Optional decomposition and Lagrange multipliers

Let be the set of equivalent martingale measures for a given process , and let be a process which is a local supermartingale with respect to any measure in . The optional decomposition theorem for states that there exists a predictable integrand such that the difference is a decreasing process. In this paper we give a new proof which uses techniques from stochastic calculus rather than functional analysis, and which removes any boundedness assumption.     

A note on pricing interest rate derivatives when forward LIBOR rates are lognormal

We derive the closed form pricing formulae for contracts written on zero coupon bonds for the lognormal forward LIBOR rates. The method is purely probabilistic in contrast with the earlier results obtained by Miltersen et al. (1997).     

Which improves welfare more: A nominal or an indexed bond?

Summary. Economists have long argued that loan contracts should be indexed to remove the risks arising from fluctuations in the purchasing power of money: indexation however while eliminating one risk, substitutes another, arising from fluctuations in relative prices of goods. We present a theoretical framework which permits the relative merits of a nominal versus an indexed bond to be assessed in a general equilibrium setting. Received: July 31, 1995; revised version August 7, 1996     

Utility representation of continuous preferences

Summary.  By generalising the Arrow-Hahn approach, we give new conditions under which a preference relation on a metric space can be represented by a continuous utility function. Received: December 11, 1995; revised version July 29, 1996     

Ranking investment projects

Summary. This paper describes conditions under which one investment project dominates a second project in terms of net present value, irrespective of the choice of the discount rate. The resulting partial ordering of projects has certain similarities to stochastic dominance. However, the structure of the net present value function leads to characterizations that are quite specific to this context. Our theorems use Bernstein's (1915) innovative results on the representation and approximation of polynomials, as well as other general results from the theory of equations, to characterize the partial ordering. We also show how the ranking is altered when the range of discount rates is limited or the rate varies period by period. Received: January 5, 2002; revised version: October 29, 2002 RID="*" ID="*" We thank Robert Driskill, Andrea Maneschi, Roy Radner, and participants of seminars at NYU, Notre Dame, Purdue, and Washington University for helpful comments. The present version of the paper has benefited from comments by a referee and the editor. Foster is grateful for support from the John D. and Catherine T. MacArthur Foundation through its network on Inequality and Poverty in Broader Perspective. Correspondence to: T. Mitra     

Robustness of sunspot equilibria

Summary. A sunspot equilibrium (SSE) is based on some extrinsic randomizing device (RD). We analyze the robustness of SSE. (1) We say that an SSE allocation is robust to refinements if it is also an SSE allocation based on any refinement of its RD. (2) We introduce two core concepts for analyzing the robustness of SSE in the face of cooperative-coalition formation. In the first, the blocking allocations are based on the RD that defines the SSE. In the second (stronger) core concept, coalitions select their own RDs. For the convex economy with restricted market participation, SSE allocations are robust under each of the definitions and the cores converge on replication of the economy to the set of SSE allocations. For the economy with an indivisible good, SSE allocations are not always robust. We provide examples of each of the following: (i) an SSE allocation that is not robust to refinement, (ii) an SSE allocation that is in neither core, (iii) an SSE allocation that is in the first core, but not in the second, and (iv) a core that does not converge upon replication to the set of SSE allocations. Received: July 31, 1995; revised version August 30, 1996     

A pitchfork bifurcation in the tatonnement process★

Summary . This note extends the example of Gale (1963) by considering the continuous time tatonnement process for a class of two agent, two commodity exchange economies, parametrized by a number μ∈(0,1). We demonstrate that as the parameter passes a threshold value μ^* the unique, globally stable competitive equilibrium loses local stability while two new locally stable equilibria appear. Intuitively, as μ increases the income effect become increasingly more important relative to substitution effect, and eventually overwhelms the latter. As the parameter μ approaches 1, the economy tends to the example considered by Gale, as does the limiting behavior of the tatonnement. Received: February 28, 1996; revised version August 5, 1996     

基于ABC法下的作业成本管理相关问题

基于成本动因分析的作业成本会计和基于作业成本信息的作业成本管理是目前管理会计界所探讨的热点问题之一，本文从成本动因分析入手，阐述了成本动因的基本理念与选择成本动因应考虑的基本因素，提出了基于成本动因而建立的ABC方法以及如何基于ABC法下的信息进行作业成本管理。     

控制论视角的利益相关者分类

对利益相关者进行分类是整个利益相关者理论研究的热点,也是近年来一直困扰公司治理学界的难点。文章以控制论的基本逻辑提出利益相关者的分类应以其在公司治理中的地位为切入点,将利益相关者分为主导型利益相关者、接受型利益相关者和间接型利益相关者,并进一步探讨了这三种利益相关者之间的相对关系。     

A family of inverse demand systems and choice of functional form

Barten's (1992) analysis of choice of functional form for quantity-dependent demand systems is extended to price-dependent or inverse demand systems. Alternative inverse demand systems combining the features of the Rotterdam inverse demand and almost ideal inverse demand systems are examined. Choice of functional form is made through a synthetic model which under appropriate restrictions yields the different inverse demand systems. The synthetic model itself can also be considered a more flexible specification.