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921.
Artificial Intelligence (AI) and its potential impact on the demand for human labour has become a fashionable topic — particularly among economic policy advisors. However, most papers that warn about high substitution rates of conventional jobs use questionable data and methodologies. Future economic policy advice ought to include a company perspective — and discover that disruption will be much more gradual and less dramatic than proclaimed by the current topical papers. As this AI revolution is just at its very beginning, economic policy makers are advised to accompany and support digital change instead of actively intervening in digital value chains with taxes and/or subsidies. 相似文献
922.
923.
Effects of Farm Size on Technical Efficiency in China's Broiler Sector: A Stochastic Meta‐Frontier Approach 下载免费PDF全文
Xiangfei Xin Yi Zhang Jimin Wang John Alexander Nuetah 《Revue canadienne d'agroeconomie》2016,64(3):493-516
This paper employs the stochastic meta‐frontier approach to measure technical efficiency and to investigate the effects of farm size on the technical efficiency in China's broiler sector. Empirical results show a positive association between farm size and technical efficiency in China's broiler sector. The medium and large farm sizes exhibit increases of 0.058 and 0.160, respectively, in technical efficiency scores, relative to small farms, which have a mean technical efficiency score of 0.722. Results indicate that there are significant differences in technical efficiency across regions. Technical efficiency in the southern region, which is dominated by yellow‐feathered broilers, is significantly lower than that in the northern region where white‐feathered broilers are the dominant species. Also, the technical efficiency scores estimated from the meta‐frontier model vary substantially across farm sizes in the southern region. Increased farm size improves the technical efficiency for yellow‐feathered broiler production. Dans la présente étude, nous avons utilisé l'analyse métafrontière stochastique pour mesurer l'efficience technique et pour déterminer les effets de la taille de la ferme sur l'efficience technique du secteur du poulet à griller en Chine. Les résultats empiriques indiquent qu'il existe un lien positif entre la taille de la ferme et l'efficience technique. Les fermes de moyenne et grande taille affichent une augmentation du pointage d'efficience technique de 0,058 et de 0,160 respectivement, comparativement aux fermes de petite taille dont le pointage d'efficience technique moyen est de 0,722. Les résultats indiquent que l'efficience technique varie considérablement d'une région à l'autre. L'efficience technique dans la région du Sud, où l’élevage du poulet à griller blanc domine, est significativement plus faible que celle de la région du Nord, où l’élevage du poulet à griller jaune domine. De plus, les pointages d'efficience technique estimés à partir du modèle de métafrontière varient considérablement dans la région du Sud. L'augmentation de la taille de la ferme améliore l'efficience technique de la production du poulet à griller jaune. 相似文献
924.
Francesca Gerini Frode Alfnes Alexander Schjøll 《Journal of Agricultural Economics》2016,67(2):471-490
To understand the market for sustainable foods, it is important to allow for heterogeneous preferences. However, most studies of consumer preferences for sustainable foods only investigate average consumer preferences. They do not take into account that some consumer segments attempt to purchase as much sustainable food as possible, others are almost indifferent to the notion of sustainable food, and still others consider sustainable food a complete hoax. The aim of this study is to explore the preferences for various types of premium eggs across three consumer segments. We conduct a choice experiment including 900 Norwegian consumers and perform a behavioural segmentation based on the frequency of organic food purchase. We find that the segment purchasing the most organic food is, as expected, willing to pay a significant premium for organic eggs over eggs displaying only enhanced animal welfare. However, most consumers, who only occasionally purchase organic products, are unwilling to pay more for organic eggs than for enhanced animal welfare eggs, suggesting diminishing marginal utility for additional attributes. We find that a third consumer segment attempts to avoid organic eggs, even when they cost the same as other eggs. Our findings suggest that organic products will be unsuccessful in acquiring a larger share of the market as long as most consumers are unwilling to pay a premium for organic products with all their cost increasing sustainable attributes over products that have only a single sustainable attribute, in our case enhanced animal welfare. 相似文献
925.
An Econometric Analysis of the Main Components of M3 in the Euro Area. — The main result is that the four components of M3 in the euro area can be explained in terms of a small set of explanatory variables (nominal GDP and interest rates) for the sample period January 1990 — September 1999 both in terms of levels and as shares of M3. Moreover, overall cointegration tests broadly support the hypothesis of long-run stability of the demand for the components of M3 and for M3 itself in nominal terms. Around the start of Stage Three of Monetary Union significant substitution between the components of M3 is detected. A refinement of the empirical analysis takes into account the correlation of the unexplained movements of the individual components using the SUR technique. 相似文献
926.
Alexander A. Sunday 《Annals of Tourism Research》1978,5(2):268-273
Sunday, Alexander A., “Foreign Travel and Tourism Prices and Demand,” Annals of Tourism Research, Vol. V, No. 2, April/June 1978, pp. 268–273. Using regression analysis and panel data this study estimates the parameter effect of prices on American demand for foreign travel and tourism. Findings suggest that higher air fares generate fewer tourists but greater expenditure per tourist visit. 相似文献
927.
Personalien
Personalien 相似文献928.
The articles in academic journals can be regarded as a valid indicator when it comes to the definition of the status quo of a discipline, especially if the discipline experiences a period of transition, as Communication Science does. This study builds upon earlier work (Brosius 1994; 1998; Donsbach et al. 2005) in order to outline the discipline’s evolution throughout the last 25 years. Using content analysis of the two most important German journals Rundfunk und Fernsehen respectively Medien &; Kommunikationswissenschaft and Publizistik of the years 1983 to 2007, subjects for research are the various topics and research questions, the authors’ professional backgrounds and institutional affiliations, as well as publication activities and citation behavior. Results indicate an ongoing institutionalization: more than two-thirds of the research published in these journals originates from scholars affiliated with faculties of Communication Science. There is an increasing trend of concentration on the levels of academic institutions and individual authors: only few scholars and faculties produce a large share of the contributions in the journals analyzed. The pattern of publication activities found by the authors corresponds to a rule known as “Lotka’s Law,” another indication of the discipline’s continuing institutionalization. 相似文献
929.
Are local market relationships undermining organic fruit and vegetable certification? A bivariate probit analysis 下载免费PDF全文
Ariana P. Torres Maria I. Marshall Corinne E. Alexander Michael S. Delgado 《Agricultural Economics》2017,48(2):197-205
This article investigates how an organic fruit and vegetable farmer's choice to use direct‐to‐consumer market channels impacts his/her decision to be certified organic. First, we model the decision to be certified organic as a conditionally independent decision from the farmer's chosen market channels. Second, we estimate the probability of certifying organic as an endogenously determined marketing decision to the choice of market channels, and use a bivariate probit specification to model this decision. Empirical evidence indicates that the decision to certify is endogenous to the chosen market channels. We show that farmers selling direct to consumers are less likely to certify organic. 相似文献
930.
Lyubov E. Burlakova Richard P. Barbiero Alexander Y. Karatayev Susan E. Daniel Elizabeth K. Hinchey Glenn J. Warren 《Journal of Great Lakes research》2018,44(4):600-617
We used the results of seventeen years of Great Lakes benthic monitoring conducted by the U.S. EPA's Great Lakes National Program Office to describe the spatial and temporal patterns of benthic communities, assess their status, trends, and main drivers, and to infer the potential impact of these community changes on ecosystem functioning. Benthic abundance and diversity were higher at shallow (<70?m in depth) stations with chlorophyll concentrations above 3?μg/L than at deeper sites (<1?μg/L). We infer that lake productivity, measured by chlorophyll was likely the major driver of benthic abundance and diversity across lakes. Consequently, benthic diversity and abundance were the highest in the most productive Lake Erie, followed by lakes Ontario, Michigan, Huron, and Superior. Multivariate analysis distinguished three major communities shared among lakes (littoral, sublittoral, and profundal) that differed in species composition and abundance, functional group diversity, and tolerance to organic pollution. Analysis of temporal trends revealed that the largest changes occurred in profundal communities, apparent in significant shifts in dominant taxa across all lakes except Lake Superior. In lakes Michigan, Huron, and Ontario, the former dominant Diporeia was replaced with Dreissena and Oligochaeta. Profundal species, with the exception of dreissenids, became less abundant, and their depth distribution has shifted. In contrast, density and diversity of native littoral and sublittoral communities increased. The invasion of dreissenids was among the most important drivers of changes in benthic communities. Continued monitoring is critical for tracking unprecedented changes occurring in the Great Lakes ecosystem. 相似文献