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71.
Warmer temperatures and a decrease in precipitation in the 21st century could severely deplete wetlands in the prairie pothole region of western Canada. In this study, we employ linear regression analysis to determine the casual effect of climate change on wetlands in this region, with temperature, precipitation and the standardized precipitation index (SPI) used to predict the effect of potential climate change on wetlands. We then use a waterfowl-wetlands bioeconomic model to solve for socially optimal levels of duck harvests and wetlands retention under current climate conditions and various climate change scenarios. The model maximizes benefits to hunters plus the amenity values of ducks to non hunters and the non-market ecosystem benefits of wetlands. Results indicate that climate change could decrease wetlands by between 7 and 47%, and that the optimal number of wetlands to retain could decrease by as much as 38% from the baseline climate.  相似文献   
72.
The relationship between bio-energy feedstock production and water quality has received little attention from economists. Here, an optimal control model is used to determine the optimal amount of land to convert to the production of energy feedstocks, specifically ethanol corn, taking into account potential impacts on water quality. Based on comparative static analyses of an optimal control model, and a numerical application, we find that the optimal proportion of land to shift into bio-energy production from a baseline use, such as the Conservation Reserve Program, depends on key model parameters, specifically the rate of degradation of the pollutant and the link between the intensity of bio-energy feedstock production and the rate of change in the pollutant stock. Yet, there is a limit to how much land should optimally be converted as society must trade-off its desire to mitigate climate change against its willingness to accept a decline in water quality. Le lien entre la production de matières premières bioénergétiques et la qualité de l’eau a attiré peu d’attention de la part des économistes. Nous avons utilisé un modèle de contrôle optimal pour déterminer les superficies optimales à convertir à la production de matières premières énergétiques, en particulier le maïs destinéà la production d’éthanol, en tenant compte des répercussions potentielles sur la qualité de l’eau. D’après une simulation numérique et des analyses de statique comparative obtenues à l’aide d’un modèle de contrôle optimal, nous en sommes venus à la conclusion que les superficies optimales à convertir à la production de matières premières bioénergétiques à partir d’un instrument de référence, tel que le Conservation Reserve Program (Programme de réserve des terres sous conservation), dépend des paramètres clés du modèle, particulièrement du taux de biodégradation des polluants et du lien entre l’intensité de la production de matières premières bioénergétiques et le taux de variation du stock de polluants. Il existe tout de même une limite quant aux superficies à convertir étant donné que la société doit faire un choix entre son désir d’atténuer le changement climatique et son acceptation d’une diminution de la qualité de l’eau.  相似文献   
73.
Conservation Payments under Risk: A Stochastic Dominance Approach   总被引:2,自引:0,他引:2  
Conservation payments can be used to preserve forest and agroforest systems. To explain landowners' land-use decisions and determine appropriate conservation payments, it is necessary to focus on revenue risk. Marginal conditional stochastic dominance rules are used to derive conditions for determining the conservation payments required to guarantee that the environmentally preferred land use dominates. An empirical application to shaded coffee protection in the biologically important Chocó region of West Ecuador shows that conservation payments required for preserving shaded coffee areas are much higher than those calculated under risk-neutral assumptions. Further, the extant distribution of land has strong impacts on the required payments.  相似文献   
74.
The middle class of Vietnam is growing and so is their consumption, especially in urban areas. This is due to the effects of rapid economic growth, industrialization and increasing wealth in combination with a young, growing population. This paper aims to understand current consumption patterns and consumption categories that can provide a start for sustainable lifestyles among the Vietnamese middle class. Data was collected in the capital Hanoi, in the north of Vietnam. The current level of awareness, knowledge and attitude was explored on five specific consumption topics: energy, transport, water, waste, and food. A combination of quantitative and qualitative data was collected: 5 focus groups, 5 in‐depth interviews and a survey among 158 Vietnamese urban middle class consumers. The results are discussed according to the MOA model that explains behaviour as a function of three components: Motivation, Opportunity and Ability. The research concludes that awareness and knowledge of the urban middle class in Vietnam on sustainable consumption is generally low. However, the motivation to live healthy lifestyles and protect the planet for their future generations is rather high. In order to support more sustainable lifestyles, the awareness of environmental issues needs to be increased; knowledge needs to be made available and accessible (ability); and role models need to set an example for the urban middle class of Vietnam. Furthermore, health in combination with food is the most important reason for people to pursue a sustainable lifestyle (motivation) and the need to change was expressed. However, a general distrust towards business and governmental actors was also found. Therefore, opportunities for bottom‐up initiatives for sustainable food consumption must be explored in the future. This could support in engaging the middle class of Vietnam in sustainable lifestyles.  相似文献   
75.
In this study, a dichotomous choice model is used to determine the compensating welfare measure for water quality improvements stemming from livestock waste management in the Abbotsford region of southwestern British Columbia. The benefits of improving water quality are compared with the net costs of composting manure on a large scale, the option for handling livestock wastes preferred by the provincial government. The results indicate that the costs of composting manure exceed the revenue from selling manure (compost) plus the off-site damages avoided.  相似文献   
76.
In seeking to value environmental amenities and public goods, individuals often have trouble trading off the (vague) good or amenity against a monetary measure. Valuation in these circumstances can best be described as fuzzy in terms of the amenity being valued, perceptions of property rights, and the numbers chosen to reflect values. In this paper, we apply fuzzy logic to contingent valuation, employing a fuzzy clustering approach for incorporating preference uncertainty obtained from a follow-up certainty confidence question. We develop a fuzzy random utility maximization (FRUM) framework where the perceived utility of each individual is fuzzy in the sense that an individual’s utility belongs to each cluster to some degree. The model is then applied to a Swedish survey that elicited residents’ willingness to pay for enhanced forest conservation and to a Canadian survey of agricultural landowners that elicited their willingness to accept compensation for a tree planting program. Both the WTP and WTA measures we obtain using the fuzzy approach are well below those obtained using standard probability methods. Based on goodness of fit measures and Monte Carlo experimentation, a case can be made for using a fuzzy preference approach for modeling preference uncertainty as opposed to incorporating respondent uncertainty within the random utility maximization framework.   相似文献   
77.
To mitigate the adverse effects of reduced access to public forage, ranchers may require financial or other forms of "compensation." In this paper, we use results from a survey of Nevada ranchers to examine their willingness to sell grazing permits and participate in other schemes that enable them to continue ranching in spite of declining access to public forage. On average, ranchers demand $255 per animal unit month to sell grazing permits, while support for other programs, some of which are performance based, depends on whether respondents trust public agencies and intend to pass their ranch onto an heir.  相似文献   
78.
79.
This research examines the impact of uncertainty on contingent valuation responses using (1) a survey of Canadian landowners about willingness to accept compensation for converting cropland to forestry and (2) a survey of Swedish residents about willingness to pay for forest conservation. Five approaches from the literature for incorporating respondent uncertainty are used and compared to the traditional random utility model with assumed certainty. The results indicate that incorporating uncertainty has the potential to increase fit, but could introduce additional variance. While some methods for uncertainty can be an improvement over traditional approaches, it is imperative to exercise caution when making systematic judgments about the effect of uncertainty on contingent valuation responses.  相似文献   
80.
Summary This paper deals with the problem how to measure the degree of inequality implied by a certain distribution of personal incomes. Traditional approaches to this subject, including statistical and welfare-based indicators, possess some important short-comings. As an alternative procedure this paper proposes the use of explicit normative concepts, by defining indicators which measure the divergence between an actual income distribution and a target or desirable one. Several indicators are given. The problem how to specify a target distribution is discussed, and a tractable procedure is indicated. This is applied to both actual and simulated income data. The examples serve only as illustrations of the approach proposed and use of the indicators for actual policy evaluation still requires more data.The author wishes to thank Henk van Metelen and Arend Stemerding for research assistance, and Simon Kuipers, Peter Nijkamp and Jan Tinbergen for their stimulating remarks on an earlier draft of this paper. Of course, they are not responsible for errors and do not necessarily share the opinion expressed in this paper. This paper has been presented at the Econometric Society European Meeting, Helsinki, August 1976. An extensive discussion of different aspects of income distribution is contained in Bartels (1977).  相似文献   
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