a ``connotation fallacy', which leaves almost all social theories undetermined and fallible. These context dependencies should be taken into account in the research design and be tested for using statistical criteria comprising a new methodology presented in this article.  相似文献   
910.
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