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1.
Mijatovi? and Pistorius proposed an efficient Markov chain approximation method for pricing European and barrier options in general one‐dimensional Markovian models. However, sharp convergence rates of this method for realistic financial payoffs, which are nonsmooth, are rarely available. In this paper, we solve this problem for general one‐dimensional diffusion models, which play a fundamental role in financial applications. For such models, the Markov chain approximation method is equivalent to the method of lines using the central difference. Our analysis is based on the spectral representation of the exact solution and the approximate solution. By establishing the convergence rate for the eigenvalues and the eigenfunctions, we obtain sharp convergence rates for the transition density and the price of options with nonsmooth payoffs. In particular, we show that for call‐/put‐type payoffs, convergence is second order, while for digital‐type payoffs, convergence is generally only first order. Furthermore, we provide theoretical justification for two well‐known smoothing techniques that can restore second‐order convergence for digital‐type payoffs and explain oscillations observed in the convergence for options with nonsmooth payoffs. As an extension, we also establish sharp convergence rates for European options for a rich class of Markovian jump models constructed from diffusions via subordination. The theoretical estimates are confirmed using numerical examples.  相似文献   
2.
本文在一个三阶段动态博弈框架下,对政府随机审计过程中的政府审计机关与政府审计对象以及国家与政府审计对象之间的动态博弈特征进行了分析。分析结果显示:政府审计机关与政府审计对象之间存在一个纯策略纳什均衡,而国家和政府审计对象之间存在一个混合策略纳什均衡。政府审计对象接受国家实质性审计的概率是政府审计对象被政府机关审计发现违规或不作为后的惩罚倍数的单调递减函数,而政府审计对象的违规或不作为的概率分别是政府审计对象被政府机关审计发现违规或不作为后的惩罚倍数和政府审计对象的应尽义务或责任的单调递减函数,却是政府审计机关审计行为成本的单调递增函数。同时,结合研究结论和中国政府审计全覆盖的现实,给出了一些政策建议。  相似文献   
3.
Using economic analysis to prioritise improvements in environmental conditions is particularly difficult when multiple benefits are involved. This includes ‘bundling’ issues in agricultural pollution management, where a change in management action or farming systems generates multiple improvements, such as reductions in more than one pollutant. In this study, we conceptualise and compare two different approaches to analysing cost‐effectiveness when varying bundles of benefits are generated for a single project investment. Each approach requires data to be transformed in some way to allow the analysis to proceed. The index approach requires the transformation on the benefits side so that the effects of multiple pollutant changes can be combined into a measure for each project which can then be compared to costs. By comparison, the disaggregation approach requires the transformation on the costs side where costs for each project have to be apportioned across the different pollutants involved. The paper provides novel insights with an application to agricultural water quality improvements into the Great Barrier Reef in Australia, demonstrating that while both approaches are effective in prioritising projects by cost‐effectiveness, the disaggregation approach provides more insightful results and values that may be relevant for use as upper value guidelines in future project selection.  相似文献   
4.
This study investigates the connection between corporate social responsibility (CSR) and corporate reputation among the public using fuzzy set qualitative comparative analysis (fsQCA). To examine complex processes underlying the reactions of this influential stakeholder group, hypotheses are drawn from the category diagnosticity approach. Thereby, a psychological model of perceived (im)morality is transferred to the CSR context. In line with these hypotheses, positive/negative CSR activities influence reputation in the expected directions (H1a, b), while the effects of specific configurations of CSR activities reveal an asymmetry suggesting a negativity bias (H2). Further analyses confirm that positive effects require a consistent positive performance regarding prior reputations (H3a) and the aggregated CSR activities of several previous years (H3b, c). Moreover, the relevant patterns vary between industries (H4). The present study thus contributes to CSR research by investigating a powerful but hitherto understudied stakeholder group through a category diagnosticity lens combined with a configurational approach to analysis.  相似文献   
5.
An important initial step in accounting is mapping financial transfers to the corresponding accounts. We devised machine-learning-based systems that automate this process. They use word embeddings with character-level features to process transaction texts. When considering 473 companies independently, our approach achieved an average top-1 accuracy of 80.50%, outperforming baselines that exclude the transaction texts or rely on a lexical bag-of-words text representation. We extended the approach to generalizes across companies and even across different corporate sectors. After standardization of the account structures and careful feature engineering, a single classifier trained on 44 companies from 28 sectors achieved a test accuracy of more than 80%. When trained on 43 companies and tested on the remaining one, the system achieved an average performance of 64.62%. This rate increased to nearly 70% when considering only the largest sector.  相似文献   
6.
为了解决同时含有随机因素和灰色因素的不确定规划问题,通过结合区间灰数所属区间两个端点的随机性,给出随机区间灰数和随机区间灰函数的定义,提出了随机灰规划模型。通过综合效应函数理论用随机变量期望值和方差综合量化表示灰数所属区间的两个端点值。应用该理论对综合量化后的两个端点值继续进行综合量化,从而将随机灰规划转化为确定型规划问题。应用遗传算法进行求解。通过综合效应函数的理念,综合随机变量的期望和方差,同时综合区间灰数的区间因素,将随机灰规划数学模型转化为确定型规划模型即基于效应的随机灰规划模型。通过选取不同的综合效应函数,得到了关于不同决策意识下的随机灰规划的最优解。这个方法可为决策者进行不确定决策提供参考。  相似文献   
7.
董丽娟 《科技和产业》2020,20(9):219-224
城市道路下穿铁路框架桥顶进施工的关键是合理控制桥梁主体结构的受力。为了对框架桥顶进施工过程进行受力特性分析,采用Midas有限元软件模拟了框架桥在滑板上开始顶进、框架桥重心即将离开滑板、框架桥顶进即将就位三个施工阶段。结果表明,该框架桥的施工过程是安全可靠的,同时结合工程项目实际给出了顶进施工的注意事项。该方法可用来指导类似工程顶进施工过程的受力分析和施工控制。  相似文献   
8.
We review a rich class of point process models, Cox point processes, and illustrate the necessity of more than one observation (point patterns) in performing parameter estimation. Furthermore, we introduce a new Cox point process model by treating the intensity function of the underlying Poisson point process as a random mixture of normal components. The behaviour and performance of the new model are compared with those of popular Cox point process models. The new model is exemplified with an application that involves a single point pattern corresponding to earthquake events in California, USA.  相似文献   
9.
This study assesses supplier selection at the beginning of project management to establish an evaluation system corresponding to blockchain tracing anti-counterfeiting platforms (BTAP). First, this paper determines 20 evaluation criteria from the four dimensions of platform overview, core technology, application support, and operations management. On this basis, multi-criteria decision making (MCDM) based on customer needs is proposed, which consists of three main steps. First, quality function deployment (QFD) and the best and worst method (BWM) are used to evaluate the four dimensions of the BTAP and specific evaluation criteria from the perspective of customers to obtain the criteria weight. Then, this method uses the extended Vlse Kriterjumska Optimizacija I Kompromisno Resenje (VIKOR) approach to sort the alternatives. Finally, the improved decision making trial and evaluation laboratory (DEMATEL) method is used to analyse the relationships between the 20 criteria in the four dimensions. The feasibility and effectiveness of this method are verified by an example. According to the sensitivity analysis and comparative analysis, the results show that this method can evaluate blockchain anti-counterfeiting enterprises. The main conclusions are as follows: the core technology is the most important factor influencing the choice of a BTAP project, and the role of application support in evaluation cannot be ignored.  相似文献   
10.
ABSTRACT

This paper seeks to compare the capabilities of assorted measures of consumer and economic sentiment in predicting the growth of household expenditure. An analysis of quarterly data on five European countries shows that for none of these can the model which incorporates the EU’s headline consumer confidence indicator be deemed to be significantly inferior to any of its seven rivals. However, the rankings of the sentiment variables are seen to be influenced by: the proportion of total spending by households that is devoted to durable goods; and the nature of the behaviour of consumption over the forecast interval.  相似文献   
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