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551.
An employer that sets up a defined benefit pension plan promises to periodically pay a certain sum to each participant starting at some future date and continuing until death. Although both the future beneficiary and the employer can be asked to finance the plan throughout the beneficiary's career, any shortcoming of funds in the future is often the employer's responsibility. It is therefore essential for the employer to be able to predict with a high degree of confidence the total amount that will be required to cover its future pension obligations. Applying mortality forecasting models to the case of the Royal Canadian Mounted Police pension plan, we illustrate the importance of mortality forecasting to value a pension fund's actuarial liabilities. As future survival rates are uncertain, pensioners may live longer than expected. We find that such longevity risk represents approximately 2.8 percent of the total liability ascribable to retired pensioners (as measured by the relative value at risk at the 95th percentile) and 2.5 percent of the total liabilities ascribable to current regular contributors. Longevity risk compounds the model risk associated with not knowing what is the true mortality model, and we estimate that model risk represents approximately 3.2 percent of total liabilities. The compounded longevity risk therefore represents almost 6 percent of the pension plan's total liabilities.  相似文献   
552.
553.
Abstract

Aims: To evaluate the cost-effectiveness of percutaneous patent foramen ovale (PFO) closure, from a US payer perspective. Lower rates of recurrent ischemic stroke have been documented following percutaneous PFO closure in properly selected patients. Stroke in patients aged <60?years is particularly interesting because this population is typically at peak economic productivity and vulnerable to prolonged disability.

Materials and methods: A Markov model comprising six health states (Stable after index stroke, Transient ischemic attack, Post-Transient Ischemic Attack, Clinical ischemic stroke, Post-clinical ischemic stroke, and Death) was constructed to evaluate the cost-effectiveness of PFO closure in combination with medical management versus medical management alone. The base-case model employed a 5-year time-horizon, with transition probabilities, clinical inputs, costs, and utility values ascertained from published and national costing sources. Incremental cost-effectiveness ratio (ICER) was evaluated per US guidelines, utilizing a discount rate of 3.0%.

Results: At 5?years, overall costs and quality-adjusted life-years (QALYs) obtained from PFO closure compared with medical management were $16,323 vs $7,670 and 4.18 vs 3.77, respectively. At 5?years, PFO closure achieved an ICER of $21,049, beneficially lower than the conventional threshold of $50,000. PFO closure reached cost-effectiveness at 2.3?years (ICER = $47,145). Applying discount rates of 0% and 6% had a negligible impact on base-case model findings. Furthermore, PFO closure was 95.4% likely to be cost-effective, with a willingness-to-pay (WTP) threshold of $50,000 and a 5-year time horizon.

Limitations: From a cost perspective, our economic model employed a US patient sub-population, so cost data may not extrapolate to other non-US stroke populations.

Conclusion: Percutaneous PFO closure plus medical management represents a cost-effective approach for lowering the risk of recurrent stroke compared with medical management alone.  相似文献   
554.
We apply a multi-equation dynamic econometric model on monthly data to test if the behaviour of OPEC as a whole or different sub-groups of the cartel is consistent with the characteristics of dominant producers on the world crude oil market in the period 1973–2001. Our results indicate that the producers outside OPEC can be described as competitive producers, taking the oil price as given and maximizing profits. The OPEC members do not fit the behaviour of price-taking producers. Our findings of low residual demand price elasticities for OPEC underpin the potential market power of the producer group, and are in line with the results in some recent energy studies. On the other hand, our findings indicate that neither OPEC nor different sub-groups of the cartel can be characterized as a dominant producer in the period 1973–1994. However, we find that the characteristics of a dominant producer to some extent fit OPEC-Core as from 1994. Thus, although OPEC clearly has affected the market price, the producer group has not behaved as a pure profit-maximizing dominant producer.  相似文献   
555.
In the innovation studies literature, innovation patterns have been described, such as science-based and practice-based innovation, that vary among industrial sectors. As a consequence, firms become distinguished with respect to their typical innovation pattern. Less attention has been paid to the possibility of intertwined innovation patterns. Focusing on public sector services, this paper argues that intertwined innovation patterns emerge within public services as a response to value-tensions. Values can be defined as measures for beneficial behaviour that guide innovation. Value-tensions in public services include tensions between the political, economic, communal, aesthetic and intellectual values. The contribution of the paper to service innovation research is the emphasis on the concept of intertwined innovation patterns, such as the intertwinement of science-driven and task-driven innovation. Furthermore, the paper contributes by pinpointing how varied values guide innovation in public services.  相似文献   
556.
In a gravity model for 184 countries between 1990 and 2005, we show that bilateral aid is not only positively correlated with donor exports, as suggested in earlier studies, but also positively associated with recipient exports to donors. Our interpretation is that an intensified aid relation reduces the effective cost of distance. We find a particularly strong effect of aid in the form of technical assistance. The effect of trade-related assistance (Aid for Trade) is small and fully accounted for by aid to investments in trade-related infrastructure. The aid-trade link is particularly strong for donor exports to Sub-Saharan African countries and for recipient exports of strategic materials.  相似文献   
557.
The regulatory debate concerning high-frequency trading (HFT) emphasizes the importance of distinguishing different HFT strategies and their influence on market quality. Using data from NASDAQ-OMX Stockholm, we compare market-making HFTs to opportunistic HFTs. We find that market makers constitute the lion's share of HFT trading volume (63–72%) and limit order traffic (81–86%). Furthermore, market makers have higher order-to-trade ratios and lower latency than opportunistic HFTs. In a natural experiment based on tick size changes, we find that the activity of market-making HFTs mitigates intraday price volatility.  相似文献   
558.
We investigate whether and how financial constraints of private firms depend on bank lending behavior. Bank lending behavior, especially its scale, scope and timing, is largely driven by bank business models which differ between privately owned and state-owned banks. Using a unique dataset on private small and medium-sized enterprises (SMEs) we find that an increase in relative borrowings from local state-owned banks significantly reduces firms’ financial constraints, while there is no such effect for privately owned banks. Improved credit availability and private information production are the main channels that explain our result. We also show that the lending behavior of local state-owned banks can be sustainable because it is less cyclical and neither leads to more risk taking nor underperformance.  相似文献   
559.
This article provides a comprehensive critique of current corporate foreign exchange risk management (FXRM) practices. The authors characterize much of FXRM as a “legacy” activity, a set of outdated, often decentralized and “earnings‐driven” methods and procedures that have not been subjected to rigorous cost‐benefit analysis at the enterprise level. And according to the authors, the costs of poorly designed and executed FXRM have increased sharply in recent decades because of the growing demand by analysts and investors for cost‐efficiency, transparency, and predictability. After discussing six ways in which the FX policy of most large multinationals fails to serve the interests of their investors and other important stakeholders, the authors offer the following: (1) a restatement of the goals of FXRM; (2) an illustration of various ways of implementing a largely (if not completely) centralized approach to FXRM; (3) a proposal for aligning performance evaluation and executive pay with the goals of FXRM; (4) suggestions for improving decision‐support tools in relation to FXRM; (5) proposals for integrating FXRM into an enterprise‐wide risk management system, which include shifting responsibility for FXRM from the Finance/Treasury group to a centralized risk committee (typically under a Chief Risk Officer who reports to the board of directors); and (6) suggestions for improving communication of a company's risk management policies and practices to investors and other stakeholders.  相似文献   
560.
This paper introduces a concept of inequality comparisons with ordinal bivariate categorical data. In our model, one population is more unequal than another when they have common arithmetic median outcomes and the first can be obtained from the second by correlation‐increasing switches and/or median‐preserving spreads. For the canonical 2 × 2 case (with two binary indicators), we derive a simple operational procedure for checking ordinal inequality relations in practice. As an illustration, we apply the model to childhood deprivation in Mozambique.  相似文献   
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