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991.
This paper extends previous analyses of the choice between internal and external R&D to consider the costs of internal R&D. The Heckman two-stage estimator is used to estimate the determinants of internal R&D unit cost (i.e. cost per product innovation) allowing for sample selection effects. Theory indicates that R&D unit cost will be influenced by scale issues and by the technological opportunities faced by the firm. Transaction costs encountered in research activities are allowed for and, in addition, consideration is given to issues of market structure which influence the choice of R&D mode without affecting the unit cost of internal or external R&D. The model is tested on data from a sample of over 500 UK manufacturing plants which have engaged in product innovation. The key determinants of R&D mode are the scale of plant and R&D input, and market structure conditions. In terms of the R&D cost equation, scale factors are again important and have a non-linear relationship with R&D unit cost. Specificities in physical and human capital also affect unit cost, but have no clear impact on the choice of R&D mode. There is no evidence of technological opportunity affecting either R&D cost or the internal/external decision.  相似文献   
992.
In recent years it has been argued, from many perspectives, that the further into the future a value flow occurs, the lower is the appropriate discount rate for it. National governments are now beginning to authorise such declining discount rates. This viewpoint can be, and has been, formalised in various ways, and has been applied to evaluating forestry investments of given durations. When the optimal duration of investment is itself the issue, new problems arise. Lower discount rates make subsequent rotations longer than earlier ones, and for a given length more valuable than they would otherwise be. This affects the optimal length of earlier rotations, which in turn may affect the discount rate profile applicable to later ones. In the absence of analytical solutions for the optimal sequence of rotations, numerical protocols are needed. The results arising are mostly in accord with expectations. If the change of discount rate is due to expected changes of circumstance that are actually realised, then the optimal sequence of rotations will remain as initially determined. If, however, it is due merely to the particular time perspective of the present generation, rotations will be revised by future generations. This will lead to a sequence of rotations similar to that deemed optimal at the current short-term discount rate. The most important reductions in profitability caused by choosing the “wrong” discounting protocol arise from the “wrong” rate, rather than by using declining rates as such.  相似文献   
993.
This article uses a novel experimental approach to measure consumer willingness to pay (WTP) for wine attributes. We invited customers of a local supermarket who had selected a bottle of wine to purchase to participate in a valuation experiment. Integrating their original wine choice into the experiment, each participant evaluated six alternative wines, generating a rich set of data on willingness to pay and consumer characteristics. The data from the experiment allow us to compare standard shelf price‐based wine attribute valuation estimates with estimates using WTP data and an increasing amount of information about individual consumers. The full model employs individual fixed effects to estimate WTP parameters without bias from consumer sorting or supply side influences. Our WTP estimates for wine attributes differ markedly from previous attribute value estimates. Consumers in our sample display clear and stable preferences for wine varieties, but less clear preferences for appellations. Our results suggest caution is needed in using market prices to estimate parameters of the consumer valuation function for product attributes.  相似文献   
994.
首先根据循环经济的"3R"原则和黑龙江省林业循环经济发展的实际情况,建立了林业循环经济发展水平评价指标体系;然后依据黑龙江省2001年到2011年的指标数据,运用主成分分析方法,综合分析出黑龙江省林业循环经济总体发展趋势,并从资源消耗、资源循环利用、社会和经济发展、生态环境4个方面分阶段评述了黑龙江省林业循环经济的发展水平,浅析了各阶段取得成效和存在问题的原因。  相似文献   
995.
Production risk is an inherent characteristic of agriculture and changes in production risk will affect the welfare of risk‐averse producers. Using standard concepts from the literature on uncertainty, we introduce a welfare measure which comprises total factor productivity (TFP), production risk and farmer risk preferences, and which reflects the impact on producer welfare of changes in production technology. An empirical application is carried out using data from a sample of Spanish dairy farms which shows how the positive impact of increases in TFP on welfare can be offset by increases in the risk premium (‘cost of risk’) to the point where welfare may decrease.  相似文献   
996.
We extend the Tobit (censored) linear equation system procedure to utility‐theoretic demand functions, along with a mapping mechanism to impose the adding‐up restriction implied by consumer utility maximization theory—a theoretical restriction very often ignored in previous empirical studies with censored demand systems. In this context, the Bayesian Markov Chain Monte Carlo (MCMC) procedure is applied to the censored linear approximate almost ideal demand system (LAIDS) for 12 food products, using data from the Turkish Household Expenditure Survey. All own‐price elasticities are negative and expenditure elasticities positive. Uncompensated own‐price elasticities for rural households are generally much higher than those for their urban peers, though demand for most food products are own‐price elastic for both types of households. The differential patterns in demand elasticities between urban and rural households become even more evident (almost twice) as relatively more expensive foodstuffs are consumed, showing that accessibilities to alternative products have made rural Turkish households more cognizant toward price changes in foods. Household characteristics play a key role in food expenditures, notably so in urban areas, and regional and seasonal differences are also present.  相似文献   
997.
This article analyzes the theoretical underpinnings of producer willingness to pay (WTP) for new inputs. In addition to conceptualizing the producer WTP function, we derive its comparative statics and show how these properties can be used to estimate quantities demanded or supplied and price elasticities. We also discuss implications of the comparative statics.  相似文献   
998.
999.
In recent years, France has been facing particularly severe drought periods especially in summer. In a country where agriculture is the largest water user, some irrigation management companies have implemented innovative pricing systems to handle this situation. The objective of this article is to analyze the impact of these new management systems on farmers’ incomes, the revenue of the management companies, and the amount of water used. To do that, we develop a methodology using a stochastic model that simulates the representative farmer's optimal behavior in a context of climatic variability. An empirical application is made with a crop growth model and data collected from the Midi‐Pyrenees region. The results show that using these specific nonlinear pricing systems allow irrigation water managers to reduce the impact of drought on production. Moreover, the type of pricing implemented depends on the characteristics and capabilities of the water company. More particularly, these pricing systems can be used to anticipate agricultural water demand in order to avoid imbalance with water availability.  相似文献   
1000.
美国宝洁公司在中国改革开放之际,敏锐地察觉到中国市场的巨大潜力,向中国日用品市场进驻。在多元品牌政策和差异性市场策略的总体策略指引下,宝洁公司充分考虑中国经济,政治,文化背景,以中国东西部经济差距,城乡消费者需求差异,中国消费者对传统文化的要求和可持续发展为基础,开发具有中国传统品味的高科技环保产品,建立特殊的分销体系,建立了在中国市场的首席地位。同时,宝洁公司以遵守中国法律,履行社会责任和道德准则为己任,与当地政府配合,协助开展文化和经济辅导活动,保护生态环境与自然资源,在消费者心目中建立了良好的企业形象,为进一步发展提供了有利基础,达到了双赢的目的。  相似文献   
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