全文获取类型
收费全文 | 53824篇 |
免费 | 2256篇 |
国内免费 | 671篇 |
专业分类
财政金融 | 3773篇 |
工业经济 | 2555篇 |
计划管理 | 12674篇 |
经济学 | 9893篇 |
综合类 | 8014篇 |
运输经济 | 441篇 |
旅游经济 | 923篇 |
贸易经济 | 6388篇 |
农业经济 | 5428篇 |
经济概况 | 6662篇 |
出版年
2024年 | 92篇 |
2023年 | 689篇 |
2022年 | 1002篇 |
2021年 | 1545篇 |
2020年 | 1863篇 |
2019年 | 1216篇 |
2018年 | 1067篇 |
2017年 | 1141篇 |
2016年 | 1266篇 |
2015年 | 1529篇 |
2014年 | 3973篇 |
2013年 | 4360篇 |
2012年 | 4646篇 |
2011年 | 5614篇 |
2010年 | 4225篇 |
2009年 | 3488篇 |
2008年 | 3546篇 |
2007年 | 3088篇 |
2006年 | 3017篇 |
2005年 | 2242篇 |
2004年 | 1515篇 |
2003年 | 1346篇 |
2002年 | 968篇 |
2001年 | 945篇 |
2000年 | 638篇 |
1999年 | 378篇 |
1998年 | 199篇 |
1997年 | 168篇 |
1996年 | 155篇 |
1995年 | 120篇 |
1994年 | 108篇 |
1993年 | 76篇 |
1992年 | 61篇 |
1991年 | 51篇 |
1990年 | 30篇 |
1989年 | 22篇 |
1988年 | 27篇 |
1987年 | 9篇 |
1986年 | 7篇 |
1985年 | 70篇 |
1984年 | 80篇 |
1983年 | 51篇 |
1982年 | 52篇 |
1981年 | 20篇 |
1980年 | 18篇 |
1979年 | 16篇 |
1978年 | 5篇 |
1977年 | 6篇 |
1973年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
While broadband is widely believed to augment productivity, there is little firm-level evidence of a generalised causal effect. In this paper we examine whether the introduction of digital subscriber line (DSL) broadband services increased firms' productivity in nine sub-sectors within the services and distribution sector in Ireland from 2006 to 2012. Firm-level panel data on firms' characteristics are linked to spatial information on the rollout of DSL. While we do not find significant productivity effects in the services sectors taken together, we do find positive and significant effects on firm's total factor productivity in Information & Communication and Administrative & Support Services. 相似文献
62.
This paper studies the expansion of an option price (with bounded Lipschitz payoff) in a stochastic volatility model including a local volatility component. The stochastic volatility is a square root process, which is widely used for modeling the behavior of the variance process (Heston model). The local volatility part is of general form, requiring only appropriate growth and boundedness assumptions. We rigorously establish tight error estimates of our expansions, using Malliavin calculus. The error analysis, which requires a careful treatment because of the lack of weak differentiability of the model, is interesting on its own. Moreover, in the particular case of call–put options, we also provide expansions of the Black–Scholes implied volatility that allow to obtain very simple formulas that are fast to compute compared to the Monte Carlo approach and maintain a very competitive accuracy. 相似文献
63.
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
64.
Declining unionization rates and job polarization are two important labor market developments of recent decades. A large body of literature has analyzed these phenomena separately, but little has been done to see whether there is a link between them. We employ a macroeconomic model for a small open economy with a large input–output core to analyze how deunionization may cause job polarization. Our analysis shows that medium-skilled workers are negatively affected by deunionization, mainly as a result of the heterogeneity of the elasticities of substitution between different types of labor. While the elasticities of substitution between high- and medium-skilled labor are relatively low, the elasticities of substitution between medium- and low-skilled are relatively high. As a result, when deunionization leads to increased wage dispersion, we find that demand for low-skilled increases at the expense of medium-skilled labor, thus yielding a more polarized labor market. 相似文献
65.
闽侯县闲置农地生态安全评价研究 总被引:1,自引:0,他引:1
[目的]根据闽侯县农用地闲置情况,结合当地社会经济及生态环境发展情况,深入分析闽侯县闲置农地的生态安全发展水平。[方法]建立闽侯县闲置农地生态安全评价指标体系,分别从农村垃圾处理点数量、财政支农资金、外部进入农村投资、农业生产总值、种粮补贴、自然灾害、农业技术水平、农村生物的多样性程度、农村家庭收入结构、农村生态补偿金额、农地的整理规模及环保支出占GDP比重共确定12个指标进行深入研究,运用普通最小二乘法对设计的多元线性回归模型进行回归,进一步对闽侯县闲置农地的生态安全水平进行评价。[结果]农村垃圾处理点数量、财政支农资金、种粮补贴、环保支出占GDP比重、生态补偿金额、生物多样性程度对闽侯县闲置农地生态安全水平起到促进作用,呈正相关趋势;自然灾害则与闲置农地生态安全水平呈负相关趋势。[结论]整体看来,闽侯县闲置农地的生态安全水平主要受到当地经济、环境及生态基础三大因素的影响。 相似文献
66.
Tien-Shih Hsieh Zhihong Wang Sebahattin Demirkan 《Journal of Accounting and Public Policy》2018,37(3):241-253
We investigate how overconfident CEOs and CFOs may interact to influence firms’ tax avoidance. We adopt an equity measure to capture overconfident CEOs and CFOs and utilize multiple measures to identify companies’ tax-avoidance activities. We document that CFOs, as CEOs’ business partners, play an important role in facilitating and executing overconfident CEOs’ decisions in regard to tax avoidance. Specifically, we find that companies are more likely to engage in tax-avoidance activities when they have both overconfident CEOs and overconfident CFOs, compared with companies that have other combinations of CEO/CFO overconfidence (e.g., an overconfident CEO with a non-overconfident CFO), which is consistent with the False Consensus Effect Theory. Our study helps investors, regulators, and policymakers understand companies’ decision-making processes with regard to tax avoidance. 相似文献
67.
新制度经济学视角下的中国农地制度变迁:回顾与展望 总被引:1,自引:0,他引:1
研究目的:分析总结中国农地制度变迁的路径特征、决定条件和影响因素,并展望进一步研究方向。研究方法:文献分析法。研究结果:(1)改革开放以来的中国农地制度变迁呈现出一个较清晰的路径,即改革始终沿着市场取向、明晰产权、稳定地权的方向演进;(2)农地使用权制度改革的成功源于诱致性变迁与强制性变迁的结合,即弹性的中央政策制定、渐进式的地方实施以及具有学习效应的农户认知三者的有机互动,并体现出制度变迁的"共生演化"特征及其蕴含的"适应性效率";(3)新制度经济学是解释中国经济改革和农地制度变迁的有效工具,然而由于经典的新制度经济学本质上的静态性以及国家理论的缺乏,难以对现实世界的各类制度变迁给出一般化的解释。研究结论:基于经典的新制度经济学,进一步整合行为经济学、机制设计理论、演化博弈论等理论工具,超越"强制性—诱致性变迁"二分法,构建一个真正动态的制度变迁模型是一个重要研究方向。 相似文献
68.
Alexander S. Gorbenko 《Journal of Financial Economics》2019,131(1):88-117
Differences among bidder type-specific outcomes of asset sales are theoretically related to differences in bidders’ valuations and participation. The lead application to quantify these relations is takeover auctions: bidders are classified into strategic and financial, and bids are available. I structurally estimate valuations from all bids. The positive difference in premiums between strategic and financial acquirers is driven by the difference in dispersions of valuations (e.g., strategic bidders’ synergies are more dispersed) and the set of auction participants. The difference in average valuations is relatively unimportant. My approach can help explain outcomes of asset sales, even in settings with limited bidder data. 相似文献
69.
研究目的:剖析农村土地制度和农业经营制度的关系,为完善农村基本经营制度提供参考。研究方法:比较分析法、文献研究法。研究结果:新中国成立70年来,农村基本经营制度先后历经新中国成立初期的"农民所有、家庭经营"、改革开放前期的"集体所有、集体经营"到改革开放后期的"集体所有、均田承包、家庭经营",再到现阶段的"集体所有、均田承包和多元经营"4个阶段。在这个过程当中,农村基本经营制度既遵循人口与土地关系、生存与发展关系以及政府与市场关系的大逻辑,又遵循着农村土地制度的"产权逻辑"、农业经营制度的"生产逻辑"等小逻辑。研究结论:为深化农村基本经营制度变革,需加强农村土地制度与农业经营制度联动改革的制度设计,发挥要素、组织和制度的作用,发展多种形式的适度规模经营,实现小农户与现代农业发展的有机衔接。 相似文献
70.
粮食主产区耕地健康产能评价 ——以河南省温县为例 总被引:6,自引:0,他引:6
研究目的:探寻适合中国新时代耕地产能评价的新理论与方法,界定耕地健康产能内涵,构建评价指标体系,并应用河南省温县验证。研究方法:基于"需求—功能—维度—要素—指标"理论框架,构建耕地健康产能评价指标体系,运用综合算法、"1+X"累加模型法、图层叠加法定量评价耕地健康产能。研究结果:(1)温县耕地产能和耕地健康诊断结果地域分异特征明显,以青峰岭为界,北部耕地产能和健康状况较南部好;(2)耕地健康产能整体状况良好,乡镇间差异明显;(3)耕地健康产能结果更多取决于耕地健康诊断,主要受耕地生产环境和耕地系统弹性影响。研究结论:耕地健康产能评价指标体系和评价方法有应用性。 相似文献