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.     

Tests for Multiple Breaks in the Trend with Stationary or Integrated Shocks

In this paper, we propose new tests of the presence of multiple breaks in the trend of a univariate time‐series where the number and dates of the breaks are unknown and that are valid in the presence of stationary or unit root shocks. These tests can also be used to sequentially estimate the number of breaks. The behaviour of the proposed tests is studied through Monte Carlo experiments.     

An evolutionary game theory approach to the dynamics of the labour market: A formal and informal perspective

A stylized fact of the labour market in developing countries is that it is highly segmented in informality. One of the main factors that induce workers and firms into informality is an excessive regulatory system that makes formal economy little attractive. This study aims to analyze the dynamics of workers and firms’ entrance and withdrawal of the formal and informal economy, assessing the impact of taxes by using an evolutionary game theory approach in which economic agents decide for one these markets according to the expected pay-off. Moreover, the optimal relation between regulatory and enforcement action by the government is evaluated.     

On-the-job training and rigidity of employment protection in the developing world: Evidence from differential enforcement

This paper analyzes the causal effect between strict employment protection regulations and the firm incentive to invest in job training of their employees. We explore a large firm level data set across several developing countries and assume that the rigidity of labor regulations affects more the investment decision of firms that faces a rigid enforcement of labor regulations. Our findings show that differences across countries in the enforcement of more rigid employment protection regulation are associated with very small differences in the investment in job training across firms. This finding is robust across several specifications and samples.     

Pricing real options under the constant elasticity of variance diffusion

Much of the work on real options assumes that the underlying state variable follows a geometric Brownian motion with constant volatility. This paper uses a more general assumption for the state variable process that better captures the empirical regularities found in commodity markets. We use the constant elasticity of variance diffusion, where volatility is a function of underlying asset prices, and we provide analytic solutions for perpetual American options. We show that a firm that uses the standard lognormal assumption is exposed to significant errors of analysis, which may lead to nonoptimal investment and disinvestment decisions. © 2010 Wiley Periodicals, Inc. Jrl Fut Mark 31:230–250, 2011     

Interest Rate Derivatives in a Duffie and Kan Model with Stochastic Volatility: An Arrow-Debreu Pricing Approach

Simple analytical pricing formulae have been derived, by different authors and for several derivatives, under the Gaussian Langetieg (1980) model. The purpose of this paper is to use such exact Gaussian solutions in order to obtain approximate analytical pricing formulas under the most general stochastic volatility specification of the Duffie and Kan (1996) model. Using Gaussian Arrow-Debreu state prices, first order stochastic volatility approximate pricing solutions will be derived only involving one integral with respect to the time-to-maturity of the contingent claim under valuation. Such approximations will be shown to be much faster than the existing exact numerical solutions, as well as accurate.     

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.     

Still Searching (Systematically)<Superscript>1</Superscript> for Entrepreneurial Discoveries

We examine how entrepreneurs can search deliberately for discoveries. We use consideration sets to impose constraints on how and where they search. A consideration set is a promising set of information channels, which entrepreneurs can select and search based on prior knowledge. To decide how to search the channels in a consideration set, we apply existing mathematical formalism to illustrate a maximal search sequence. Because there is some probability that a search sequence could continue indefinitely, we determine stopping rules. We argue that entrepreneurial search is more feasible within a consideration set than it is in the rest of the world.     

Your loyalty program is betraying you

Even as loyalty programs are launched left and right, many are being scuttled. How can that be? These days, everyone knows that an old customer retained is worth more than a new customer won. What is so hard about making a simple loyalty program work? Quite a lot, the authors say. The biggest challenges include clarifying business goals, engineering the reward structure, and creating incentives powerful enough to change buying behavior but not so generous that they erode margins. Additionally, companies have to sort out the puzzles of consumer psychology, which can result, for example, in two rewards of equal economic value inspiring very different levels of purchasing. In their research, the authors have discovered patterns in what the successful loyalty programs get right and in how the others fail. Together, their findings constitute a tool kit for designing something rare indeed: a program that won't do you wrong. To begin with, it's important to know exactly what a loyalty program can do. It can keep customers from defecting, induce them to consolidate certain purchases with one seller (in other words, win a greater share of wallet), prompt customers to make additional purchases, yield insight into their behavior and preferences, and turn a profit. A program can meet these objectives in several ways--for instance, by offering rewards (points, say, or frequent-flier miles) divisible enough to provide many redemption opportunities but not so divisible that they fail to lock in customers. Companies striving to generate customer loyalty should avoid five common mistakes: Don't create a new commodity, which can result in price wars and other tit-for-tat competitive moves; don't cater to the disloyal by making rewards easy for just anyone to reap; don't reward purchasing volume over profitability; don't give away the store; and, finally, don't promise what can't be delivered.     

Share the Fame or Share the Blame? The Reputational Implications of Partnerships

We use an adverse selection model to study the dynamics of firms' reputations when firms implement joint projects. We show that in the case of joint projects a firm's reputation does not necessarily increase following a success and does not necessarily decrease following a failure. We also study how reputation considerations affect firms' decisions to participate in joint projects. We show that a high‐reputation partner is not necessarily preferable to a low‐reputation partner and, when implementation of the joint project by a single firm is possible, a high‐quality partner may not be preferable to a low‐quality partner.