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1.
We identify farms’ optimal investment path in capital assets and compare it with their actual investment to assess the direction and extent of deviation from the optimal investment. A probit model is further used to investigate the determinants of the probability that a farmer over‐ or under‐invests in capital assets. We use a panel dataset of Dutch dairy farms over the period 2003–2013, and find that most farms under‐invest in capital assets during the study period. Although the number of farms that had over‐invested in capital assets is relatively small, these farms account for the biggest share of total investment in capital assets. The probit results show that liquidity, agricultural support payments, age, land tenure and standard output size are important variables explaining the likelihood of over‐and under‐investment.  相似文献   
2.
为了加快低密度奇偶校验(LDPC)码的译码速度,有效改善LDPC码的译码性能,针对校验节点更新过程中的对数似然比(LLR)值的大小,设计了一种LDPC码的动态加权译码方法。以IEEE 802.16e标准的奇偶校验矩阵为例,根据LLR值的变化规律,利用增长因子和抑制因子对和积译码算法和最小和译码算法进行动态加权。仿真结果显示,基于动态加权的译码方法相对于传统译码方法误码率都有明显改进,译码复杂度也有所降低。  相似文献   
3.
The advance of cryptocurrencies has sparked wide concern over their interplay with the existing global financial market. This paper analyzes the risk spillover relation between cryptocurrencies and major financial assets, and unravels how cryptocurrencies could influence global financial systemic risk. We find that cryptocurrencies function as a separate risk source from traditional assets. Major legislative, financial and technological events in the cryptocurrency market may affect risk spillover dynamics. Although the overall penetration of cryptocurrencies is not yet deep, introducing cryptocurrency can significantly increase the systemic risk to traditional markets during low risk level episodes.  相似文献   
4.
Integrating signalling theory and the portfolio diversity literature, we theorize that diversity in a firm's patent and alliance portfolios sends contrasting flow signals impacting its market value in a nuanced way. Diversity in an alliance portfolio mediates the patent portfolio diversity – market value relationship by suppressing the negative effect of patent portfolio diversity creating an overall positive effect. We test our mediation model on a longitudinal set of 225 US biopharmaceutical firms that were awarded 17,078 patents and participated in 37,744 alliances between 1990 and 2006. Our theory and findings contribute three novel insights. First, we demonstrate the value of a temporal lens in explaining why diversity in a firm's patent and alliance portfolios send flow signals that establish expectations among market observers and have performance implications. Second, establishing that patent and alliance portfolio diversity are temporally sequenced provides compelling evidence for the value of studying multiple types of portfolios, their temporal relationships and effects on firm outcomes. Third, since diversity in a firm's portfolios can send contrasting flow signals conditioned on the cognitive demands and proximity involved in interpreting the signals, firms that do not maintain a ‘signalling fit’ with market observers increase the probability of unintentional negative signalling effects.  相似文献   
5.
宋敏  史婷  王茜 《水利经济》2018,36(6):20-25
明确港口腹地演变趋势、分析港腹耦合协调度,对长三角地区港腹联动发展具有重要意义。量化港口系统—腹地系统综合指标评价体系,运用高斯烟羽模型在2006、2011、2016年3个时间节点上测算长三角地区主要港口影响强度,并对腹地范围进行划分,利用耦合协调模型定量分析港口系统和直接腹地经济系统耦合协调度。研究结果表明:长三角地区港口呈现"一超多强"的格局,以上海港为中心,各港口多极发展;港口腹地范围整体稳定,局部波动,上海港的边缘腹地不断缩减;港口与腹地的耦合协调度处于上升态势,宁波—舟山港腹耦合协调度最高。  相似文献   
6.
We develop an open-economy New Keynesian Model with foreign exchange (FX) intervention in the presence of a financial accelerator and shocks to risk appetite in international capital markets. We obtain closed-form solutions for optimal monetary and FX intervention policies assuming the central bank cannot commit to future policies, and we compare the solution to that under policy commitment. We show how FX intervention can help reduce the volatility of the exchange rate, of inflation, and of the output gap, thus mitigating welfare losses associated with shocks in the international capital markets. We also show that, when the financial accelerator is strong, there is a risk of indeterminacy (self-fulfilling currency and inflation movements) although FX intervention can reduce this risk and thus reinforce the credibility of the inflation targeting regime. Model simulations match well the impact of a VIX shock obtained by local projections on a panel of inflation targeting emerging markets.  相似文献   
7.
党的十九大报告首次提出区域协调发展战略,要求各地充分发挥比较优势,加强政府间合作,着力解决区域发展不平衡不充分的问题。深汕合作区正是实施这一战略的典型代表。其中,政府的战略政策导向、经济全球化、区域一体化和非政府组织的发展是合作区得以形成的主要外部动力;区域协调发展、产业结构调整、官员升迁诉求是内部动力。但是,在合作区发展的过程中也存在一定的阻力。如地方保护主义的抬头、利益博弈、市场运作的行政化。因此,为促进地方政府间良性合作,应不断强化合作的正向激励,降低合作的阻力,保证区域府际合作的长久性。  相似文献   
8.
We show that speed limit policy, a monetary policy strategy that focuses on stabilizing inflation and the change in the output gap, consistently outperforms flexible inflation targeting and flexible price level targeting in empirical medium‐scale DSGE models under discretionary policymaking. In contrast to small‐scale New Keynesian models, this welfare ranking of the targeting frameworks is not overturned when inflation dynamics are mostly backward‐looking. Importantly, the performance of the speed limit policy shows less sensitivity to its parameterization than other frameworks that target the inflation rate or the price level.  相似文献   
9.
In an unexpected outcome, UK voters decided that it was time to exit the European Union based on the results of a vote held on 23 June 2016. Studies of the affects and implication of Brexit include a study showing that the vote was met with a negative short-term wealth effect for UK American depository receipts (ADRs). This study examines the one-year anniversary holding period returns of these ADRs along with the British Pound and the FTSE 100 to discover any lingering effects from the historical vote. Results indicate that the one-year holding period returns for the ADRs averaged 5.8% for the year while the FTSE gained 4.8%, the S&P 500 gained 15.4% and the Pound lost 13.2% of its value.  相似文献   
10.
We derive the asymptotic distribution for the LU decomposition, that is, the Cholesky decomposition, of realized covariance matrix. Distributional properties are combined with an existing generalized heterogeneous autoregressive (GHAR) method for forecasting realized covariance matrix, which will be referred to as a generalized HARQ (GHARQ) method. An out-of-sample forecast comparison of a real data set shows that the proposed GHARQ method outperforms other existing methods in terms of optimizing the variances of portfolios.  相似文献   
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