On the impact of leverage constraints on asset prices and trading volume

Abstract. Researchers have used stylized facts on asset prices and trading volume in stock markets (in particular, the mean reversion of asset returns and the correlations between trading volume, price changes and price levels) to support theories where agents are not rational expected utility maximizers. This paper shows that this empirical evidence is in fact consistent with a standard infinite horizon – perfect information – expected utility economy where some agents face leverage constraints similar to those found in todays financial markets. In addition, and in sharp contrast to the theories above, we explain some qualitative differences that are observed in the price-volume relation on stock and on futures markets. We consider a continuous-time economy where agents maximize the integral of their discounted utility from consumption under both budget and leverage constraints. Building on the work by Vila and Zariphopoulou (1997), we find a closed form solution, up to a negative constant, for the equilibrium prices and demands in the region of the state space where the constraint is non-binding. We show that, at the equilibrium, stock holdings volatility as well as its ratio to stock price volatility are increasing functions of the stock price and interpret this finding in terms of the price-volume relation. We would like to thank the editor and two anonimous referees for valuable substantive comments. Our gratitude also to Franklin Allen, Kerry Back, Domenico Cuoco, Xavier Freixas, Sanford Grossman, Michel Habib, Lutz Hendricks, Richard Kihlstrom, Fernando Restoy, Mary Thomson, Jean-Luc Vila, participants to seminars at Birkbeck College, Carnegie-Mellon, Columbia, ESSEC, HEC, IAE, INSEAD, London Business School, London School of Economics, McGill, Michigan, National University of Singapore, Pompeu Fabra, North Carolina, Washington-St-Louis, Wharton, the Jornadas de Economía Financiera BBV, and the Meetings of the Society for Economic Dynamics and Control and the American Finance Association. Special thanks are due to Süleyman Basak for his enthusiastic support and many helpful suggestions. The usual disclaimer applies. We gratefully acknowledge the support of the BBV and Caja de Madrid Foundations and CREF (both authors) and of the Spanish Ministry of Education under DGICYT grant no. PB93-0388 (first author).     

Interest rate convergence, capital controls, risk premia and foreign exchange market efficiency in the EMS

This paper examines interest rate convergence between Germany and the other EMS countries. We argue that earlier tests of convergence based on cointegration are not informative, because cointegration only implies that a linear combination of interest rates is stationary. We show that a conclusive judgment about convergence can be made if interest rate differentials exhibit a trend towards zero during the period when convergence occurred, and if the cointegrating vector has unit coefficients. We then establish that convergence has taken place in the “hard” EMS period. We also attempt to identify the sources of nonstationarities in interest differentials by examining the existence of stochastic or deterministic trends in the expected rate of depreciation and in the risk premium. Finally, the possibility of market inefficiencies is discussed.     

DEALING WITH UNCERTAINTY: ROBUST RULES IN MONETARY POLICY

We argue that in seeking to insure against model uncertainty, monetary policy makers are often ready to trade ex post performance for greater certainty in the outcome. They thus look for rules that although not optimal ex post, have certain properties that qualify them as robust. We apply first, Gul's approach of ‘disappointment’ aversion to describe policy makers' aversion to uncertainty and then define the properties the notion of ‘robustness’ entails. With these two tools we then link the desirability of such robust rules to the degree of policy makers' aversion to uncertainty. We thus show that provided such robust rules exist, a larger degree of disappointment aversion leads to a greater emphasis on robustness in policy implementation.     

External wealth, the trade balance, and the real exchange rate

We examine the link between the net foreign asset position, the trade balance and the real exchange rate. In particular, we decompose the impact of a country's net foreign asset position (‘external wealth’) on its long-run real exchange rate into two mechanisms: the relation between external wealth and the trade balance; and, holding fixed other determinants, a negative relation between the trade balance and the real exchange rate. We also provide additional evidence that the relative price of nontradables is an important channel linking the trade balance and the real exchange rate.     

Linking Public Investment to Private Investment. The Case of Spanish Regions

Public investment constitutes one of the main instruments of regional policies. The existence of a direct link between infrastructure and regional income per capita is usually accepted. Literature also describes a positive effect of public investment on private capital accumulation. This paper seeks to provide new empirical evidence on this latter relationship for the case of Spanish regions over the period 1965–1997 using panel data methodology. The results show a positive effect of productive and social public investment (especially in education) on private investment. The spillover effects generated by the productive infrastructures located in other regions do not seem to encourage the private investment in neighbouring regions. Public consumption and interest rate exert a negative influence on private capital accumulation. These results are robust to changes in the econometric specification.     

Cost effectiveness of benralizumab for severe,uncontrolled oral corticosteroid–dependent asthma in Sweden

Abstract

Aim: We investigated cost effectiveness of benralizumab vs. standard of care (SOC) plus oral corticosteroids (OCS) for patients with severe, eosinophilic OCS-dependent asthma in Sweden.

Materials and methods: A three-state, cohort-based Markov model of data from three Phase III benralizumab clinical trials (ZONDA [NCT02075255], SIROCCO [NCT01928771], and CALIMA [NCT01914757]) was used to assess the incremental cost-effectiveness ratio of benralizumab vs. SOC plus OCS. Health outcomes were estimated in terms of quality-adjusted life-years (QALYs). The model included costs and disutilities associated with extrapolated OCS-related adverse events. Patients with severe asthma were defined as those receiving OCS ≥5?mg/day.

Results: Benralizumab demonstrated a cost-effectiveness ratio vs. SOC plus OCS of 2018 Swedish Kronor (SEK) 366,855 (€34,127) per QALY gained, based on increases of 1.33 QALYs and SEK 488,742 (€45,344) per patient. Benralizumab treatment costs contributed most to incremental costs. The probability of benralizumab’s being cost-effective with willingness-to-pay (WTP) thresholds between SEK 429,972 (€40,000) and SEK 752,452 (€70,000) ranged from 75% to 99%.

Limitations: Potential limitations of these analyses include the use of combined data from three different clinical trials, a one-way sensitivity analysis that did not include mortality and transition estimates, and Observational & Pragmatic Research Institute (OPRI) data from the UK as a proxy of the Swedish health care system.

Conclusions: The results of these analyses demonstrate that benralizumab has a high probability of being cost-effective compared with SOC plus OCS for a subgroup of patients with severe, eosinophilic asthma receiving regular OCS treatment and may support clinicians, payers and patients in making treatment decisions.     

Dynamic duopoly with learning through market experimentation

Summary This paper analyzes how learning behaviors can substantially modify the outcome of competition in an oligopolistic industry facing demand uncertainty. We consider the case of a symmetric duopoly game where firms have imperfect information about market demand and learn through observing the volume of their sales. The main body of the paper consists in showing how market experimentation can explain the existence ofprice-dispersion in an oligopolistic industry. We study this phenomenon and its dynamic evolution in the context of an Hotelling duopoly model; we then extend the analysis to general demand functions and toN-firm oligopolies. We discuss some implications of the public good aspect of information about market demand. We then conclude with a few comments on what happens when the value of information in the oligopolistic industry is negative.We are very grateful to Patrick Bolton for his helpful advice. We also wish to thank Richard Caves, Anthony Creane, Jean-Jacques Laffont, Andreu Mas-Colell, Eric Maskin, Jean-Charles Rochet, Margaret Slade, John Sutton, Jean Tirole, Mike Whinston and an anonymous referee.     

Strategic Environmental Standards, Wage Incomes and the Location of Polluting Firms

The purpose of this paper is tostudy how the choice of environmental standardsby governments is affected by the existence ofwage incomes when firms locations areendogenous. In developed countries labor isunionized, which allows positive wage incomesto arise. Thus, each government has incentivesto persuade firms to locate in its countrysince social welfare depends on suchincomes. But, as pollution damages theenvironment, each government will only try toattract polluting firms to thecountry, to obtain the wage incomes, whenthe valuation of environmental damage showsthat it is low.