Consumption-investment problem with transaction costs for Lévy-driven price processes

We consider an optimal control problem for a linear stochastic integro-differential equation with conic constraints on the phase variable and with the control of singular–regular type. Our setting includes consumption-investment problems for models of financial markets in the presence of proportional transaction costs, where the prices of the assets are given by a geometric Lévy process, and the investor is allowed to take short positions. We prove that the Bellman function of the problem is a viscosity solution of an HJB equation. A uniqueness theorem for the solution of the latter is established. Special attention is paid to the dynamic programming principle.     

Do Promotions Increase Store Expenditures? A Descriptive Study of Household Shopping Behavior

An important question for retailers is whether promotions induce households to increase their in-store expenditures or merely reallocate a predetermined shopping budget. Should expenditures be fixed, retailers might decrease their profitability when running promotions by displacing expenditures from high margin to lower margin products. Using household level store receipts and an extended AIDS model, we provide evidence that while household expenditures do increase with promotions, there is also a significant reallocation of expenditures among the different categories. This implies that retailers have to choose carefully which products are promoted, if promotions are to increase profits.     

Social choice and electoral competition in the general spatial model

This paper extends the theory of the core, the uncovered set, and the related undominated set to a general set of alternatives and an arbitrary measure space of voters. We investigate the properties of social preferences generated by simple games; we extend results on generic emptiness of the core; we prove the general nonemptiness of the uncovered and undominated sets; and we prove the upper hemicontinuity of these correspondences when the voters’ preferences are such that the core is nonempty and externally stable. Finally, we give conditions under which the undominated set is lower hemicontinuous.     

Self-Enforcing Labour Contracts and Macroeconomic Dynamics

To properly account for the dynamics of the key macroeconomic variables, researchers incorporate various internal propagation mechanisms in their models. In general, these mechanisms implicitly rely on the assumption of a perfect equality between the real wage and the marginal product of labour. This paper features a micro-founded model of a limited-commitment firm, and derive endogenous dynamic labour contracts that produce a different linkage between the real wage and the marginal product of labour. The risk-sharing between the entrepreneur and the worker, both faced with enforcement problems, provides a different type of propagation mechanism. I investigate the dynamic properties of this endogenous rigidity in relation to the initial bargaining power of each agent.      

Is bioenergy trade good for the environment?

We analyze the impacts of bioenergy trade on greenhouse gas emissions using a two-good, three-factor model. Bioenergy is an agricultural good used as a substitute for fossil fuels in industry. Governments tax domestic pollution without international coordination. We assume that northern countries have higher labor productivity than southern ones and that agriculture is less pollution intensive than industry (after taxation). We show that whereas southern countries impose a lower tax rate than northern ones, they do not necessary have a competitive advantage in industry, and that compared to autarky, trade liberalization either increases or decreases worldwide emissions depending on regional comparative advantages.     

Accounting for Employee Stock Options: What Can We Learn from the Market's Perceptions?

The scope of this is paper is to provide new empirical evidence on the value relevance of employee stock options (ESOs) in Europe. We show, empirically, that the market participants when pricing a firm's equity place approximately the same valuation weights on the ESO‐deferred compensation expense (the so called “ESO asset”) and the compensation option liability (the so called “ESO liability”). Our empirical findings support the theoretical work of Ohlson and Penman who suggest that the deferred compensation expense be treated as a contra‐liability. The second contribution of our work rests on the nature of the ESO expense. We show that the distinction between persistent and non‐persistent ESO expenses is of critical importance for the market participants. Accordingly, an improved accounting disclosure should assist the investors in assessing the long‐term goals of the ESO plans at the firm level.     

Recognizing the benefits of diversity: When and how does diversity increase group performance?

Diversity does not only bring positive consequences. It has often been recognized that heterogeneity in teams can reduce intra-group cohesiveness, and that it can lead to conflicts and misunderstandings which, in turn, can lower employee satisfaction, citizenship behaviors and increase turnover. On the other hand, there is also evidence for performance-increasing effects of diversity because it can improve creativity and innovation through the team members' greater variety of perspectives. Little is known, however, about the conditions and the psychological mechanisms required for increasing group performance under diverse settings. Answers to research questions such as how and when diversity influences performance at work are still limited. The purpose of the paper is to provide theoretical answers to these questions by proposing a model of managing diversity which draws on social psychology theories. The model brings a new perspective by identifying the process of learning from one another's identity within a group. This process underlies two different levels of mechanisms (individual and group level). The model proposes that when these social psychological mechanisms are activated, diversity will lead to an increase in group performance. The model also suggests that collective identity is salient and when psychological safety climate are the psychological conditions that activate these mechanisms.     

IMF’s assistance: Devil’s kiss or guardian angel?

This paper contributes to the debate on the efficacy of IMF’s catalytic finance in preventing financial crises. Extending Morris and Shin (J Int Econ 70: 161–177, 2006), we consider that the IMF’s intervention policy usually exerts a signaling effect on private creditors and that several interventions in sequence may be necessary to avert an impending crisis. Without the IMF’s signaling ability, our results state that repeated intervention is required to bail out a country, whereby additional assistance may induce moral hazard on the debtor side. Contrarily, if the IMF exerts a strong signaling effect, one single intervention suffices to avoid liquidity crises.