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81.
Multinomial Logit Model has analyzed the relationship between the frequency of visits to recreation areas and the motivational factors affecting the visits. Kastro Environment Preserving Site that is located in the Black Sea coast of Marmara region in Turkey, has been chosen as the site for this study. Kastro bay is a natural park that is visited only for recreational visits. The study has been conducted on a photogenic study group due to the proximity factor of Kastro bay close to Istanbul. Kastro bay is a popular recreational park due to its characteristic advantages such as a 200 m wide and approximately 2.5 km long beach and with its high quality vegetation. The vegetation type includes ash tree, oak tree, black pine, sand lily etc. Kastro bay is also the site for the Mediterranean seals (Monachus-monachus) which are at the level of extinction. Approximately 50,000 visitors visit the region during the months of July and August. It has been concluded that there is high direct correlation between the frequency of visits and the motivational factors. It has been determined that the visits are mostly based on the sea and the ecological tourism.Jel: O13, Q20, Q26, Q51, Q56, Q57  相似文献   
82.
83.
Seven computerprograms for non-linear regression or curve fitting problems are compared. The comparison of the programs, running in different computing centra, is restricted to the fit performance. Six model functions are fitted according to the least squares criterion to data series, arising from practical work. The special least squares minimization programs turned out to be better suited for these problems than general optimizing programs.  相似文献   
84.
A Stochastic Frontier Production Function with Flexible Risk Properties   总被引:1,自引:1,他引:1  
This paper considers a stochastic frontier production function which has additive, heteroscedastic error structure. The model allows for negative or positive marginal production risks of inputs, as originally proposed by Just and Pope (1978). The technical efficiencies of individual firms in the sample are a function of the levels of the input variables in the stochastic frontier, in addition to the technical inefficiency effects. These are two features of the model which are not exhibited by the commonly used stochastic frontiers with multiplicative error structures.An empirical application is presented using cross-sectional data on Ethiopian peasant farmers. The null hypothesis of no technical inefficiencies of production among these farmers is accepted. Further, the flexible risk models do not fit the data on peasant farmers as well as the traditional stochastic frontier model with multiplicative error structure.  相似文献   
85.
Selection and execution of site decontamination projects is often best left to local authorities, in accordance with the subsidiarity principle, even though the budget for such projects is made available through a central authority. In this paper we suggest a practical budget allocation policy which a central authority can employ to allocate budgets to local authorities, while still optimising the central authority's environmental objective function. The procedure is fully consistent with the principle of decentralisation of responsibility for selection and execution of projects, and requires a minimum information exchange between local and central levels. Despite the information asymmetry between local and central levels, incentive compatibility problems can be (partially) prevented by choosing an appropriate evaluation mechanism. At the same time, the procedure is computationally effective and efficient, and can guarantee a fair budget allocation, making it easy to implement and politically acceptable.  相似文献   
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87.
This paper examines differences in earnings by occupations, and within occupations by sex and by race, on the basis of the 1/100 Public Use Samples of the 1960 and 1970 U.S. Population Censuses. It employs interval analysis to establish 32 categories of occupations with similar characteristics. Little relation was found between mean earnings of occupational groups and the degree of earnings inequality within them. When the figures are examined by sex, it was found that men, on average, earned over twice as much as women in both years, but women's earnings were more unequally distributed (as measured by the Gini coefficient). Women are concentrated in the traditional “female” occupations, which tend to be those at the bottom of the earnings scale, and men have a monopoly of the higher paid occupations. But mean earnings for men exceeded those for women in all occupational groups except one, even in the primarily female occupations. Standardizing first for occupational distribution and then for earnings by occupation, it was found that earnings differences between males and females within occupation had a greater impact on the overall male-female earnings ratio than did differences in occupational distribution by sex. In contrast, when the figures are examined by race, the change in occupational distribution (primarily the movement of blacks out of farming and of blacks and Spanish speakers out of personal services) was the major factor. There was also a considerable degree of earnings inequality within demographic groups. The degree of inequality was in the main reduced when the demographic groups were subdivided into occupations, but it was still substantial. Additional factors like time worked, schooling, and experience must be taken into consideration in understanding this phenomenon.  相似文献   
88.
In questo lavoro viene fornita una nuova caratterizzazione dell'ammissibilità attraverso un adeguato uso della nozione di ammissibilità parziale. Questa caratterizzazione consente di affrontare le questioni riguardanti la completezza della classe delle decisioni ammissibiliti sotto condizioni «maneggevoli». Fornisce inoltre un approccio unificante al problema della completezza che consente di derivare, come casi particolari, alcuni risultati già noti nella letteratura sull'argomento.
In this paper a new characterization of admissibility is given for general decision problems. It is based on an adequate use of the notion of partial admissibility.A general decision problem is usually synthetized by a triplet (, , ) where is the states (or parameters) space, the set of available decisions and is a family of real valued functions defined on and expressing numerically the consequences of choosing when the state is . The set is regarded as a subset of the space of all real valued functions on endowed with the topology of pointwise convergence.As for as admissibility is concerned all the pertinent information about decisions are contained in the corresponding functionsW .This allows to introduce a notion of partial admissibility through the neigh-bourhoods of this topology. Admissibile decisions are then shown to be limits of monotone non increasing sequences of partially admissible decisions.Moreover this topological characterization allows to prove the completeness of classes of admissible decisions under acceptable systems of conditions which contain as special cases, known results in literature.


Lavoro svolto nell'ambito del Gruppo Nazionale per l'Analisi Funzionale e le sue Applicazioni del C.N.R.  相似文献   
89.
We construct a laboratory market in which there is a friction in the matching between buyers and sellers. Sellers simultaneously post prices and then buyers simultaneously choose a seller. If more than one buyer chooses the same seller, the seller's single unit is randomly sold to one of them. Our results show a broad consistency with theoretical predictions, although price dispersion exists and is slow to decay. Prices also exceed the equilibrium level when there are only two sellers, and buyers' purchase probabilities are insufficiently responsive to price differences when there are two sellers.  相似文献   
90.
A bstract . In the eyes of European scholars, publicists and politicians who studied Henry George's work, he, as a social philosopher , had adopted the position of the natural law philosophers of the 18th century. The latter inspired the Declaration of Independence, the U.S. Constitution and its Bill of Rights, as well as the poiitical philosophy of Jeffersonian democracy , the ethos of the 18th and 19th century pioneer settlers. George rejected Social Darwinism. He saw natural law as the only true and reliable basis for a just social order. Like Karl Marx he mastered Ricardian economics ; unlike Marx, George made two factors the basis of his system, labor and land. George saw that each person had a natural right —and a natural imperative for survival —to apply his or her productive capacity to the earth –as living space and as storehouse of nutrients and raw materials. The person-land relationship , he discovered, lay at the basis of human culture. And so the land's rent , now monopolized by the few, had to be appropriated to meet the needs of society, most efficiently and justly by a land value tax.  相似文献   
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