TRADING WITH SMALL PRICE IMPACT

An investor trades a safe and several risky assets with linear price impact to maximize expected utility from terminal wealth. In the limit for small impact costs, we explicitly determine the optimal policy and welfare, in a general Markovian setting allowing for stochastic market, cost, and preference parameters. These results shed light on the general structure of the problem at hand, and also unveil close connections to optimal execution problems and to other market frictions such as proportional and fixed transaction costs.     

Venture capital funds: Flow-performance relationship and performance persistence

This paper finds that venture capital funds that are expected to be backed by more skilled investors show no performance persistence but a significant flow-performance relationship. In contrast, funds that are expected to be backed by less skilled investors show performance predictability and have a non-significant flow-performance relationship. These results suggest that only skilled investors use all available information to adjust their capital allocation and, as a result, eliminate performance predictability as argued theoretically by Berk and Green (2004). Results also show that Kaplan and Schoar (2005) overstate the persistence in fund performance by not using an ex ante measure of the performance of earlier funds. Whether or not an ex ante measure is used, however, the persistence is largely due to unsophisticated investors. When investors are sophisticated, the performance of earlier funds, sequence and fund size do not help predict the performance of the focal fund.     

Computational aspects of robust optimized certainty equivalents and option pricing

Accounting for model uncertainty in risk management and option pricing leads to infinite‐dimensional optimization problems that are both analytically and numerically intractable. In this article, we study when this hurdle can be overcome for the so‐called optimized certainty equivalent (OCE) risk measure—including the average value‐at‐risk as a special case. First, we focus on the case where the uncertainty is modeled by a nonlinear expectation that penalizes distributions that are “far” in terms of optimal‐transport distance (e.g. Wasserstein distance) from a given baseline distribution. It turns out that the computation of the robust OCE reduces to a finite‐dimensional problem, which in some cases can even be solved explicitly. This principle also applies to the shortfall risk measure as well as for the pricing of European options. Further, we derive convex dual representations of the robust OCE for measurable claims without any assumptions on the set of distributions. Finally, we give conditions on the latter set under which the robust average value‐at‐risk is a tail risk measure.     

Pacemaker complications and costs: a nationwide economic study

Abstract

Aims: Novel leadless pacemakers (LPMs) may reduce complications and associated costs related to conventional pacemaker systems. This study sought to estimate the incidence and associated costs of traditional pacemaker complications, in those patients who were eligible for LPM implantation.

Methods: A retrospective analysis was conducted on the French National Hospital Database (PMSI), including all patients implanted with a pacemaker in France in 2012, who could have alternatively received an LPM. Complication rates and their associated costs 3 years post-implantation were estimated from the perspective of the French social security system.

Results: From a total of 65,553 patients, 11,770 (18%) met the inclusion criteria. Overall, 618 patients (5.3%) had a record of pacemaker complications during follow-up, of which 89% were related to the lead and pocket. Most common were pocket bleeding, lead- or generator-related mechanical complications, and pneumothorax. Overall, the mean cost of pacemaker complications per patient was €6,674?±?3,867 at 3 years. Specifically, €7,143?±?2,685 for pocket bleeding, €5,123?±?2,676 for pneumothorax, and €6,020?±?3,272 for mechanical complications.

Conclusions: Major complications associated with the lead and pocket of conventional pacemaker systems are still common, and these represent a significant burden to healthcare systems as they generate substantial costs.     

The Political Economy of Growth in Latin America and East Asia: Some Empirical Evidence

This article examines the historical records of poor economic performance of Latin America compared to East Asia's relative success in the 1970s and 1980s. Although both regions adopted similar postwar protective inward-oriented development strategies, their experiences and economic outcomes diverged significantly in subsequent years. Some have argued that East Asian countries outperformed Latin American ones because they implemented appropriate policies that were adaptive to changes in the global market scene. This study shows that the respective sociopolitical and institutional environment of the two regions was also an important factor contributing to their economic outcomes. A growth model augmented with policy-driven and sociopolitical variables is developed. Using data for selected countries in both regions, the results confirm the hypothesis of a negative direct (efficiency) effect of sociopolitical instability on growth, with an additional indirect (accumulation) effect through investment, irrespective of a country's location. Policies adopted by governments, particularly to control inflation and foreign indebtedness and to enhance economic freedom and human capital accumulation, appear crucial for stability. Such policies influenced economic performance through both the direct and the indirect channels. (JEL B25 , E13 , F43 , H19 , O57 )     

A costly state verification model with diversity of opinions

Summary. In simple models of borrowing and lending with ex-post asymmetric information, Gale and Hellwig (1985) and Williamson (1986) have shown that optimal debt contracts are simple debt contracts where borrowers repay a fixed interest rate whenever possible and lenders seize all the profit when borrowers default. In this note, we depart from their works by assuming that borrowers and lenders have heterogeneous beliefs, and show that simple debt contracts do not necessarily survive as optimal contracts.JEL Classification Numbers: G3, D8.     

MARKET PRICE MECHANISMS AND STACKELBERG GENERAL EQUILIBRIA: AN EXAMPLE

This paper considers Stackelberg competition in a general equilibrium framework with a productive sector. The working of market power and the configurations of strategic interactions are complexified by the presence of a leader. Two market price mechanisms are studied: one is associated with the Stackelberg–Walras equilibrium and the other is linked to the Stackelberg–Cournot equilibrium. Throughout the example of a two commodity economy, several results are obtained about equilibria mergings and about welfare comparisons.     

Multi-lender coalitions in costly state verification models

The paper analyzes the endogenous formation of a financial intermediary, modelled as a multi-lender coalition, as the trade-off between economies of scale in monitoring and a ‘cost’ associated with the partial loss of control over the investments the multi-lender coalition makes. In contrast with previous contributions (e.g., Williamson in J Monet Econ 18:159–179, 1986), the model can account for the coexistence of financial intermediation and direct lending (a non-trivial equilibrium). We prove the existence of such non-trivial equilibria and provide a complete characterization of them. In particular, the stronger the diversity of opinions, the smaller the coalition size is. I owe Pierpaolo Battigalli and Larry Samuelson a special debt for their insightful comments and encouragements. I am also grateful to the co-editor, Stephen Williamson, and an anonymous referee for insightful comments. I also like to thank Rabah Amir, Francis Bloch, Guillaume Carlier, Pascal Courty, Martin Hellwig, Bart Lipman, Jean-Marc Tallon and Anne Villamil for helpful discussions. Finally, I thank the THEMA, University Cergy-Pontoise, where part of this paper was written, for their hospitality.     

On Stackelberg competition in strategic multilateral exchange

In this paper, we consider a strategic equilibrium concept which extends Stackelberg competition to cover a general equilibrium framework. From the benchmark of strategic market games proposed by Sahi and Yao (1989), we define the notion of Stackelberg equilibrium. This concept captures strategic interactions in interrelated markets on which a finite number of leaders and followers compete on quantities. Within the framework of an example, convergence and welfare are studied. More specifically, we analyze convergence toward the competitive equilibrium and make welfare comparisons with other strategic equilibria.     

Exploring Duopoly Markets with Conjectural Variations

In this article, the authors investigate competitive firm behaviors in a two-firm environment assuming linear cost and demand functions. By introducing conjectural variations, they capture the different market structures as specific configurations of a more general model. Conjectural variations are based on the assumption that each firm believes its own strategy influences its rival's strategy. Firms derive their optimal choice from these exogenous conjectures, under the form of a conjectural best-response function. The authors’ approach fully encompasses the standard measures of market power (the Lerner Index) and concentration (the Herfindahl Index), both depending on the conjectural variations. They finally represent, analytically and graphically, the equilibrium strategies and the associated indexes in a unified framework for any level of competition, ranging from perfect competition to collusion.