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191.
192.
Michael Spacek 《Geopolitics》2014,19(3):609-631
This article situates India’s Maoist insurgency within longer term processes of state expansion in the east and centre of the country. Drawing on Henri Lefebvre’s work on space, its core claim is that since the onset of colonialism the region has been produced as a peripheral area whose primary function has been as a zone of settlement and a source of natural resources. Consequently the state has been simultaneously thin and repressive, leading to the creation of an oppositional insurgent space in which the Maoist guerrillas are only the most recent and visible actors. Currently new patterns of hyper-state and hybrid state/insurgent spaces are emerging: the former structured around the forced relocation of entire populations into tightly controlled and regulated camps and the latter around an emergent system of dual authority in which the demarcation between official and insurgent governance is blurred.  相似文献   
193.
The welcome rise of replication tests in economics has not been accompanied by a consensus standard for determining what constitutes a replication. A discrepant replication, in current usage of the term, can signal anything from an unremarkable disagreement over methods to scientific incompetence or misconduct. This paper proposes a standard for classifying one study as a replication of some other study. It is a standard that places the burden of proof on a study to demonstrate that it should have obtained identical results to the original, a conservative standard that is already used implicitly by many researchers. It contrasts this standard with decades of unsuccessful attempts to harmonize terminology, and argues that many prominent results described as replication tests should not be described as such. Adopting a conservative standard like this one can improve incentives for researchers, encouraging more and better replication tests.  相似文献   
194.
195.

Probability of informed trading (PIN) models characterize trading with certain types of information through a tree structure. Different tree structures with different numbers of groups for market participants have been proposed, with no clear, consistent tree used in the literature. One of the main causes of this inconsistency is that these trees are artificially proposed through a bottom-up approach rather than implied by actual market data. Therefore, in this paper, we propose a method that infers a tree structure directly from empirical data. More precisely, we use hierarchical clustering to construct a tree for each individual firm and then infer an aggregate tree through a voting mechanism. We test this method on US data from January 2002 for 7608 companies, which results in a tree with two layers and four groups. The characteristics of the resulting aggregate tree are between those of several proposed tree structures in the literature, demonstrating that these proposed trees all reflect only part of the market, and one should consider the proposed empirically driven method when seeking a tree representing the whole market.

  相似文献   
196.
Firms developing new products often face the challenge of making investment decisions under uncertain input–cost conditions due to the price volatilities of the materials they use. These decisions need to be made long before the final products are launched on the market. Therefore, firms that invest in the opportunity to switch materials in a timely manner will have the flexibility to react to material price changes and realize competitive advantages. However, volatile material prices may also cause a firm to delay investment. Using real‐options reasoning, this paper studies the influence of input‐cost fluctuations on the timing decision to start new product development (NPD) and thus create the follow‐on opportunity to later replace an existing product. A model that combines waiting and switching options to derive influencing factors of the flexibility value that triggers the investment is developed and tested on a sample of material substitution projects from manufacturing firms. The results show how price uncertainty of the new and the old material, their joint price development, the expected project duration, and competitive preemption are related to the propensity to delay the start of NPD. The findings provide new insights on how timing in adopting materials can be used to hedge exposure to volatile material prices. The insights are relevant for adopters and producers of new materials, as well as for policy makers who strive for supporting the diffusion of new materials.  相似文献   
197.
In about 20%–30% of cases where an analyst revises two outputs (namely, earnings estimates, target prices, or stock recommendations) simultaneously, the two estimates are revised in opposite directions. Existing literature notes that these inconsistent outputs are widespread, and concludes that they are lower-quality, driven by strategic bias, and are viewed as less valid by investors. We find that these characterizations are generally inaccurate. Apparent inconsistency is largely driven by accounting and economic factors, with only limited evidence that investment banking-related conflicts play a role. Moreover, inconsistent outputs are neither less accurate than consistent outputs nor do they resolve less investor uncertainty upon their release. Overall, our results suggest that researchers should be cautious in interpreting the correlation between analyst outputs as a measure of bias or quality, and in using a single analyst output as a proxy for an analyst's overall views.  相似文献   
198.
Despite recent interest in how psychiatric disorders affect work outcomes, little is known about the role of personality disorders (PDs), which are poorly understood yet prevalent (15%) and impairing. We used nationally representative data for 12,457 men and 16,061 women to examine associations of PDs with any employment, full-time employment, chronic unemployment, being fired or laid off, and having trouble with a boss or co-worker. Antisocial, paranoid, and obsessive-compulsive PDs demonstrated the broadest patterns of associations with adverse outcomes. Findings suggest that PDs may have implications for the productivity of co-workers as well as that of the disordered employees themselves.  相似文献   
199.
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   
200.
ABSTRACT

Previous research has demonstrated the comparative lack of priority fraud receives from government and law enforcement in the UK compared to other serious offences, as well as shortcomings in the overall approach to investigation. This paper examines the current state of affairs in the light of changes aimed at addressing these limitations. It incorporates findings from a national survey of police forces, as well as a local survey of police personnel in three forces supplemented by interviews. The findings suggest that the situation has become more complicated. Many police officers interviewed did not feel that the police response in their own area was effective, and that their colleagues often lacked the appropriate skill sets needed. Moreover, forces were not confident they were recruiting the right people to tackle fraud. The paper has important lessons for policing internationally.  相似文献   
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