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91.
对两寡头厂商2元市场用完全信息动态博弈的方法分析了实施三度价格歧视情形和统一定价情形的均衡产量,均衡价格和均衡总收益,并研究了这两种情形三个指标之间的关系.结果显示,在两个子市场的需求函数为线性需求的条件下,统一定价的市场均衡产量等于歧视定价的市场均衡产量;统一定价的均衡价格是歧视定价时两个子市场均衡价格的加权平均;统一定价的市场均衡总收益小于歧视定价的市场均衡总收益.  相似文献   
92.
基于VAR模型,对碳市场中的EUA期货价格和CER期货价格的变动关系进行了实证研究.选取欧洲气候交易所(ECX)的EUA期货价格和CER期货价格作为研究对象,运用Johansen协整检验、Granger因果关系检验、向量误差修正模型、广义脉冲响应函数和方差分解方法形成递进式的计量分析框架.研究结果表明:第一,EUA期货价格与CER期货价格之间存在着相互影响关系;第二,CER期货价格对市场信息的反映比EUA期货价格更为敏感,反映速度更快;第三,两种价格之间,CER期货价格变动的影响起主导作用,更好地发挥了期货的定价功能,两市场间存在杠杆效应.  相似文献   
93.
试图将极端价格波动成因归结于系统惯性因素和极端随机冲击因素,借助Copulas-GARCH模型,将其引入期货和现货价格联动的计量模型之中,以持有便利收益高的沪铜作为研究样本,实证研究发现:1)引入极端价格波动因素后将显著提升价格联动计量模型的解释能力;2)当负向基差扩大,系统惯性因素引起商品价格剧烈变动,将导致市场联动性下降,而极端随机冲击却具有正向效应,即市场受到极端随机冲击时会增强期现价格联动关系;3)极端随机冲击效应中正向冲击和负向冲击的非对称性特征不显著;4)考虑极端价格波动效应可明显降低生产企业的套期保值成本.研究结论对于商品期货市场套期保值等期货交易具有重要管理启示.  相似文献   
94.
采用Khasminskii极限定理,随机平均法和FPK方程,研究了能源价格系统在随机干扰作用下的Hopf分岔特性,得到了分岔参数,并讨论了分岔参数对系统性态的影响.进而得出能源经济系统的相关结论.  相似文献   
95.
The risks and returns of stock investment are discussed via numerically simulating the mean escape time and the probability density function of stock price returns in the modified Heston model with time delay. Through analyzing the effects of delay time and initial position on the risks and returns of stock investment, the results indicate that: (i) There is an optimal delay time matching minimal risks of stock investment, maximal average stock price returns and strongest stability of stock price returns for strong elasticity of demand of stocks (EDS), but the opposite results for weak EDS; (ii) The increment of initial position recedes the risks of stock investment, strengthens the average stock price returns and enhances stability of stock price returns. Finally, the probability density function of stock price returns and the probability density function of volatility and the correlation function of stock price returns are compared with other literatures. In addition, good agreements are found between them.  相似文献   
96.
We construct a jump-diffusion model with seasonality, mean-reversion, time-dependent jump intensity and heteroskedastic disturbance for electricity spot prices, while keeping the analytical tractability of futures prices. We find that the jump component plays a considerably larger role than the diffusion component in the variance of spot prices. Moreover, the jump intensity is much higher during summer and winter. We also explore the seasonal market price of risk (MPR) with different maturities, from one month to five months. Our results show that the diffusion risk and the jump risk are priced quite differently.  相似文献   
97.
We investigate the continuity of expected exponential utility maximization with respect to perturbation of the Sharpe ratio of markets. By focusing only on continuity, we impose weaker regularity conditions than those found in the literature. Specifically, we require, in addition to the VV-compactness hypothesis of Larsen and ?itkovi? (2007) [13], a local bmobmo hypothesis, a condition which is essentially implicit in the setting of [13]. For markets of the form S=M+∫λd〈M〉S=M+λdM, these conditions are simultaneously implied by the existence of a uniform bound on the norm of λ⋅MλM in a suitable bmobmo space.  相似文献   
98.
At the ultra high frequency level, the notion of price of an asset is very ambiguous. Indeed, many different prices can be defined (last traded price, best bid price, mid price, etc.). Thus, in practice, market participants face the problem of choosing a price when implementing their strategies. In this work, we propose a notion of efficient price which seems relevant in practice. Furthermore, we provide a statistical methodology enabling to estimate this price from the order flow.  相似文献   
99.
Estimating the effect of price changes on demand is an essential task for retailers. This study proposes a methodology based on consumer utility for modeling the price thresholds phenomenon that allows for threshold asymmetry, incorporates consumer heterogeneity and uses weekly aggregated brand-level data. Unlike other studies based on consumer utility models, which generate results only for the price elasticity of market share, a methodology for estimating price elasticity of demand is also included. Data on fast-moving goods (detergents, toilet paper, soft drinks, meats, liquid juices and yogurts) supplied by a major retail chain are used to demonstrate the existence of price thresholds and their effects on price elasticity. In every case it was found that within the thresholds or latitude of acceptance, consumers are relatively less sensitive to price variations while beyond them a higher sensitivity was observed. In some cases a product brand was classified as inelastic within the latitude of acceptance and elastic outside of it.  相似文献   
100.
Abstract

Recently, several papers have expressed an interest in applying the Growth Optimal Portfolio (GOP) for pricing derivatives. We show that the existence of a GOP is equivalent to the existence of a strictly positive martingale density. Our approach circumvents two assumptions usually set forth in the literature: 1) infinite expected growth rates are permitted and 2) the market does not need to admit an equivalent martingale measure. In particular, our approach shows that models featuring credit constrained arbitrage may still allow a GOP to exist because this type of arbitrage can be removed by a change of numéraire. However, if the GOP exists the market admits an equivalent martingale measure under some numéraire and hence derivatives can be priced. The structure of martingale densities is used to provide a new characterization of the GOP which emphasizes the relation to other methods of pricing in incomplete markets. The case where GOP denominated asset prices are strict supermartingales is analyzed in the case of pure jump driven uncertainty.  相似文献   
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