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901.
Predicting the geo-temporal variations of crime and disorder   总被引:2,自引:0,他引:2  
Traditional police boundaries—precincts, patrol districts, etc.—often fail to reflect the true distribution of criminal activity and thus do little to assist in the optimal allocation of police resources. This paper introduces methods for crime incident forecasting by focusing upon geographical areas of concern that transcend traditional policing boundaries. The computerised procedure utilises a geographical crime incidence-scanning algorithm to identify clusters with relatively high levels of crime (hot spots). These clusters provide sufficient data for training artificial neural networks (ANNs) capable of modelling trends within them. The approach to ANN specification and estimation is enhanced by application of a novel and noteworthy approach, the Gamma test (GT).  相似文献   
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This paper defines business ethics as a seriesof behaviors that adhere to values held by theindividual manager, the manager's supervisorsand subordinates, general society and, mostimportantly, the manager's customers andclients. The concept of business ethics isexplored through several levels of businessorganizations and operating environments.The paper then examines recent evidence of thedecline in business ethics by noting a fewexamples involving Beech-Nut, Hertz, MichaelMilken, E.F. Hutton, Sears, Salomon Brothers,Dalkon Shield, Exxon Valdez, S&L scandal,brokerage analysts. Surveys are cited toindicate that the American public believes thatbusiness ethics are declining.To further analyze the topic, the authorreports on a series of structured interviewswith managers in a variety of organizations.Fourteen senior managers were interviewed: 4from large county government, 3 from stategovernment, 4 from large corporations, 3 fromsmall businesses. The managers were asked theiropinions concerning the decline of businessethics, and for their recommendations topossibly retard the decline. All managers saidthey believed that ethics are in decline andthat the public believes ethics are declining.The recommendations for retarding or reversingthe decline yielded several suggestions: teachethics in schools and business organizations,develop and enforce Codes of Ethical Conductwithin all organizations, establish bettermonitoring and reporting mechanisms, and hireethical managers.The paper builds on theinterview results by coupling the managers'remarks with admonitions from many authors:while teaching ethics and Codes of EthicalConduct are important, the most importantfactor is the ethical behavior of managers(leaders). Ethical leadership is fundamentalsince ethical behavior is an individual – not acorporate – matter. In practice, ethics is notsomething that a manager ``does'; it issomething that the manager ``is.'  相似文献   
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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   
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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   
910.
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   
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