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71.
This study explores the value of special issues by analyzing the characteristics of special issues of Telecommunications Policy (TP). Specifically, this study examines the status of special issue publications, the characteristics of their articles compared with those of general issues, and the factors affecting article citations. For the analysis, all information on TP articles published from 1976 to 2018 was collected from the Scopus database. A comparative analysis as well as a negative binomial regression were conducted on papers published after 1994, when the first special issue was published. The results show that special issues are distinguished from general issues by various characteristics, such as multinational author collaboration, number of references, keywords, and funding. While general issue papers are more frequently cited in academia, special issue papers show better performance in terms of online captures and social media sharing. Moreover, the smaller number of variables affects the frequency of citations in the case of special issues, revealing that content and format are more influential than author factors.  相似文献   
72.
《Telecommunications Policy》2017,41(10):931-947
Over the past two decades, China’s telecommunications industry has witnessed drastic market reform, steadfast institutionalization, and volatile technological changes, which have driven exponential industry expansion. This paper offers an updated longitudinal and comprehensive review on this reform process on the eve of 5G (the fifth generation mobile communications networks). First, the paper segments the two-decade reform crusade into discernible phases, each of which is embedded with different policy drives. These reform phases are then pattern-matched against the subtleties of the overall institutional, technological, and market backdrop. A series of policy issues are identified through a systematic examination of industry phenomena over the reform course. Finally, the status of research is assessed regarding China’s telecom industry and reform, based on which, knowledge gaps are identified and future research agenda suggested. Conclusions are made regarding future reform and research imperatives. The paper advances the understanding of China’s telecom reform, development, and the underlying policy issues. It updates and expands previous works on similar topics. Overall, this study provides important theoretical, managerial, and policy implications.  相似文献   
73.
Evidence assembled in this special issue of Food Policy shows that rising rural population densities in parts of Africa are profoundly affecting farming systems and the region’s economies in ways that are underappreciated in current discourse on African development issues. This study synthesizes how people, markets and governments are responding to rising land pressures in Africa, drawing on key findings from the various contributions in this special issue. The papers herein revisit the issue of Boserupian agricultural intensification as an important response to land constraints, but they also go further than Boserup and her followers to explore broader responses to land constraints, including non-farm diversification, migration, and reduced fertility rates. Agricultural and rural development strategies in the region will need to more fully anticipate the implications of Africa’s rapidly changing land and demographic situation, and the immense challenges that mounting land pressures pose in the context of current evidence of unsustainable agricultural intensification, a rapidly rising labor force associated with the region’s current demographic conditions, and limited nonfarm job creation. These challenges are manageable but will require explicit policy actions to address the unique development challenges in densely populated rural areas.  相似文献   
74.
Abstract:

In this paper, we provide a comparison of two models of temperature-based weather derivatives. The Alaton et al. model (2002) and the continuous-time autoregressive (CAR) model of Benth et al. (2007) are applied to temperature data from twelve cities in China. The objective is to determine which is the better model for temperature derivative modeling in Chinese cities. We found the CAR model to be more accurate in terms of normality of residuals and smaller relative errors. However, the shortcomings of both the Alaton et al. model and the CAR model are revealed in this study as well.  相似文献   
75.
This paper examines the impact of currency exchange rates on the carbon market. We scrutinize this effect through the European Union Emission Trading Scheme (EU-ETS), which primarily uses two substitutable fossil energy inputs for the generation of electricity: coal and natural gas. The European coal market is directly driven by global coal markets that are denominated in USD, whereas, natural gas is mainly imported from Russia and is denominated in Euros. The impulse response functions of a Structural Vector Autoregression (SVAR) model demonstrate that a shock in the Euro/USD exchange rate can be transmitted through the channel of energy substitution between coal and natural gas, and influence on the carbon credit market.  相似文献   
76.
The relative importance of permanent versus cyclical shocks to GDP has been found to depend on the presence or absence of a single break in mean growth. We estimate unobserved components models conditional on a trend break having occurred in any specified quarter and use the Bayesian model averaging to combine the conditional estimates. We estimate a break occurred around 2006:1. Allowing for a break significantly reduces estimates of trend variance. However, enough spread remains in the posterior distribution to indicate that available data does not definitively settle the question of the relative importance of trend versus cycle.  相似文献   
77.
We consider an insurance company whose surplus is represented by the classical Cramer-Lundberg process. The company can invest its surplus in a risk-free asset and in a risky asset, governed by the Black-Scholes equation. There is a constraint that the insurance company can only invest in the risky asset at a limited leveraging level; more precisely, when purchasing, the ratio of the investment amount in the risky asset to the surplus level is no more than a; and when short-selling, the proportion of the proceeds from the short-selling to the surplus level is no more than b. The objective is to find an optimal investment policy that minimizes the probability of ruin. The minimal ruin probability as a function of the initial surplus is characterized by a classical solution to the corresponding Hamilton-Jacobi-Bellman (HJB) equation. We study the optimal control policy and its properties. The interrelation between the parameters of the model plays a crucial role in the qualitative behavior of the optimal policy. For example, for some ratios between a and b, quite unusual and at first ostensibly counterintuitive policies may appear, like short-selling a stock with a higher rate of return to earn lower interest, or borrowing at a higher rate to invest in a stock with lower rate of return. This is in sharp contrast with the unrestricted case, first studied in Hipp and Plum, or with the case of no short-selling and no borrowing studied in Azcue and Muler.  相似文献   
78.
The neoclassical theory of investment implies that expected stock returns are tied with the expected marginal benefit of investment divided by the marginal cost of investment. Winners have higher expected growth and expected marginal productivity (two major components of the marginal benefit of investment), and earn higher expected stock returns than losers. The investment model succeeds in capturing average momentum profits, reversal of momentum in long horizons, long-run risks in momentum, and the interaction of momentum with several firm characteristics. However, the model fails to reproduce the procyclicality of momentum as well as its negative interaction with book-to-market equity.  相似文献   
79.
The aim of our research is to investigate the important role of banks in the governance of companies listed in the Euronext 100 index. Primarily, this research seeks to examine the impact of a bank’s presence within a firm, as a creditor or shareholder, on firm performance, as well as the motivations of banks to acquire holdings, and whether the presence of a bank as a shareholder of a firm facilitates its access to bank loans. Empirical analyses are conducted with a sample of 86 nonfinancial institutions listed in the Euronext 100 index over the period 2008–2013 using the three-stage least squares method. The study shows, first, that the presence of a bank within a firm, as a creditor or shareholder, is positively related to firm performance. Moreover, the firm’s performance is an important determinant of the presence of bank shareholding. Finally, the presence of a bank as a shareholder of a firm does not facilitate its access to bank loans.  相似文献   
80.
The core idea of life-cycle funds or target-date funds is to decrease the fund's equity exposure and conversely increase its bond exposure towards the fund's target date. Such funds have been gaining significant market share and were recently set as default choice of asset allocation in numerous defined contribution schemes or related old-age provision products in several countries. Hence, an assessment of life-cycle funds’ risk-return profiles – that is, the probability distribution of returns – is essential for sustainable financial planning of a large group of investors. This paper studies the risk-return profile of life-cycle funds in particular compared to simple balanced or lifestyle funds that apply a constant equity portion throughout the fund's term instead. In a Black–Scholes model, we derive balanced funds that reproduce the risk-return profile of an arbitrary life-cycle fund for single and regular contributions. We then analyze the accuracy of our results under more complex asset models with stochastic interest rates, stochastic equity volatility and jumps. We further show that frequently used ‘rule of thumb approximations’ that only take into account the life-cycle fund's average equity portion are not suitable to approximate a life-cycle fund's risk-return profile. Our results on the one hand facilitate sustainable financial planning and on the other hand challenge the very existence of life-cycle funds since appropriately calibrated balanced funds can offer a similar (often dominating) risk-return profile.  相似文献   
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