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111.
This paper develops an estimation and testing framework for a stationary large panel model with observable regressors and unobservable common factors. We allow for slope heterogeneity and for correlation between the common factors and the regressors. We propose a two stage estimation procedure for the unobservable common factors and their loadings, based on Common Correlated Effects estimator and the Principal Component estimator. We also develop two tests for the null of no factor structure: one for the null that loadings are cross sectionally homogeneous, and one for the null that common factors are homogeneous over time. Our tests are based on using extremes of the estimated loadings and common factors. The test statistics have an asymptotic Gumbel distribution under the null, and have power versus alternatives where only one loading or common factor differs from the others. Monte Carlo evidence shows that the tests have the correct size and good power.  相似文献   
112.
This article studies optimal portfolio decisions with (long-term) liabilities for small open economy based investors, including the optimality of currency hedging (Walker (2008a). Chile is the home country of the representative investor, but results are likely to hold more generally. The problem is set up as in [Sharpe & Tint, 1990] and [Hoevenaars et al., 2007]. Hedging the liabilities and the consumption currency may imply optimal close-to-home biases, defined as overweighting asset classes which are highly correlated with local ones. The implementation challenges include: developing a methodology to estimate expected returns in local (real) currency; estimating the covariance matrix allowing for serial and crossed-serial correlations; and checking the results' robustness using a resampling method. The findings are: (i) portfolios always have optimal close-to-home biases, beyond the investment in local fixed income to hedge liabilities; (ii) currency hedging reduces investment in close-to-home asset classes, (iii) but has ambiguous effects on welfare — detected with the resampling method; (iv) currency hedged long-term US bonds are useful for hedging local interest rate risk; and (v) liabilities give access to high risk-return portfolios, not affecting otherwise the overall shape of the efficient regions. This article can be useful to investors based on small open economies, including pension funds, insurance companies, sovereign wealth funds and Central Banks.  相似文献   
113.
Previous studies indicate that nonprofit and for-profit hospitals provide comparable levels of uncompensated care, when taking into account their sizes. This evidence suggests that for-profit hospitals extract some indirect benefit when providing uncompensated care. Our article investigates how physician board membership affects uncompensated care provision. With data for hospitals in California from 1997 to 2010, we estimate a fixed-effect model where uncompensated care is a function of physician board membership, other board attributes, as well as hospital characteristics. Our results indicate that physician board membership in for-profit hospitals relates positively with uncompensated care provision. Prior evidence, such as Goldstein and Ward (2004) and Molinari et al. (1995), has shown that involving physicians in strategic decisions improves hospitals’ financial performance. Our results reinforce the notion that having physicians in leadership or strategic positions benefits for-profit hospitals. In these hospitals, physicians seem to understand the strategic component of providing uncompensated care, possibly due to their closer assessment of patients’ needs.  相似文献   
114.
The economic production quantity (EPQ) with shortage derived algebraically   总被引:1,自引:0,他引:1  
Previously, in several papers and textbooks, the classical economic order quantity (EOQ) and the economic production quantity (EPQ) formulas for the shortage case, have been derived using differential calculus and solving two simultaneous equations (derived from setting the two first partial derivatives to zero) with the need to prove optimality conditions with second-order derivatives. In a previous original piece of work, a new approach to find the EOQ with backlogging using some slight algebraic developments appeared. This paper extends the mentioned algebraic approach to the EPQ formula taking shortages into consideration within the case of only one backlog cost per unit and time unit. The final expressions provide the same formulas that are available in the classic textbooks on inventory theory.  相似文献   
115.
This article develops a real options model for valuing natural resource exploration investments (e.g. oil or copper) when there is joint price and geological‐technical uncertainty. After a successful several‐stage exploration phase, there is a development investment and an extraction phase. All phases are optimized contingent on price and geological‐technical uncertainty.
Several real options are considered. There are flexible investment schedules for all exploration stages and a timing option for the development investment. Once the mine is developed, there are closure, opening and abandonment options for the extraction phase. Our model maintains a relatively simple valuation structure by collapsing price and geological‐technical uncertainty into a one‐factor model.
We apply the model to a copper exploration prospect and find that a significant fraction of total project value is due to the operational, development and exploration options available to project managers.  相似文献   
116.
The future of deforestation in the Brazilian Amazon   总被引:2,自引:0,他引:2  
Concern about the future of Amazonian forests is growing as both the extent and rate of primary forest destruction increase. We combine spatial information on various biophysical, demographic and infrastructural factors in the Brazilian Amazon with satellite data on deforestation to evaluate the relative importance of each factor to deforestation in the region. We assess the sensitivity of results to alternative sampling methodologies, and compare our results to those of previous empirical studies of Amazonian deforestation. Our findings, in concert with those of previous studies, send a clear message to planners: both paved and unpaved roads are key drivers of the deforestation process. Proximity to previous clearings, high population densities, low annual rainfall, and long dry seasons also increase the likelihood that a site will be deforested; however, roads are consistently important and are the factors most amenable to policymaking. We argue that there is ample evidence to justify a fundamental change in current Amazonian development priorities if additional large-scale losses of forests and environmental services are to be avoided.  相似文献   
117.
A signalling model is presented that provides an additional explanation for the determination of call premia on corporate bonds. It is shown that firms may signal their exclusive information about their probability of default by the choice of their call premia. Stockholders of safer firms (i.e., those that have a lower probability of bankruptcy) have a higher incentive for providing a low call premium. This occurs because the call option will be valuable only if the firm survives by the first call date. This event, however, is more likely for the safer firm. The safer firm will therefore be more willing to sacrifice some current revenues (or equivalently, to provide a higher coupon than it would otherwise have to pay in order to sell the bond at par) by determining a lower call premium. The model therefore predicts a negative correlation between safety and call premia, a correlation that has been empirically confirmed by Fischer, Heinkel, and Zechner (1989). This correlation provides support to the signalling theory vis-à-vis the alternative explanation of taxes determining the call premia. Another contribution of this model is that it ties the call premium decision with expectations of future interest rates. Such expectations are considered important by practitioners, but were rarely considered in previous research.  相似文献   
118.
Patents and R&D as Real Options   总被引:2,自引:0,他引:2  
This article develops and implements a simulation approach to value patents and patent‐protected R&D projects based on the Real Options approach. It takes into account uncertainty in the cost‐to‐completion of the project, uncertainty in the cash flows to be generated from the project, and the possibility of catastrophic events that could put an end to the effort before it is completed. It also allows for the possibility of abandoning the project when costs turn out to be larger than expected or when estimated cash flows turn out to be smaller than anticipated. This abandonment option represents a very substantial part of the project's value when the project is marginal or/and when uncertainty is large. The model presented can be used to evaluate the effects of regulation on the cost of innovation and the amount on innovative output. The main focus of the article is the pharmaceutical industry. The framework, however, applies just as well to other research‐intensive industries such as software or hardware development.
(J.E.L.:G31, O22, O32).  相似文献   
119.
This paper considers the equilibrium pricing of equity-linked life insurance policies with an asset value guarantee; such policies provide for benefits which depend upon the performance of a reference portfolio subject to a minimum guaranteed benefit. The benefit is decomposed into a sure amount and an immediately exercisable call option on the reference portfolio. A numerical procedure for determining the value of the call option is presented and the risk minimizing investment strategy to be followed by the issuer of the policy is derived.  相似文献   
120.
The main effects of existing socioeconomic arrangements for agricultural land development in the Eastern Caribbean are discussed and changes aimed at improving both the efficiency and equity of the land development process are identified. The author argues that the existing ‘plantations-small holders’ structure is incapable of providing an efficient way of developing the available land resources and of improving the standard of living for the vast rural population. A new set of export oriented agricultural enterprises is pinpointed as a requirement in any viable solution aimed at taking land away from its present role as a resource for survival for the many and an economic benefit for the few and to reinstate agricultural lands as one of the key resources for more egalitarian, environmentally sound and efficient socioeconomic development.  相似文献   
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