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991.
Abstract . It is the purpose of this paper to examine critically the choice of “zero discharge” as me ultimate goal of our federal water pollution policy and to demonstrate that a goal of 90 percent removal of pollutants from effluents of urban areas will be more economically efficient. Our results indicate that in reaching “Zero discharge,” there is a minimal return in water quality for urban areas which are located on large bodies of water. The final conclusion is that the substantial resources, which would be required to surpass the level of 90 percent removal of pollutants, could be employed more effectively in other social programs. 相似文献
992.
This paper develops theory and algorithms for a “multiplicative” Data Envelopment Analysis (DEA) model employing virtual outputs and inputs as does the CCR ratio method for efficiency analysis. The frontier production function results here are of piecewise log-linear rather than piecewise linear form. 相似文献
993.
A bstract . Various factors explain human migration as it relates to the growth of cities. Some are closely related to the location of modem industry: people follow jobs or at least are attracted by better economic opportunities. Cities also attract population by a quality of life otherwise unavailable. Some move to particular cities for personal reasons, etc. But for the United States, at least, and for White migrants, two factors are also important in affecting migration decisions: White migrants are attracted by higher educational spending and lower property tax burdens relative to areas with lower spending and higher burdens. White migrants in 1960-70 apparently preferred areas with mild or warm climates but were less sensitive to income differences. 相似文献
994.
995.
Deborah C. Brown Thomas F. Curry Stephen C. Hoyle John H. Seader John J. Tomick Stephen T. Dziuban 《Socio》1992,26(4):241-255
Counternarcotics interdiction efforts have traditionally relied on historically determined sorting criteria or “best guess” to find and classify suspected smuggling traffic. We present a more quantitative approach which incorporates customized database applications, graphics software and statistical modeling techniques to develop forecasting and classification models. Preliminary results show that statistical methodology can improve interdiction rates and reduce forecast error. The idea of predictive modeling is thus gaining support in the counterdrug community. The problem is divided into sea, air and land forecasting, only part of which will be addressed here. The maritime problem is solved using multiple regression in lieu of multivariate time series. This model predicts illegal boat counts by behavior and geographic region. We developed support software to present the forecasts and to automate the process of performing periodic model updates. During the period, the model was in use at. Coast Guard Headquarters. Because of deterrence provided by improved intervention, the vessel seizure rate declined from 1 every 36 hours to 1 every 6 months. Due in part to the success of the sea model, the maritime movement of marijuana has ceased to be a major threat. The air problem is more complex, and required us to locally design data collection and display software. Intelligence analysts are using a customized relational database application with a map overlay to perform visual pattern recognition of smuggling routes. We are solving the modeling portion of the air problem using multiple regression for regional forecasts of traffic density, and discriminant analysis to develop tactical models that classify “good guys” and “bad guys”. The air models are still under development, but we discuss some modeling considerations and preliminary results. The land problem is even more difficult, and data collection is still in progress. 相似文献
996.
A bstract The Canada US Free Trade AGreement (FTA) which came into force January 1. 1989 caused heated debate within Canada about the impact it would have on social programs , other directly or indirectly It was argued that Canada would have to give up some social programs because they would be deemed to be substdues to the production of goods or services Alternatively, it was feared that firms would argue that the programs would need to be cut in order to ensure that they could compete with US firms in firms in terms of taxes It is shown that public unease about the fate of social programs was based both on a misunderstanding of FTA provisions, and on 'misperception'of the mag nitude of social program expenditures Social Programs Such as unemployment insurance , even when they subsidize particular groups of people (eg fisher men) are not normally deemed to be unfair competition which would be countervailable In addition, firsm do not expertence any greter benefit costs in Canada than in the US, albeit there is a different public/private split and thus there is no justification for firms to argue for cutting programs in order tobe competitive, other things being equal 相似文献
997.
"This paper examines the determinants of regional migration [in the United States] in the 1980s using a place-to-place migration model in which migration flows depend upon the relative economic opportunities in the origin and destination regions. Using the results of the model, we then examine the potential role for migration in diffusing the economic pressures associated with disparate regional economic growth. Although the results reinforce the notion that divergent regional growth was an impetus to migration in the 1980s, estimates of the employment status of movers suggest that the true effects of migration on unemployment differentials may be quite small." 相似文献
998.
A bstract . While previous studies on the unemployment-crime hypothesis have yielded equivocal results, here nonsignificant Pearson correlation coefficients were found for theft rates and the percentage of unemployed men and unemployed women for 20 nations. This raises additional cross-cultural questions about the validity both of strain theories that predict positive correlations, and competing theories that predict negative correlations. Implications for research on the unemployment-crime hypothesis are discussed. 相似文献
999.
Distance in organizations 总被引:1,自引:0,他引:1
There is perhaps no construct that is so fundamental to interpersonal interactions in organizations, yet so incompletely understood, than distance. Part of the difficulty in developing a comprehensive and informed understanding of the role distance plays in organizations is that theory and research in this area have been quite fragmented, focusing on narrow aspects of the construct and lacking the integration necessary to build a more general knowledge base. For example, Graen (1976) has contributed greatly to our understanding of one aspect of distance, presenting a model based on role theory whereby in-group and out-group members are hypothesized to enjoy different rewards, benefit from different leadership behaviors, and experience different levels of satisfaction and performance ratings based on relative closeness (or distance) in their working relationship with their supervisor. Other researchers have explored the phenomena of psychological distance (Rothaus, Morton, & Hanson 1965), spatial distance (Kerr & Jermier 1978; Ferris & Rowland 1985), and physical distance (Sundstrom, Burt, & Kamp 1980; Sundstrom 1986) in the supervisor-subordinate relationship. This research, although a good starting point, does not adequately define or integrate the various aspects of distance in organizations. This article represents an effort to develop a broader and more extensive understanding of the role distance plays in organizations by integrating the various types of distance into a theoretical model. A model of Dyadic Distance in the supervisor-subordinate relationship is presented which develops the new constructs of Dyadic, Psychological, Structural, and Functional Distance, examines their process dynamics and impact on Human Resource Management issues such as performance evaluations and turnover, and proposes needed directions for future research in this important area. 相似文献
1000.
Manfred J. Holler 《Quality and Quantity》1988,22(3):279-292
In this paper strategic situations of voting and abstentions are analysed in a three-candidate voting model where voters are indifferent to various alternatives and candidates are interested in winning the election and seeing their most preferred alternative being realized. A specific decision problem is analysed, described by an Indifference Trap Game, with respect to, e.g., the corresponding Nash equilibria, perfect equilibria, and maximin solution. A second-best outcome is contained in the choice set of all three solutions while the Nash equilibrium concept is compatible with the Pareto efficient outcomes of the game.An alternative scenario where candidates suffer from incumbency but voters still are indifferent to some alternatives also supports the second-best outcome. Again, various solutions concepts are applied. We conclude that indifferent voters imply an eminent coordination problem for the candidates in the given voting game which, in general, ends up in inefficient outcomes. The inherent complexity of the decision situation cannot be sufficiently reduced to single out one and only one outcome. 相似文献