The Laplace Distribution and Generalizations: A Revisit With Applications to Communications, Economics, Engineering, and Finance
The Laplace Distribution and Generalizations: A Revisit With Applications to Communications, Economics, Engineering, and Finance
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DOI:
10.1198/jasa.2002.s242
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发表时间:
2002-12
影响因子:
3.7
通讯作者:
A. McNeil
中科院分区:
文献类型:
--
作者:
A. McNeil
by simply using Riemann sums and Taylor’s formula, in an expeditious manner. I have used this presentation in teaching graduate students with a weak probabilistic background but a good physical intuition and strong calculus abilities and have found it quite effective and entirely satisfactory for applications. The pathwise Langevin interpretation is exploited further in Chapter 3, in which the physical interpretation of the Ornstein-Uhlenbeck process gives an admirable understanding of the classical mechanics underlying Brownian motion. I believe that this and other interesting applications of Brownian motion and diffusions to physics described in Chapter 3 are not found in standard textbooks covering stochastic differential equations. As such, this book presents a true innovation. A strong physical backing to the presentation of the topics is prevalent only in a portion of the book. Chapter 4 deals with stochastic processes that arise as stable limits of superdiffusive or subdiffusive continuous-time random walks, when either the squared space step or the time step have in nite mean. This material is presented in a more mathematically formal way than in the other chapters. Nevertheless, the treatment is not as dry as one would expect had the book been written by a pure probabilist. Despite the numerous technical calculations, the authors manage to make this dif cult topic an enjoyable read. Chapter 5, the only chapter dealing with nancial applications, provides an invaluable introduction for any person with no nancial background. It includes a short but excellent presentation of the main nancial buzz words that are the basis for understanding a mathematical nancial argumentation, along with a basic treatment of the Black–Scholes theory. Consistent with the remainder of the book, the authors have strived to make the treatment as lively as possible. However, this chapter did not live up to my expectations for several reasons. First, I was surprised to see that, with all of the effort spent in Chapters 2 and 3 on analyzing diffusion processes, the authors chose to present a partial-differential equations (PDE) method as the main tool for deriving the Black–Scholes equation. They chose to present the probabilistic method, and the risk-neutral valuation formula, only as a kind of remark. Instead, they could have used hedging ideas and Itō’s formula to derive the Black–Scholes PDE more explicitly, solving it via a Feynman–Kac formula and then using that to derive the Black–Scholes formula in a purely probabilistic way. In the context of stochastic processes, should not a presentation of mathematical nance stress stochastic calculus over PDEs? The treatment of this topic in Chapters 6 and 7 of Bjork (1998), for instance, would have been more appropriate here. For a further understanding of the power of risk-neutral valuation (whose presentation by the authors is not entirely enlightening) the book would have bene tted from a basic treatment of American options in discrete time, corresponding to a summary of the excellent Chapter 2 of Lamberton and Lapeyre (1996). My other disappointment, which I alluded to earlier, is that I was not enlightened by the physicists’ treatment of mathematical nance in this chapter in the way that I was hoping to see. This may be due to my lack of a good understanding of the portion of the chapter that deals with recent progress in what the authors call “econophysics.” One model that seems to come from econophysics is based on the truncated Lévy ight, presented earlier in the book; it aims to provide an understanding of the notorious observation that stock price volatility is stochastic. My failure to understand the physics underlying this model can be partially blamed on the authors’ lessthan-optimal presentation. The remainder of the chapter contains some interesting information on how to obtain the so-called volatility smile and on some current efforts to model nancial crashes, but it still lacks the clarity of the remainder of the book. Despite my lack of enthusiasm for the nancial part of this book, I thoroughly enjoyed the remainder of it. One particularly useful feature, especially given the authors’ intent to write a textbook, is the presence of a well-thoughtout summary at the end of each chapter. The alphabetical subject index is another good feature. What makes it more dif cult to consider this book as a textbook is the lack of exercises. As such, this book could be appropriate only for a graduate class, and may only be within the grasp of science students. It would make a good basis for a student seminar class in which each student’s task would be to present a chapter of the book, and perhaps look up some of the references generously provided at the end of each chapter. In the end, the high quality of the rst four chapters make the book well worth reading for physics students seeking an introduction to continuous-time stochastic processes, as well as anyone with a good knowledge of diffusion processes who might be interested in the physical reasons justifying the theory and its extensions to stable processes.