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891.
Risk perception is often measured by a direct method, e.g., a questionnaire. This mainly reveals the deliberate evaluation of a risk (a so‐called secondary evaluative process), whereas risk perception can also be based on a first, spontaneous reaction (a primary evaluative process). An indirect test such as the Extrinsic Affective Simon Task (EAST, De Houwer, 2003 De Houwer, J. 2003. The Extrinsic Affective Simon Task. Experimental Psychology, 50: 7785. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]) may be needed to reveal this first, spontaneous reaction. In this study, a questionnaire and an EAST measured the effects of varying risk communications (high risk, low risk or control article), about high‐voltage power lines. The results of the EAST showed that the respondents associated power lines stronger with unhealthy than with healthy. However, the questionnaire results did not seem to indicate that the respondents considered power lines as risky. The EAST did not reveal an effect of article variation on the associations of power lines with (un)healthy. Conversely, the questionnaire results showed that article variation influenced the secondary evaluative process. Further, our findings demonstrated that the direct and indirect measures were unrelated. An indirect test may complement a direct test to get an overall picture of how people evaluate risks.  相似文献   
892.
This article draws from the experience of the ongoing drafting of the Regional Plan of the Centre Region of Portugal, and the empirical application of the Social Vulnerability Index proposed by Susan Cutter. It consists in the construction of an index of social vulnerability to natural and technological hazards and to social risks for all the municipalities of the region. Methodologically, it extends the vulnerability analysis to technological hazards and social risks, as a more encompassing view is necessary for the elaboration of prevention and civil protection policies. The results confirm the interactive nature of social vulnerability, and they also reflect the diffuse urbanisation and industrialisation patterns that characterise Portugal. The scattered nature of social facilities and security and health infrastructures pose specific challenges to planners concerning risk prevention and mitigation, and the elaboration of effective risk communication strategies adapted to specific hazards and risks in the studied municipalities. The article concludes with some reflections on the need to revise established paradigms of disaster analysis and emphasise the importance of pre‐event planning and the social cartography of vulnerable populations for effective prevention and security policies that take into account social inequalities and citizenship rights.  相似文献   
893.
The present study analyzes the influence that perceived risk in online shopping has on the process of e‐commerce adoption by end consumers. With this aim, the Technology Acceptance Model is taken as a reference framework, proposing an Extended E‐Commerce Acceptance Model that includes the diverse constructs of perceived risk: financial, performance, social, time, psychological and privacy. Empirical evidence is obtained from two samples, one is composed by Internet users with no experience in web shopping and the other is formed by online buyers. The results obtained confirm that the intention to shop through the Internet is positively influenced by general attitude toward the system and negatively influenced by the risk associated with the Web. Regarding the importance of the risk dimensions considered in the study, the economic and performance facets are the ones that have a greater influence on e‐commerce adoption, while social and time dimensions are the less relevant.  相似文献   
894.
This study seeks to inform investment academics and practitioners by describing and analyzing the population of return predictive signals (RPS) publicly identified over the 40-year period 1970–2010. Our supraview brings to light new facts about RPS, including that more than 330 signals have been reported; the properties of newly discovered RPS are stable over time; and RPS with higher mean returns have larger standard deviations of returns and also higher Sharpe ratios. Using a sample of 39 readily programmed RPS, we estimate that the average cross-correlation of RPS returns is close to zero and that the average correlation between RPS returns and the market is reliably negative. Abstracting from implementation costs, this implies that portfolios of RPS either on their own or in combination with the market will tend to have quite high Sharpe ratios. For academics who seek to document that they have found a genuinely new RPS, we show that the probability that a randomly chosen RPS has a positive alpha after being orthogonalized against five (25) other randomly chosen RPS is 62 % (32 %), suggesting that the returns of a potentially new RPS need to be orthogonalized against the returns of some but not all pre-existing RPS. Finally, we posit that our findings pose a challenge to investment academics in that they imply that either US stock markets are pervasively inefficient, or there exist a much larger number of rationally priced sources of risk in equity returns than previously thought.  相似文献   
895.
Knowledge gleaned from previous acquisitions may confer valuation expertise and other benefits. But numerous acquisitions also entail costs, due to problems of incorporating diverse units into an ever larger firm. Such benefits and costs are not directly observable from outside the firm. This article proposes a simple model to infer their relative importance, using the time between successive deals. The data requirements are minimal and allow the use of all mergers and acquisitions during 1992–2009 (more than 300,000 deals). The results provide evidence of learning gains through repetitive acquisitions, especially under CEO continuity and when successive deals are more similar.  相似文献   
896.
The two-stage competition is investigated in which two Internet Service Providers (ISP) choose sequentially their capacities and then their prices while facing a flow of new customers who decide to belong to one ISP or the other on the basis of a comparison of access prices and of expected congestion rates. At the equilibrium of the game a vertical differentiation between the Internet Service Providers endogenously emerges: the firm which provides the larger network has the lowest rate of congestion and the highest access price. The ISP providing the smallest network (thus the most congested) earns the larger profit. It will be noticed that the spontaneous functioning of oligopolistic competition produces a result similar to the Odlyzko's ‘Paris Metro Pricing’: at the equilibrium the two competitors propose different prices and rates of congestion, the most expensive one being also the least congested.  相似文献   
897.
The introduction of the flex-fuel cars in the Brazilian market in 2003 changed considerably the consumer decision-making process. Prior to this date, it was necessary to choose the automobile type only by gasoline or by ethanol fuel; today it is possible to choose a car type with both fuel options. This flexibility generates economic advantages for his owner, but what are the financial benefits of a flex-fuel car in comparison with a car using only gasoline? Geographically, where is the owner of the benefits from this flexibility located? This article presents an empirical application of the Real Options Theory in the analysis of the flex-fuel car option for five geographic Brazilian regions: Northern, Northeastern, Central-Western, Southeastern and Southern. The regional price differences as well as the consumer preferences of these regions were met. For this purpose, historical fuel prices were considered stochastic and following a Mean Reverting Stochastic process. The prediction and option values were generated by a Monte Carlo simulation. The results indicated that the option embedded on the Brazilian flex-fuel car adds considerable value to the owner in all regions and car models considered, with the Southeastern Region receiving most benefits by the flex option.  相似文献   
898.
This article investigates the pair-wise convergence hypothesis of 17 Spanish regions with respect to the European Union (EU) and Euro-Zone (EZ). Several definitions of convergence are taken into account. The IB-MPI unit root testing procedure is then applied. A simultaneous approach based on the gap in levels and logs is developed to study convergence. The empirical results show incomplete catching-up in six cases with respect to both EU and EZ, and complete catching-up in nine with respect to EU and four with respect to EZ. When taking into account the behaviour of both gaps and loggaps, we further get four cases of cointegrated regions with respect to EZ and only one with respect to EU. Finally, there are four regions that diverge with respect to EU, but do converge with respect to the EZ. Only Baleares diverges with respect to both of them.  相似文献   
899.
ABSTRACT

Platform competition shapes and is shaped by a constantly changing socioeconomic context. Three trends provide evidence for this: (i) the number of firm level relevant factors for platform success is steadily increasing, (ii) contemporary cases of platform competition take less time to unfold, and (iii) industries converge. These trends suggest that there is a change: in the time required for relevant factors to influence platform competition, and in the trade-offs managers face when they take actions in platform development and competition, to influence the market outcome of such processes. Current frameworks in the literature do not account explicitly for such timing issues. The use of modelling and simulation, along empirical cases, is a way to incorporate timing and strategic action delays in platform competition research. We explore the multi-level research agenda this opens up and develop nine research questions for platform competition research.  相似文献   
900.
ABSTRACT

This paper analyzes the relationship between withdrawals from Brazilian open retirement funds, portfolio composition (fixed income or equity) and frequency of statement sending (monthly, quarterly, semiannually or annually). Our results indicate that equity retirement plans present a lower withdrawal index when compared to that of fixed income plans. Furthermore, the higher the statement sending frequency, the lower the withdrawals from open retirement plans. However, withdrawals from equity retirement plans tend to increase when statements are sent to investors more frequently. These phenomena can be explained by behaviorist theories, such as the concept of myopic loss aversion. In a context where loss aversion is present, the more frequently the investor evaluates his or her portfolio, or the shorter the investment horizon, the less attractive he or she will find investment in assets with a high rate of return and risk, such as equities. This behavior occurs not only regarding short-term investments, but also traditional long-term assets such as equity retirement plans.

RESUMEN. Este estudio analiza la relación existente entre las retiradas de los fondos abiertos de jubilación brasileños, la composición de la cartera (ingreso fijo o patrimonio), y la frecuencia del envío de estados financieros (mensual, trimestral, semestral o anualmente). Nuestros resultados indican que los planes de jubilación patrimonial tienen un índice de retirada menor, en comparación con los planes de ingreso fijo. Además, cuanto mayor la frecuencia de los estados financieros, menor es la retirada de los planes abiertos de jubilación. Sin embargo, las retiradas de los planes de jubilación patrimoniales tienden a aumentar cuando los estados se envían a los inversores con más frecuencia. Este fenómeno puede explicarse con las teorías comportamentales, tales como el concepto de la aversión miope a la pérdida. En un contexto donde la aversión a la pérdida es una realidad, cuanto mayor la frecuencia con que el inversor pueda evaluar su carera, o menor el horizonte de inversión, menos atractivas considerará él las inversiones en activos con un alto retorno y riesgo, tal como las acciones. Este comportamiento ocurre no sólo en las inversiones a corto plazo, sino también en los activos a largo plazo, como los planes de jubilación patrimoniales.

RESUMO. Este artigo analisa a relação entre as retiradas dos fundos abertos de aposentadoria brasileiros, a composição da carteira (renda fixa ou ações) e a freqüência da remessa de extratos (mensal, trimestral ou semestral). Nossos resultados indicam que os planos de aposentadoria que aplicam em ações apresentam um índice de retirada menor em comparação com os planos de renda fixa. Além disso, quanto maior a freqüência de remessa de extratos, menores as retiradas dos planos abertos de aposentadoria. Entretanto, as retiradas dos planos de aposentadoria que aplicam em ações tendem a aumentar quando o extrato é enviado aos investidores commais freqüência. Esses fenômenos podem ser explicados por teorias behavioristas, como o conceito de aversão míope à perda. Num contexto onde a aversão à perda esteja presente, quanto maior a freqüência com que o investidor avalia a sua carteira, ou quanto menor o horizonte do investimento, menos atraente ele achará o investimento em ativos com alto retorno e risco, como ações. Esse comportamento ocorre não apenas em investimentos a curto prazo, mas também nos ativos tradicionais de longo prazo como os planos de aposentadoria com aplicação em ações.  相似文献   
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