Optimal Portfolio Choice under Heterogeneous Beliefs

This paper analyzes how an investor who is convinced that he can``beat the market' should behave when the equilibrium priceprocess is endogenous. The investor's optimal portfolio is shownto consist of three components: (1) a tangency portfolio, (2) ahedge portfolio against changes in the market's valuation ofsecurities, and (3) a hedging position against changes in thedivergence between the investor's and the market's beliefs. Thesign and magnitude of this third component will depend on investorpreferences and on the divergence in the investor's and themarket's quality of information. A numerical example illustratesthat the effect of heterogeneous beliefs on optimal portfolioallocations can be significant.     

The ‘Wild Cards’ of European futures: Planning for discontinuities?

The use of Wild Cards has been extensively developed in the corporate world, particularly by companies dealing with strategic commodities in global markets, i.e., the nexus between warfare, oil, and energy use. One of the purposes of Wild Cards is to test the ability of a system - usually a large organisation - to react to unforeseen but high-impact events. The work presented in this article was undertaken in the context of the project on ‘Spatial Scenarios’ for the European Spatial Planning Observation Network (ESPON) Programme. In this project, four Wild Cards were introduced: “an era of energy scarcity”, “the demise of Europe's social security system”, “the gulf stream stops”, and “the dollar goes down the drain”. These Wild Cards were introduced to investigate how external events may have asymmetric impacts across the European territory, to include some reflections on themes that were not included in the integrated scenarios, and to raise awareness of the fact that today's policy choices have to be evaluated not only in the light of current policy goals but also in the light of possible, sometimes dramatic, future events. In this way the Wild Cards helped to highlight the potential impact of external events on the territorial development of Europe and their particular impact on the internal disparities between the regions.     

DATA‐DRIVEN DRAFTING: APPLYING ECONOMETRICS TO EMPLOY QUARTERBACKS

We show that firms can employ data‐driven methods to improve their hiring decisions. Specifically, we use data available to National Football League (NFL) teams prior to the NFL draft to estimate econometric models that predict the future performance of drafted quarterbacks. As our methods are replicable, stakeholders can use them to improve the draft's efficiency and help it accomplish its mission to promote competitive balance. Furthermore, data‐driven methods such as ours can help firms avoid biases against employee characteristics that do not affect future job performance. (JEL L83)     

The impact of scale effects on the prevailing internet-based banking model in the US

Internet-based banks use a technology-intensive production process that may benefit from scale effects as they grow larger. This article analyzes whether the predominant Internet-primary bank in the USA generates technology-based economies of scale in the period 2002–2010. There is evidence of both favorable and adverse technology-based scale effects. As the leading Internet-primary bank gets larger, the financial performance gap with traditional banks shrinks while some of its critical competitive advantages wear down. The results suggest that unless the prevailing Internet-primary bank preserves the distinctive advantages of the Internet-based business model as it improves financial performance, it might end up converging with its branching competitors.     

A behavioral explanation of the value anomaly based on time-varying return reversals

We investigate the dynamics of the value anomaly in order to identify the driving forces of the anomaly. We show that the large positive value-minus-growth portfolio returns are explained by an over-reaction (under-reaction) to the positive (negative) market movements in short, specific time periods, during which the average returns of value-minus-growth portfolios are more than 2% a month. We propose an explanation based on behavioral biases: the dynamics of the value anomaly reflect the increased speed of return reversals subsequent to overreaction. Two conditions that increase the return reversals are proposed: when investors respond to public signals asymmetrically or when public signals become noisy. Our empirical results reveal that the value anomaly is explained by either one of these two channels.     

Web Services for Negotiation and Bargaining in Electronic Markets: Design Requirements, Proof-of-Concepts, and Potential Applications to e-Procurement

Information Systems researchers continue to develop Web services hoping that, in a near future, these services will be widely offered in the e-marketplace, using a Web-based protocol that is universally adopted for posting, locating and invoking available services. Posting services does not, however, necessarily lead to market transactions, and a number of brokering activities are needed to facilitate trade. These include, but are not limited to, service discovery and ranking, price negotiation and contract preparation. We propose a set of Web services that support the process of negotiation and bargaining to facilitate the matching of supply and demand of Web services. As a market broker, these web services would help (a) discover the supply/demand of web services in e-marketplaces; (b) find the most appropriate available service for a specific request; (c) facilitate services be modified if needed to satisfy user's needs; (d) arbitrate the pricing mechanism with the recourse to bargaining whenever necessary; and (e) generate a contract. As a proof of concept, we illustrate the potential use of Web services for negotiation and bargaining in e-procurement.     

A European Agenda for Smart Consumer Protection Rules for Digital Services

Digital services are increasingly important in the economy and in society in general, as they continue to shift from being a specific sector of activities to becoming the basis for the provision of most services. They offer multiple new opportunities from which consumers benefit daily, but they also raise novel questions for consumer protection.     

Exchange Rates,Employment and Labour Market Rigidity

In this paper, we study the effect of labour market rigidity on the impact of exchange rate shocks on employment. We use a panel dataset comprising 22 manufacturing sectors across 23 OECD countries. In our econometric model, the impact of exchange rate fluctuations on sectoral employment is mediated by the degree of openness and by a measure of labour market rigidity: the OECD's employment protection legislation (EPL) index. Our results suggest that greater labour market rigidity reduces the impact of exchange rate shocks on employment. This effect is statistically significant for low‐technology sectors.     

Existence of a calibrated regime switching local volatility model

By Gyöngy's theorem, a local and stochastic volatility model is calibrated to the market prices of all European call options with positive maturities and strikes if its local volatility (LV) function is equal to the ratio of the Dupire LV function over the root conditional mean square of the stochastic volatility factor given the spot value. This leads to a stochastic differential equation (SDE) nonlinear in the sense of McKean. Particle methods based on a kernel approximation of the conditional expectation, as presented in Guyon and Henry‐Labordère [Risk Magazine, 25, 92–97], provide an efficient calibration procedure even if some calibration errors may appear when the range of the stochastic volatility factor is very large. But so far, no global existence result is available for the SDE nonlinear in the sense of McKean. When the stochastic volatility factor is a jump process taking finitely many values and with jump intensities depending on the spot level, we prove existence of a solution to the associated Fokker–Planck equation under the condition that the range of the squared stochastic volatility factor is not too large. We then deduce existence to the calibrated model by extending the results in Figalli [Journal of Functional Analysis, 254(1), 109–153].