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991.
Since most agricultural programs employ two or more policy instruments simultaneously, it is notable thai little research has attempted to find optimal instrument combinations and no research exists which evaluates the social costs (unrealized benefits) of combining instruments suboptimally. In our paper we report a simple and feasible method to find optimal policy instrument combinations, and we provide the first general, formal approach to measuring the social costs of suboptimal policy instrument combinations. Our approach is illustrated in an analysis for live major U.S. crops (corn, feed grains, wheat, rice, cotton). The simple model we employ for the illustration suggests that except lor the feed grains program, the observed programs combined policy instruments quite suboptimally. We conclude that agricultural economics research now can and should begin placing increased emphasis on studying optimal policy instrument combinations.  相似文献   
992.
There are a number of significant environmental impacts that arise from agricultural practices that may be influenced by policy. A Strategic Environmental Assessment Method (SEAM) is described which aims to assess the environmental impacts of agricultural policy and aid the development of more sustainable policy formulation. The method addresses the issues of selecting appropriate performance criteria and measurements, and makes use of effect-damage functions and targets to determine the significance of potential impacts in relation to sustainability. A set of profiles is produced, describing the environmental performance of a specific policy. A confidence assessment system (CAS) is also described which provides details about the quality of the assessment and areas of uncertainty. SEAM provides information about impacts in simple format that can be easily used in decision making. It can identify environmental trade-offs and provides a holistic view that is essential when making decisions that affect the environment.  相似文献   
993.
994.
Perhaps the most common criticism of socially responsible investment funds is that imposing non‐financial screens restricts investment opportunities, reduces diversification efficiencies and thereby adversely impacts performance. In this study we investigate this proposition and test whether the number of screens employed has a linear or curvilinear relation with return. Moreover, we analyse the link between screening intensity and risk. Screening intensity has no effect on unadjusted (raw) returns or idiosyncratic risk. However, we find a significant reduction in α of 70 basis points per screen using the Carhart performance model. Increased screening results in lower systematic risk – in line with managers choosing lower β stocks to minimize overall risk.  相似文献   
995.
The exact forms of the locally minimum variance unbiased estimators and their variances are given in the case of a discontinuous density function.  相似文献   
996.
The purpose of this article is to explore the impact of seller’s reputation and promotional methods on auction outcomes in the Finnish online auction website, Huuto.net. Multiple linear and logistic regression analyses are used to test a set of hypotheses. The dataset consists of 227 auctions of iPhone 4S 16 GB mobile phones posted for auction by 138 individual sellers. The main finding is that sellers who have acquired a free identification from Huuto.net achieve a hefty increase in the final sales price. Sellers who have not established an online reputation achieve considerably lower closing prices at auction. An increase in negative feedback points reduces the final sales price. Purchasing display-enhancing promotional options does not increase the price but may improve probability of sale. Establishing reputation, avoiding negative feedback, and acquiring identification pay off. The promotional options associated with fonts and colors are not worth the cost.  相似文献   
997.

It has been acknowledged in the literature that productive efficiency in grain production in China has substantially improved in the post-reform period, particularly in the early 1980s. Since then, there have been several policy changes in China, which have affected the growth of the sector. Specifically, the spectacular growth of rural industries has attracted significant physical and human capital from agriculture. It is in this context that Brown's warning of China soon becoming the world's number one importer of grain has raised an important question of whether China has reached its grain production potential. Analysis of the 1994 farm household survey data indicates that the majority of the sample farmers is reasonably technically efficient in grain production but that productivity can be increased further even with the existing technology.  相似文献   
998.
The sub-Saharan Africa challenge programme is designed to address the problems of failures of agricultural markets, inappropriate policies and natural resource degradation, that contribute to the continuing deterioration of livelihoods and food security in the region. It is seeking to do this by redefining the roles of scientists and farmers through collaborative learning processes, addressing questions about the level, timing, type and formof participation, as well as themost effective approaches andmethods to foster them. The research domains of the programme deal with sustainable intensification of smallholder agriculture, the sustainable management of natural resources, the development of efficient markets, and the promotion of enabling policies. One question that was addressed in designing the initiative was deciding where to work so as to maximize the chances of successful testing of this new approach, so that it would lead to significant reductions of rural poverty. A participatory process was put in place to design a framework to accomplish this site selection, and then to apply it in west, east and southern Africa. A mixture of spatial data analysis and expert knowledge on spatial and non-spatial factors was used, and one primary site in each region was identified to form the basis for the next phase of the challenge programme. Several lessons were learnt from the process, including the importance of adapting themethods to actual conditions, the increased utility of targetting when the quantitative and the qualitative are freely combined, and the continued need for baseline spatial and non-spatial data to improve the targeting of research in the future that is designed to alleviate poverty in sub-Saharan Africa.  相似文献   
999.
In Maasai culture, responsibilities are traditionally divided between genders. Men are in charge of grazing and managing the livestock herds. Women take care of the family, administer food supplies, and are responsible for milking. For them, balancing home consumption of milk (for the family and for the calves), milk sale, and food purchase is a major task. In this article, we first investigate how different milk sales groups vary regarding the use of different food items and the respective quantities consumed by the enkaji, i.e., a Maasai subhousehold. Then, we address the commercialization decision and assess the effect of milk sales on the enkaji's food item use and food consumption. Using the data of Maasai enkajijik in the milk catchment area of a milk collection center in Ngerengere, Tanzania, we estimate the effects by employing propensity score matching procedures. Our findings suggest that milk sellers, especially those selling to the milk collection center, have a more diverse diet. In terms of per person consumption, the groups are markedly similar. Therefore, we conclude that income generated by milk sales is invested in diet diversification rather than in increasing the quantity of food consumed, hence the enkajijik appear not to make use of caloric terms of trade.  相似文献   
1000.
The last three decades have witnessed the continued exit of households from primary agriculture in the United States, where the average annual gross exit rate has averaged 10% per year. Understanding exit behavior is one key to future farm structure, management of abandoned land, depopulation of rural areas, and agricultural policy, including government program payments. This study empirically estimates the determinants of exit decisions of farm households. Particular attention is given to the roles of intensity of government payments and off‐farm work decisions of farm couples in the exit decision. Using a large farm‐level survey and controlling for endogeneity, results indicate that farm households with reduced intensity of government payments are more likely to exit farming. Households where the operator spouse works off the farm are more likely to exit farming. Additionally, households with older farmers, with the farm operator and spouse raised on a farm, and households operating farms located in Northern Great Plains are more likely to exit farming.  相似文献   
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