Locally lipschitz cooperative games

A locally Lipschitz cooperative generalized game is described by its coalition worth function v defined on the set [0, 1]ⁿ of generalized (or fuzzy) coalitions of n players. We assume that v is positively homogeneous and locally Lipschitz. We propose the Clarke's generalized gradient ∂v(c^N) of v at the coalition c^N=(1,…,1) of all players as a set of solutions, and we study its property. We point out that it coincides with the core when v is super–additive and to the Shapley value when v is smooth.     

Recent Advances in Structural Econometric Modeling: Dynamics, Product Positioning and Entry

In the empirical analysis of consumer markets, recent literature has begun to explore the dynamics in both consumer decisions as well as in firms' marketing policies. Other research has begun to explore the strategic aspects of product line design in a competitive environment. In both cases, structural models have given us new insights into consumer and firm behavior. For example, incorporating consumer and firm dynamics may help explain patterns in our data that are not well-captured by static models. Similarly, the strategic aspects of firm entry and product-positioning may be intrinsically linked to firm conduct and the intensity of competition in a market. Structural analysis of these consumer and firm decisions raise a number of substantial computational challenges. We discuss the computational challenges as well as specific empirical applications. The discussions are based on the session “Structural Models of Strategic Choice” from the 2004 Choice Symposium.     

‘Fit to play’: Labour market behaviour in a cohort of public-sector antiretroviral treatment patients

Given the rapid scale-up of antiretroviral treatment (ART), it is necessary to explore the impact of ART on labour force participation, employment and labour productivity. This article investigates labour market outcomes in a prospective cohort of public-sector ART clients in the Free State province of South Africa. Empirical results suggest that labour force participation increased markedly as the proportion of those too ill to work declined, becoming indistinguishable from participation rates in the general population. Unemployment rates, however, remain above those reported for the general population. ART and its health-related benefits therefore translate into increases in labour force participation, but not employment. Employment status at HIV diagnosis strongly predicts absorption in the labour force. Public-sector ART clients should be referred to vocational rehabilitation and occupational therapy programmes, and to welfare-to-work programmes, and the unskilled to adult education and training and further education and training programmes.     

Stochastic Volatility Corrections for Interest Rate Derivatives

We study simple models of short rates such as the Vasicek or CIR models, and compute corrections that come from the presence of fast mean-reverting stochastic volatility. We show how these small corrections can affect the shape of the term structure of interest rates giving a simple and efficient calibration tool. This is used to price other derivatives such as bond options. The analysis extends the asymptotic method developed for equity derivatives in Fouque, Papanicolaou, and Sircar (2000b) . The assumptions and effectiveness of the theory are tested on yield curve data.     

On Intersectoral allocations,factors substitutability and multiple long-run growth paths

Summary. This article considers a two-sector model of economic growth with “labour-augmenting” intersectoral external effects stemming from the aggregate capital stock. It is shown that equilibrium balanced growth paths with a non-trivial labour allocation scheme become available. A set of sufficient conditions for the existence of multiple equilibrium growth rays is provided and their determinacy properties are then characterised. Finally, examination of a parameterised C.E.S. economy illustrates the central role of non-unitary values for the elasticity of substitution in the multiplicity issue. Received: October 31, 2000; revised version: September 25, 2001     

Defining the Abatement Cost in Presence of Learning-by-Doing: Application to the Fuel Cell Electric Vehicle

We consider a partial equilibrium model to study the optimal phasing out of polluting goods by green goods. The unit production cost of the green goods involves convexity and learning-by-doing. The total cost for the social planner includes the private cost of production and the social cost of carbon, assumed to be exogenous and growing at the social discount rate. Under these assumptions the optimization problem can be decomposed in two questions: (i) when to launch a given schedule; (ii) at which rate the transition should be completed that is, the design of a transition schedule as such. The first question can be solved using a simple indicator interpreted as the MAC of the whole schedule, possibly non optimal. The case of hydrogen vehicle (Fuel Cell Electric Vehicles) offers an illustration of our results. Using data from the German market we show that the 2015–2050 trajectory foreseen by the industry would be consistent with a carbon price at 52€/t. The transition cost to achieve a 7.5 M car park in 2050 is estimated at 21.6 billion € that is, to JEl 4% discount rate, 115 € annually for each vehicle which would abate 2.18 tCO\(_2\) per year.     

Japan 20: The West 1 Reversing the Scorecard

The trade imbalance between Japan and its Western partners may be a source of concern, but much more serious is the even far greater investment imbalance. While Japanese direct investments have poured into the North American and European markets, American and European investments in Japan are paltry: the current ratio of investment flows is running at 20 to 1, in some cases much more, in Japan's favour. As the strategic issues for Western companies in establishing a "robust presence" in Japan are fundamental and critical, the trade and investment deficits are partly caused and further exacerbated by the "knowledge-gap" between the two. Reversing the scorecard must be the most urgent imperative for Western corporations and governments, though the effort required will be very substantial indeed.