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151.
人类对太湖湿地利用存在多种形式,但是在特定经济发展阶段的主导地位不同,存在太湖湿地利用阶段的演变,这个演变过程是在人类需求和湖泊湿地资源比较优势的共同作用下实现的,是实现丰富的自然资源对相对稀缺的自然资源的替代,是人造资本对自然资本和自然生产力进行替代的过程,是人类对太湖湿地依附性利用向和谐性利用转变的过程。 相似文献
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This paper proposes an approach to the intraday analysis of diversified world stock accumulation indices. The growth optimal portfolio (GOP) is used as reference unit or benchmark in a continuous financial market model. Diversified portfolios, covering the world stock market, are constructed and shown to approximate the GOP, providing the basis for a range of financial applications. The normalized GOP is modeled as a time transformed square root process of dimension four. Its dynamics are empirically verified for several world stock indices. Furthermore, the evolution of the transformed time is modeled as the integral over a rapidly evolving mean-reverting market activity process with deterministic volatility. The empirical findings suggest a rather simple and robust model for a world stock index that reflects the historical evolution, by using only a few readily observable parameters.
Mathematics Subject Classification: (1991) primary 90A12, secondary 60G30,62P20
JEL Classification: G10, G13 相似文献
154.
Models driven by Lévy processes are attractive because of their greater flexibility compared to classical diffusion models. First we derive the dynamics of the LIBOR rate process in a semimartingale as well as a Lévy Heath-Jarrow-Morton setting. Then we introduce a Lévy LIBOR market model. In order to guarantee positive rates, the LIBOR rate process is constructed as an ordinary exponential. Via backward induction we get that the rates are martingales under the corresponding forward measures. An explicit formula to price caps and floors which uses bilateral Laplace transforms is derived. 相似文献
155.
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157.
In this paper, we estimate ARFIMA–FIGARCH models for the major exchange rates (against the US dollar) which have been subject to direct central bank interventions in the last decades. We show that the normality assumption is not adequate due to the occurrence of volatility outliers and its rejection is related to these interventions. Consequently, we rely on a normal mixture distribution that allows for endogenously determined jumps in the process governing the exchange rate dynamics. This distribution performs rather well and is found to be important for the estimation of the persistence of volatility shocks. Introducing a time-varying jump probability associated to central bank interventions, we find that the central bank interventions, conducted in either a coordinated or unilateral way, induce a jump in the process and tend to increase exchange rate volatility. 相似文献
158.
Muammer Ozer 《Industrial Marketing Management》2003,32(6):517-530
New product development requires a long and detailed process with numerous activities such as product line planning, strategy development, concept generation and screening, business analysis, development, testing and validation, manufacturing development and commercialization. Furthermore, each of these activities has its own unique requirements, some requiring information collection from the market, whereas others requiring the collaboration of different people who are involved in the new product development activities. This paper investigates the Internet's role in these activities and develops research propositions. In addition, it discusses how the impact of the Internet might change based on different products and different organizational conditions. 相似文献
159.
Sven Rady 《Finance and Stochastics》1997,1(4):331-344
This paper uses a probabilistic change-of-numeraire technique to compute closed-form prices of European options to exchange
one asset against another when the relative price of the underlying assets follows a diffusion process with natural boundaries
and a quadratic diffusion coefficient. The paper shows in particular how to interpret the option price formula in terms of
exercise probabilities which are calculated under the martingale measures associated with two specific numeraire portfolios.
An application to the pricing of bond options and certain interest rate derivatives illustrates the main results. 相似文献
160.