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91.
Welfare gains to long-horizon investors may derive from time diversification that exploits nonzero intertemporal return correlations associated with predictable returns. Real estate may thus become more desirable if its returns are negatively serially correlated. While it could be important for long-horizon investors, time diversification has been mostly investigated in asset menus without real estate and focusing on in-sample experiments. This article evaluates, ex post, the out-of-sample gains from diversification when equity real estate investment trusts (REITs) belong to the investment opportunity set. We find that diversification into REITs increases both the Sharpe ratio and the certainty equivalent of wealth for all investment horizons and for both classical and Bayesian (who account for parameter uncertainty) investors. The increases in Sharpe ratios are often statistically significant. However, the out-of-sample average Sharpe ratio and realized expected utility of long-horizon portfolios are frequently lower than that of a one-period portfolio, which casts doubt on the value of time diversification.  相似文献   
92.
We analyse the pricing and informational efficiency of the Italian market for options written on the most important stock index, the MIB30. We report that a striking percentage of the data consists of option prices violating basic no‐arbitrage conditions. This percentage declines when we relax the no‐arbitrage restrictions to accommodate the presence of bid/ask spreads and other frictions but never becomes negligible. We also investigate the informational efficiency of the MIBO and conclude that option prices are poor predictors of the volatility of MIB30 returns. This conclusion is robust to a number of statistical and sampling methods.
(J.E.L.: G13, G14).  相似文献   
93.
ABSTRACT ** : This paper explores the application of several panel data models in measuring productive efficiency of the electricity distribution sector. Stochastic Frontier Analysis has been used to estimate the cost‐efficiency of 59 distribution utilities operating over a nine‐year period in Switzerland. The estimated coefficients and inefficiency scores are compared across three different panel data models. The results indicate that individual efficiency estimates are sensitive to the econometric specification of unobserved firm‐specific heterogeneity. This paper shows that alternative panel models such as the ‘true’ random effects model proposed by Greene (2005) could be used to explore the possible impacts of unobserved firm‐specific factors on efficiency estimates. When these factors are specified as a separate stochastic term, the efficiency estimates are substantially higher suggesting that conventional models could confound efficiency differences with other unobserved variations among companies. On the other hand, refined specification of unobserved heterogeneity might lead to an underestimation of inefficiencies by mistaking potential persistent inefficiencies as external factors. Given that specification of inefficiency and heterogeneity relies on non‐testable assumptions, there is no conclusive evidence in favour of one or the other specification. However, this paper argues that alternative panel data models along with conventional estimators can be used to obtain approximate lower and upper bounds for companies' efficiency scores.  相似文献   
94.
Massimo Introvigne 《Futures》2004,36(9):979-990
The category of “new religions” is somewhat controversial, but fringe minorities remain an interesting starting point in order to assess the future of religion. Contrary to what many expected in the 1970s, interest in religion in general has not declined in the Western world, organized religion has not disappeared, and we have not witnessed an explosion of “cults”. Learning from these past sociological prophecies that failed, we may speculate on the future in more realistic terms. New religious movements will not disappear, but they will not meet with an exceptional success either, this paper predicts, because models marginalizing them as based on brainwashing or being a form of religious kitsch, although criticized within the academic community, serve a basic psycho-cultural need of explaining away unpopular choices of our fellow human beings, and will probably not disappear from popular and media prejudice.  相似文献   
95.
Summary. In a multiple priors model á la Gilboa and Schmeidler (1989), we provide necessary and sufficient behavioral conditions ensuring the countable additivity and non-atomicity of all priors.Received: 25 November 2002, Revised: 24 June 2004, JEL Classification Numbers: D81.We thank Roko Aliprantis, Maristella Botticini, Erio Castagnoli, Larry Epstein, Paolo Ghirardato, Itzhak Gilboa, Luigi Montrucchio, David Schmeidler, Marciano Siniscalchi, an Associate Editor, and an anonymous referee for helpful discussions. Fabio Maccheroni and Massimo Marinacci gratefully acknowledge the financial support of MIUR and NOMOS Sistema (Milano).  相似文献   
96.
In manufacturing industries, occupational health and safety measures ensure better working conditions for employees, which may influence their productivity. We study the impact of investments undertaken by small and medium enterprises in Vietnam in mitigating indoor pollution (including air quality improvements, heat and noise protection as well as lighting) on firm-level gross output and value added. We find that the amount invested by the firm in health has a significant positive effect on both outcomes. Given historically poor working conditions in Vietnam, policy implications relate to incentivizing and enabling firms to undertake such investments, on both moral and economic grounds.  相似文献   
97.
Using a new European Commission‐sponsored longitudinal dataset—the VICO dataset—we assess the impact of independent (IVC) and corporate venture capital (CVC) investments on the economic performance of European high‐tech entrepreneurial firms during the period 1992–2010. After controlling for potential sources of endogeneity and selection bias, our results indicate that both IVC and CVC investments boost portfolio firms' economic performance. These effects are mostly due to an increase in real sales value. Moreover, the dynamics of the impact of VC investments on firms’ overall economic performance and its components—real sales value, real fixed assets, and real labor costs—differs depending on the type of investor. Finally, we do not detect any impact related to the syndication of investments by both IVC and CVC investors.  相似文献   
98.
We present a new type of Artificial Neural Networks: the Self-Reflexive Networks. We utter the theoretical presuppositions; their dynamics is analogous to the one ascribed to autopoietic systems: self-referentiality, unsupervised learning and unintentionally cooperative and contractual activities of their own units. We also hypothesize a new concept of perception. We present the basic equations of Self-Reflexive Networks, new concepts as the one of dynamic target, of Re-entry with dedicated and fixed connections, of Meta-Units. Therefore, we experiment a specific type of Self-Reflexive Networks, the Monodedicated, within the interpretation of a toy-DB and we have hinted at other already made experimentations, experimentations in process and planned experimentations. From the applicative work that we present a few specifics and novelties of this type of Neural Networks emerge:
  1. the capability of answering to complex, strange, wrong or not precise questions, through the same algorithms through which the learning phase took place.
  2. the capability of spontaneously transforming their own learning inaccuracy in analogic capability and original self-organization capability.
  3. the capability of spontaneously integrate the models that it experienced in different moments in an achronical hyper-model.
  4. the capability of behaving as it had explored a decisions graph of large dimensions, both deeply and in extension. With the consequence of behaving as an Addressing Memory forself-dynamic Contents.
  5. the capability of always learning, rapidly and anyway, besides the complexity of the learning patterns.
  6. the capability of answering simultaneously from different points of view, behaving, in this case, as a network that builds more similarity models for each vector-stimulus that it receives.
  7. the capability of adjusting in a biunivocal way, each question to the consulting DB and each DB to the question that are submitted. The consequence of this fact is the continuous creation of new answering models.
  8. the capability of building during the learning phase, a weights matrix that provides a subconceptual representation of the bi-directional relations between each couple of input variables.
  9. the capability, through the Metaunits, to integrate in a unitary typology, nodes with different saturation speed and, therefore, with different memory: in fact, while the SR units are short memory nodes, since each new stumulus zeros the previous stimulus, the Metaunits memorize the SR different stimulus during time, functioning as an average length memory. This fact should confirm that the avarage length memory is of a different level from the immediate memory and that it is based only uponrelation among perceptive stimulus which are distributed in parallel and in sequence. In this context the weights matrix constitute the SR long term memory. And in this sense it will be opportune to think at a methodic through which the Metaunits can influence during time, the same weights matrix. In any case, in the SR there areservice nodes orfilter nodes andlearning nodes as if they were weights (the Metaunits).
  相似文献   
99.
In this paper we focus on the determinants of internationalization and, in particular, on the specific role played by the agglomeration of small and medium sized enterprises (SMEs) through their proximity to a large firm. We study the characteristics of the internationalization process in a representative sample of 786 firms in the Italian automotive supply chain. After building an Internationalization Strategy Index (ISI), we perform a multinomial logit econometric analysis. The main findings of the empirical analysis are: (a) Italian automotive supplier firms mainly go in the foreign markets through export, i.e. the simplest internationalization mode; (b) as predicted in the literature, individual firm characteristics play a significant role in the probability of internationalization; (c) firms located in the province of Turin, where the dominant car assembler (Fiat) in Italy has its headquarters, or more generally, in large automotive industry districts, enjoy a clear localization advantage; (d) interestingly, we also find that internationalization is negatively correlated with the share of Fiat in suppliers’ sales, and that suppliers located in a district and less dependent on Fiat are also those adopting the most advanced internationalization strategies.  相似文献   
100.
ABSTRACT: We analyze economies of scale and scope in Swiss Post's post offices and franchised postal agencies under consideration of different underlying production technologies and unobserved factors using a latent class model. The results confirm the existence of unobserved heterogeneity and of increasing economies of scale and scope in the Swiss Post's outlet network.  相似文献   
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