全文获取类型
收费全文 | 29031篇 |
免费 | 663篇 |
专业分类
财政金融 | 5264篇 |
工业经济 | 2140篇 |
计划管理 | 4934篇 |
经济学 | 6583篇 |
综合类 | 308篇 |
运输经济 | 180篇 |
旅游经济 | 479篇 |
贸易经济 | 4457篇 |
农业经济 | 1407篇 |
经济概况 | 3871篇 |
邮电经济 | 71篇 |
出版年
2021年 | 167篇 |
2020年 | 276篇 |
2019年 | 372篇 |
2018年 | 539篇 |
2017年 | 531篇 |
2016年 | 501篇 |
2015年 | 375篇 |
2014年 | 573篇 |
2013年 | 2789篇 |
2012年 | 778篇 |
2011年 | 846篇 |
2010年 | 672篇 |
2009年 | 804篇 |
2008年 | 847篇 |
2007年 | 759篇 |
2006年 | 705篇 |
2005年 | 658篇 |
2004年 | 657篇 |
2003年 | 644篇 |
2002年 | 595篇 |
2001年 | 603篇 |
2000年 | 599篇 |
1999年 | 518篇 |
1998年 | 525篇 |
1997年 | 501篇 |
1996年 | 501篇 |
1995年 | 451篇 |
1994年 | 497篇 |
1993年 | 506篇 |
1992年 | 471篇 |
1991年 | 498篇 |
1990年 | 454篇 |
1989年 | 378篇 |
1988年 | 388篇 |
1987年 | 381篇 |
1986年 | 395篇 |
1985年 | 569篇 |
1984年 | 530篇 |
1983年 | 533篇 |
1982年 | 515篇 |
1981年 | 443篇 |
1980年 | 435篇 |
1979年 | 448篇 |
1978年 | 380篇 |
1977年 | 343篇 |
1976年 | 273篇 |
1975年 | 266篇 |
1974年 | 248篇 |
1973年 | 238篇 |
1972年 | 196篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
191.
Portfolio value‐at‐risk (PVAR) is widely used in practice, but recent criticisms have focused on risks arising from biased PVAR estimates due to model specification errors and other problems. The PVAR estimation method proposed in this article combines generalized Pareto distribution tails with the empirical density function to model the marginal distributions for each asset in the portfolio, and a copula model is used to form a joint distribution from the fitted marginals. The copula–mixed distribution (CMX) approach converges in probability to the true marginal return distribution but is based on weaker assumptions that may be appropriate for the returns data found in practice. CMX is used to estimate the joint distribution of log returns for the Taiwan Stock Exchange (TSE) index and the associated futures contracts on SGX and TAIFEX. The PVAR estimates for various hedge portfolios are computed from the fitted CMX model, and backtesting diagnostics indicate that CMX outperforms the alternative PVAR estimators. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26:997–1018, 2006 相似文献
192.
This study was undertaken to investigate the inclusion of a kosher claim in an advertisement for a familiar and unfamiliar
brand of breakfast cereal. Results showed that, as hypothesized, for the familiar brand a kosher third party endorsement led
to significantly more kosher attribute-related thoughts, more favorable product attitude and greater purchase intention. For
the unfamiliar brand, no significant impact upon these dependent measures was observed given a kosher endorsement. Findings
are interpreted from a cognitive perspective regarding the salience of the kosher attribute in a product familiarity context.
Managerial implications are discussed. 相似文献
193.
194.
Paul J. Haensly Thomas M. Springer Neil G. Waller 《The Journal of Real Estate Finance and Economics》1993,6(2):157-166
In this research we use a continuous payment formula for duration to examine the price behavior of a fixed-rate level payment mortgage. In the case where the mortgage is held to maturity, duration increases monotonically as term-to-maturity increases, regardless of changes in the market rate of interest. In the case where the mortgage is prepaid prior to maturity, there exists a unique market interest rate below which duration is a monotonically increasing function of time of prepayment, but above which duration has a global maximum at some time of prepayment prior to the term-to-maturity. 相似文献
195.
Abstract
Technology analysis is a new technomanagerial discipline that provides common frameworks for analysing individual technologies and their relationships to each other. It is used here to probe the development of a particular technology, namely that of permanent magnets.
The paper traces the development of permanent magnets over the past decade and explores possible future improvements in performance parameters. The strength of magnets (i.e. energy product as expressed in kilo Joules per cubic metre) has increased from approximately 40 in the 1930s to approximately 400 at present.
Future developments will be constrained by a barrier which seems to exist at approximately 525 kilo Joules per cubic metre. However this is viewed as a barrier that can be transcended and not as an immutable limit. It therefore signifies a possible breakthrough zone.
S-curve theory leads analysts to speculate about a possible breakthrough during the five year period leading up to 1995. At that date magnetic strengths of 600+ kilo Joules per cubic metre could be aimed for.
Increased magnetic strength will improve the performance parameters of all technologies utilising magnets, unleash new magnetic based technologies and threaten many traditional areas in the fields of matter processing, transporting and storing, energy processing, and information processing and storing.
These effects will cascade through the entire technological landscape creating new markets and destroying others. The article gives an overview of these impacts on the technological landscape. 相似文献
Technology analysis is a new technomanagerial discipline that provides common frameworks for analysing individual technologies and their relationships to each other. It is used here to probe the development of a particular technology, namely that of permanent magnets.
The paper traces the development of permanent magnets over the past decade and explores possible future improvements in performance parameters. The strength of magnets (i.e. energy product as expressed in kilo Joules per cubic metre) has increased from approximately 40 in the 1930s to approximately 400 at present.
Future developments will be constrained by a barrier which seems to exist at approximately 525 kilo Joules per cubic metre. However this is viewed as a barrier that can be transcended and not as an immutable limit. It therefore signifies a possible breakthrough zone.
S-curve theory leads analysts to speculate about a possible breakthrough during the five year period leading up to 1995. At that date magnetic strengths of 600+ kilo Joules per cubic metre could be aimed for.
Increased magnetic strength will improve the performance parameters of all technologies utilising magnets, unleash new magnetic based technologies and threaten many traditional areas in the fields of matter processing, transporting and storing, energy processing, and information processing and storing.
These effects will cascade through the entire technological landscape creating new markets and destroying others. The article gives an overview of these impacts on the technological landscape. 相似文献
196.
197.
This paper examines the impact of announcements of dividend changes by bank holding companies (BHCs) on equity returns. Many empirical studies of dividend behavior reveal positive market responses to dividend increases, which have been interpreted as confirmation of the signalling theory of dividend behavior. These studies typically focus on “large” changes, however. We argue that BHCs allow for a stronger test of signalling theory because regulatory monitors, in effect, “certify” dividend signals. Consequently, even “small” dividend increases should result in positive abnormal equity returns. Using the event study methodology, our results generally confirm this hypothesis for a sample covering the period 1973–1987. 相似文献
198.
This paper models the demand for stockbrokers' services in Australia, consisting of two related services, agency trades and principal trades. The relationship between agency and principal trades is estimated. The results indicate that the two services are complements rather than substitutes. Using unique accounting information, a model of agency and principal trading activities is estimated to determine the welfare effects of (i) deregulating brokerage commissions and (ii) a ban on principal trading by brokers. The results show a sizeable welfare gain to investors (amounting to about 60% of the gross revenue of brokers) stemming from deregulation of the minimum charge for agency trades. The loss in profitability by brokers due to deregulation is also computed and shown to be negligible. The results also show that due to complementarity, a ban on principal trading, even with deregulation of agency trading, can impose an arbitrarily high cost on investors which could, in principle, offset the gains from agency deregulation. 相似文献
199.
Single or double bounded contingent valuation? A Bayesian test 总被引:2,自引:0,他引:2
This paper evaluates the performance of asymptotic approximations of the Bayes factor to appraise the relative likelihoods of the bivariate and the restricted double bounded models for contingent valuation. The performance of the Bayes factor test is studied by Monte Carlo simulation showing that it correctly chooses the bivariate model when appropriate, but tends to over predict the double bounded model when the correlation coefficient is not estimated accurately. However, the quadratic error in estimating willingness to pay is reduced if the model preferred by the test is chosen. In addition, we consider the effect of averaging the estimates of WTP from both models, weighting each model with its posterior probability. The results show that ‘model averaging’ across the competing hypothesis further reduces the squared error. The applications with two data sets on National Parks show that the test rejects the restricted double bounded hypotheses against the bivariate model. 相似文献
200.
J. Galtung 《Futures》2003,35(2):107-121
Comparing the global situation in the year 2000 with what the respondent samples from 10 countries predicted 30 years earlier, the conclusion can only be that people were remarkably accurate. This does not mean that any single respondent was that accurate but that anybody, who would have liked to anticipate the year 2000, would have done quite well based on these samples. Actually, the peripheries in the samples came out even better than the centers, making us wonder what education and high special position are actually about. One possible set of explanations would be that the peripheries know better where the shoes pinch, are more holistic and are not paid by anybody to make self-fulfilling or self-denying predictions.We are going to look at what people thought and what actually happened, in three movements. The first is about what they thought about the futures of their own societies and the second about international futures. The third movement deals with how their hopes and expectations depended on who they were, more specifically: whether they belonged to the center or the periphery in their countries. 相似文献