全文获取类型
收费全文 | 373篇 |
免费 | 16篇 |
专业分类
财政金融 | 62篇 |
工业经济 | 15篇 |
计划管理 | 72篇 |
经济学 | 82篇 |
综合类 | 2篇 |
运输经济 | 8篇 |
旅游经济 | 6篇 |
贸易经济 | 106篇 |
农业经济 | 20篇 |
经济概况 | 16篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 4篇 |
2020年 | 7篇 |
2019年 | 7篇 |
2018年 | 13篇 |
2017年 | 23篇 |
2016年 | 16篇 |
2015年 | 7篇 |
2014年 | 17篇 |
2013年 | 58篇 |
2012年 | 17篇 |
2011年 | 15篇 |
2010年 | 28篇 |
2009年 | 20篇 |
2008年 | 13篇 |
2007年 | 12篇 |
2006年 | 9篇 |
2005年 | 11篇 |
2004年 | 10篇 |
2003年 | 14篇 |
2002年 | 10篇 |
2001年 | 10篇 |
2000年 | 9篇 |
1999年 | 4篇 |
1998年 | 3篇 |
1997年 | 3篇 |
1996年 | 5篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 5篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 3篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1966年 | 1篇 |
1962年 | 1篇 |
排序方式: 共有389条查询结果,搜索用时 218 毫秒
81.
We discuss the design of interactive, internet based benchmarking using parametric (statistical) as well as non-parametric (DEA) models. The user receives benchmarks and improvement potentials. The user is also given the possibility to search different efficiency frontiers and hereby to explore alternative improvement strategies. Implementations of both a parametric and a non-parametric model are presented. 相似文献
82.
The manner in which a group of insurance risks are interrelated is commonly presented via a correlation matrix. Actuarial risk correlation matrices are often constructed using output from disparate modeling sources and can be subjectively adjusted, for example, increasing the estimated correlation between two risk sources to confer reserving prudence. Hence, while individual elements still obey the assumptions of correlation values, the overall matrix is often not mathematically valid (not positive semidefinite). This can prove problematic in using the matrix in statistical models. The first objective of this article is to review existing techniques that address the nearest positive semidefinite matrix problem in a very general setting. The chief approaches studied are Semidefinite Programming (SDP) and the Alternating Projections Method (APM). The second objective is to finesse the original problem specification to consider imposition of a block structure on the initial risk correlation matrix. This commonly employed technique identifies off-diagonal subsets of the matrix where values can or should be set equal to some constant. This may be due to similarity of the underlying risks and/or with the goal of increasing computational efficiency for processes involving large matrices. Implementation of further linear constraints of this nature requires adaptation of the standard SDP and APM algorithms. In addition, a new Shrinking Method is proposed to provide an alternative solution in the context of this increased complexity. “Nearness” is primarily considered in terms of two summary measures for differences between matrices: the Chebychev Norm (maximum element distance) and the Frobenius Norm (sum of squared element distances). Among the existing methods, adapted to function appropriately for actuarial risk matrices, APM is extremely efficient in producing solutions that are optimal in the Frobenius norm. An efficient algorithm that would return a positive semidefinite matrix that is optimal in Chebychev norm is currently unknown. However, APM is used to highlight the existence of matrices close to such an optimum and exploited, via the Shrinking Method, to find high-quality solutions. All methods are shown to work well both on artificial and real actuarial risk matrices provided under collaboration with Tokio Marine Kiln (TMK). Convergence speeds are calculated and compared and sample data and MATLAB code is provided. Ultimately the APM is identified as being superior in Frobenius distance and convergence speed. The Shrinking Method, building on the output of the APM algorithm, is demonstrated to provide excellent results at low computational cost for minimizing Chebychev distance. 相似文献
83.
Susana G. Azevedo Helena Carvalho V. Cruz Machado 《Transportation Research Part E: Logistics and Transportation Review》2011,47(6):850-871
The main objective of this exploratory paper is to investigate the relationships between green practices of supply chain management and supply chain performance. This relationship is investigated in the context of the automotive industry. Five research propositions are suggested and tested with empirical data derived from five case studies taken from the Portuguese automotive supply chain. The data analysis identifies the most important green practices considered by managers, as well as the performance measures that are most appropriate and most widely used as means to evaluate the influence of green practices on supply chain performance. A conceptual model was derived from the data analysis and it can be used to assess the influence of green practices on supply chain performance. This model provides evidence as to which green practices have positive effects on quality, customer satisfaction and efficiency. It also identifies the practices which have negative effects on supply chain performance. 相似文献
84.
The Return to Direct Investment in Private Firms: New Evidence on the Private Equity Premium Puzzle*
Kasper Meisner Nielsen 《European Financial Management》2011,17(3):436-463
This paper uses a novel dataset to analyze the return to direct investments in private firms by pension funds. We have two key findings. First, direct investments in private firms have underperformed public equity by 392 basis points per annum under conservative risk adjustments. Second, initial mispricing, due to over‐optimism or misperceived risk, and subsequent low capital gains seem to explain the gap in returns to private firms. Overall, these findings complement the finding of Moskowitz and Vissing‐Jørgensen (2002) of low returns on entrepreneurial investments and provide new insight into the existence of what they call the private equity premium puzzle: Even professional investors with well‐diversified portfolios like pension funds seem to get a poor risk‐return tradeoff from investing directly in private firms. 相似文献
85.
Mogens Bladt Bo Friis Nielsen Gennady Samorodnitsky 《Scandinavian actuarial journal》2013,2013(7):573-591
In this paper, we propose a class of infinite-dimensional phase-type distributions with finitely many parameters as models for heavy tailed distributions. The class of finite-dimensional phase-type distributions is dense in the class of distributions on the positive reals and may hence approximate any such distribution. We prove that formulas from renewal theory, and with a particular attention to ruin probabilities, which are true for common phase-type distributions also hold true for the infinite-dimensional case. We provide algorithms for calculating functionals of interest such as the renewal density and the ruin probability. It might be of interest to approximate a given heavy tailed distribution of some other type by a distribution from the class of infinite-dimensional phase-type distributions and to this end we provide a calibration procedure which works for the approximation of distributions with a slowly varying tail. An example from risk theory, comparing ruin probabilities for a classical risk process with Pareto distributed claim sizes, is presented and exact known ruin probabilities for the Pareto case are compared to the ones obtained by approximating by an infinite-dimensional hyper-exponential distribution. 相似文献
86.
Tine Buch-Kromann Martin Englund Jim Gustafsson Jens Perch Nielsen Fredrik Thuring 《Scandinavian actuarial journal》2013,2013(4):293-304
Not all claims are reported when a database for financial operational risk is created. The probability of reporting increases with the size of the operational risk loss, and converges towards one for big losses. Losses in operational risk have different causes, and usually follow a wide variety of distributional shapes. Therefore, a method for modelling operational risk based on one or two parametric models is deemed to fail. In this paper, we introduce a semi-parametric method for modelling operational risk that is capable of taking under-reporting into account and being guided by prior knowledge of the distributional shape. 相似文献
87.
Tina Gehlert Christiane Kramer Otto Anker Nielsen Bernhard Schlag 《Transport Policy》2011,18(5):685-694
Urban road pricing is regarded as an effective instrument to reduce traffic congestion and environmental-related problems in metropolitan areas. Whereas the overall impact of urban road pricing on car use adaptation and public acceptability is known, there are only inconsistent results concerning the socioeconomic differences in the response towards road pricing. However, this knowledge is necessary for the development of urban road pricing packages. This paper uses a segmentation approach to identify groups of car users with a similar background in relevant socioeconomic variables and compares their responses towards road pricing. Three groups are identified: young families, suburban families, and singles and couples. These groups indeed differ in their car use adaptation towards urban road pricing as well as in their preferred revenues use. While all three groups significantly reduced their private car use, the young families reduced their car use most, followed by the group of singles and couples. Complementary measures are discussed that are believed to facilitate car use adaptation of each group in response towards urban road pricing. 相似文献
88.
Has the Single Market for public procurement had the expected effects after six years in progress? The following article attempts to answer this question by first presenting alternative theoretical approaches to analysing the EU liberalisation of the public procurement market and then confronting these with the result of an empirical analysis. 相似文献
89.
90.
Richard P. Nielsen 《Journal of Business Ethics》2013,112(3):385-395
There are at least four important, institutional obstacles to whistle-blowing to regulatory institutions. First, regulatory institutions are often systematically understaffed and do not have the resources needed to adequately process whistle-blowing cases. Second, regulators who process whistle-blowing cases are often systematically inexperienced and do not understand the strategic importance of whistle-blowing cases. Third, regulators are often under systemic pressure from the politicians who appoint them to ignore whistle-blowing cases relevant to their sources of financial and/or ideological political support. Fourth, there are high systemic risks to whistle-blowers who blow the whistle to regulatory institutions. Nonetheless, understanding how the institutions and obstacles operate can help us understand what types of whistle-blowing methods can be used to navigate around the obstacles and within the regulatory institutions. In addition, sometimes whistle-blowing methods can help reform regulatory institutions. 相似文献