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991.
India's agricultural research spending has long been regionally uneven. Regional research intensity ratios, which account for size differences, indicate research spending has consistently favored southern and western states over northern, central, and eastern ones. Farm production patterns have, however, changed in recent years and regional output growth is being driven by new commodity mixes. In this article, we ask which region had the highest factor productivity growth and rate of return to investments in public agricultural research and higher education. Our analysis relies on a 1980–2008 Indian agricultural production and policy data set together with a dual heteroscedastic production frontier to decompose total factor productivity (TFP) growth into formal technical progress and efficiency elements. The model's regional flexibility affords region‐to‐region comparison of multiple research return rates, TFP growth, and the elements influencing them. Regardless of return‐rate measure or allocation scenario evaluated, the North has enjoyed the highest return to research spending, and the Central and East the lowest. Factor productivity growth has however been strongest in the South, primarily on account of efficiency gains. Overall, though, the technical progress and productivity growth easily attributable to government‐supported research has accounted for about one‐quarter of the sector's TFP growth.  相似文献   
992.
The farmer share of retail prices is shown to be about 16%, corresponding to about 84% of a distribution share, on average across agricultural products and regions within Turkey. The share of transportation costs in retail prices is only about 7%, while the share of retail margins is about 77% of retail prices. The dispersion of retail prices across regions is shown to be mostly due to local wages and variable markups, while the contribution of traded‐input prices is relatively small. Accordingly, the high dispersion of farmer prices across locations is not reflected in the dispersion of retail prices due to the high contribution of retail margins. These retail margins are also shown to account for about one third of the consumer welfare dispersion across regions and more than half of the consumer welfare dispersion across products.  相似文献   
993.
Efficiency, partly based on technology, is central to international competitiveness. This article applies a stochastic frontier inefficiency model to a panel of 77 wine grape farms in South Africa between 2005 and 2015 and allows the comparison of efficiency levels for the old established wine regions with those of newer entrants. Thus, we investigate whether experience plus first choice of location matters more than the follower's advantage of newer technology. In all regions, a greater share of permanent labor and increased supervision raised efficiency, while more inorganic fertilizer and less irrigation has the opposite effect. Innovations in trellising had insignificant effects (except in the old regions) but not replacing old vines reduced efficiency. However, a higher proportion of red varietals also lowered efficiency in the old regions due to a fall in the price of red wine as these farmers continued to concentrate on quality reds. The new regions compensated for falling prices by increasing crop size with irrigation and fertilizer and extending the area planted, but with less concern for quality. This appears to be more successful in efficiency terms, but as international demand for quality wine increases it may be a poor long‐term strategy.  相似文献   
994.
We study the dynamics of smallholder participation in export value chains focusing on the example of small‐scale broccoli producers in the highlands of Ecuador. Combining cross‐sectional data from a household survey with 11‐year longitudinal data on export market transactions, we explain the hazards of dropping out of a high‐value export chain. We apply a multispell cox duration model that allows us to consider multiple entries and exits from the supply chain. We also provide evidence on the welfare impacts associated with participation. The results suggest that small‐scale farmers’ exit from the export sector is accelerated by high transaction risks experienced in the past. While we find no particular evidence for the exclusion of small‐scale farmers from the export sector, we do find that poorer households and female‐headed households tend to drop out faster, especially as long as the sector is still prospering. Finally, when considering welfare effects, we do not find evidence that participation translates into tangible benefits for broccoli farmers. We discuss some measures that could help improve the long‐term sustainability of smallholder integration in high‐value chains.  相似文献   
995.
Malnourishment continues to remain a challenge in developing countries. As the undernourished are largely smallholder farmers, it is widely assumed that farm diversification and mixed crop‐livestock agricultural systems can help alleviate this problem. However, empirical evidence in this context is limited. Hence, we use a two‐year panel's data from Laos to examine whether farm production diversity as well as a mixed crop‐livestock farming system improves household dietary diversity among smallholder farmer. The results from the fixed effects regression indicate that although farm production diversity does lead to a higher dietary diversity, the effect diminishes with continued farm diversification. The counterfactual analysis from the endogenous switching regression reveals that mixed crop‐livestock farming systems do not necessarily enhance dietary diversity. However, we further find that purchasing food from the markets plays an important role in enhancing the dietary diversity of rural smallholder farmers.  相似文献   
996.
Modern agricultural supply chains have been playing an increasingly important role in developing countries and have had significant effects on rural labor markets. This article analyses the effects of smallholder farmer participation in export vegetable supply chains in Northern Tanzania on both household hired labor demand and off‐farm labor supply, using an age‐disaggregated approach. In our sample, neither separability nor exogeneity of smallholder farmer participation in export supply chains can be rejected. Hence, we apply lognormal double‐hurdle models and find that participation in export supply chains positively affects households’ decision to hire labor from all age groups. We also find that it increases the unconditional overall level of hired labor demand, while the age‐disaggregated analysis shows that these effects mostly benefit rural youth. However, our sample does not allow us to establish statistically significant evidence of an effect on household off‐farm labor supply although the point estimates point to nonnegligible positive effect sizes.  相似文献   
997.
We analyze the role of farm stock management on price volatility under liquidity constraints and heterogeneous price expectations. In commodity markets, speculative behaviors by stockholders tend to reduce price volatility, but this is not the case in certain agricultural markets, where speculation by farmers regarding decisions to sell or store grain is subject to liquidity constraints and heterogeneous price expectations. Like stockholders, most farmers sell grain if they expect a price drop in the near future, but unlike stockholders, they are not necessarily able to purchase grain if they expect a price increase in the next period. Heterogeneous price expectations can also lead to suboptimal storage decisions, further increasing price volatility. For these reasons, the storage management behavior of farmers often fails to mitigate price drops in the way that speculation by stockholders does. We merge historical data on maize prices and household storage collected in Burkina Faso in order to build a dynamic panel over the 2005–2012 period. We show that carryover from one season to the next is associated with unexpected price drops during the preceding lean season and that carryover is associated with more frequent unexpected price drops following the subsequent post‐harvest season.  相似文献   
998.
Climate variability with unexpected droughts and floods causes serious production losses and worsens food security, especially in Sub‐Saharan Africa. This study applies stochastic bioeconomic modeling to analyze smallholder adaptation to climate and price variability in Ethiopia. It uses the agent‐based simulation package Mathematical Programming‐based Multi‐Agent Systems (MPMAS) to capture nonseparable production and consumption decisions at household level, considering livestock and eucalyptus sales for consumption smoothing, as well as farmer responses to policy interventions. We find the promotion of new maize and wheat varieties to be an effective adaptation option, on average, especially when accompanied by policy interventions such as credit and fertilizer subsidy. We also find that the effectiveness of available adaptation options is quite different across the heterogeneous smallholder population in Ethiopia. This implies that policy assessments based on average farm households may mislead policy makers to adhere to interventions that are beneficial on average albeit ineffective in addressing the particular needs of poor and food insecure farmers.  相似文献   
999.
There is a lack of evidence for impact at scale of vegetable research and development, although the importance of vegetables for human nutrition and smallholder incomes is generally understood. We therefore study adoption and impact of improved tomato and African eggplant varieties developed through international agricultural research, released by national agricultural research and extension systems, and supplied to farmers by private seed companies in East and Southern Africa from 1990 to 2014. The study finds that in 2014, varieties developed by the World Vegetable Center accounted for 50% of tomato and 98% of African eggplant commercial seed production in East and Southern Africa. For Tanzania alone, investment in crop improvement generated economic gains of US$ 255 million for tomato and US$ 5 million for African eggplant up to 2014. The internal rate of return is 26% for tomato and 12% for African eggplant, though we project the latter to increase to 26% by 2024 as the variety was released only in 2007. These findings support the view that agricultural policy and investment reoriented towards contemporary nutritional challenges will give high returns to investment.  相似文献   
1000.
This study establishes the cocoa pricing subsidization options that will stabilize processors’ throughput while meeting the multiple, but possibly conflicting, public policy objectives of maximizing government revenue and reducing poverty among Ghanaian cocoa beans producers. To evaluate these options, we construct and numerically simulate a structural dynamic stochastic model of a representative cocoa processor who maximizes the present value of current and expected future profits, given prevailing market conditions and cocoa pricing policies. Our results indicate that, given current processing capacity, the Ghana Cocoa Board would have to offer a 92% discount to processors on main‐crop beans in order to achieve the industrial goal of locally processing 40% of annual production. This would cause light‐crop beans used in processing to be completely displaced by main‐crop beans carried over as inventory. It would also increase mean processor revenues by 167%, but cause the Ghana Cocoa Board to operate at a significant deficit, implying that the stated goal could only be achieved through massive government subsidies.  相似文献   
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