Controlling portfolio skewness and kurtosis without directly optimizing third and fourth moments

In spite of their importance, third or higher moments of portfolio returns are often neglected in portfolio construction problems due to the computational difficulties associated with them. In this paper, we propose a new robust mean–variance approach that can control portfolio skewness and kurtosis without imposing higher moment terms. The key idea is that, if the uncertainty sets are properly constructed, robust portfolios based on the worst-case approach within the mean–variance setting favor skewness and penalize kurtosis.     

A COMPARISON OF CONDITIONAL AND UNCONDITIONAL APPROACHES IN VALUE‐AT‐RISK ESTIMATION*

In this paper, we attempt to find the most important factor causing the differences in the performance of Value‐at‐Risk (VaR) estimation by comparing the performances of conditional and unconditional approaches. For each approach, we use various methods and models with different degrees of flexibility in their distributions including S_U‐normal distribution, which is one of the most flexible distribution functions. Our empirical results underscore the importance of the flexibility‐of‐distribution function in VaR estimation models. Even though it seems to be unclear which approach is better between conditional and unconditional approaches, it seems to be clear that the more flexible distribution we use, the better the performance, regardless of which approach we use.     

Portfolio choice and pricing in illiquid markets

This paper studies portfolio choice and pricing in markets in which immediate trading may be impossible. It departs from the literature by removing restrictions on asset holdings, and finds that optimal positions depend significantly and naturally on liquidity: When expected future liquidity is high, agents take more extreme positions, given that they do not have to hold those positions for long when they become undesirable. Consequently, larger trades should be observed in markets with more frequent trading. Liquidity need not affect the price significantly, however, because liquidity has offsetting impacts on different agents' demands. This result highlights the importance of unrestricted portfolio choice. The paper draws parallels with the transaction-cost literature and clarifies the relationship between the price level and the realized trading frequency in this literature.     

Non-addictive habits: optimal consumption-portfolio policies

We formulate a model of preferences with non-addictive habits, where consumption is required to be non-negative at all times, but can fall below a “standard of living” index that aggregates past consumption. We study the consumption-portfolio problem taking account of the non-negativity constraint on consumption, and provide a constructive proof for the existence of an optimal policy on a finite time-horizon [0,T]. We show that the consumption constraint binds up to an endogenous stopping time τ∗∈[0,T], after which it remains slack until T. A decomposition of constrained consumption involving an Asian average-strike capped call-option is demonstrated.     

Core tâtonnement

Two discrete time tâtonnement processes—one featuring successive tâtonnement, the other featuring simultaneous tâtonnement—for the core of coalitional games with transferable utility are introduced. For totally balanced games, the successive core tâtonnement process corresponds to the standard simultaneous price tâtonnement process of competitive equilibrium theory via the Shapley-Shubik (market game-direct market) correspondence. The simultaneous core tâtonnement process is based entirely on the intuition behind the definition of the core for games with transferable utility, and it does not correspond to any evident competitive equilibrium tâtonnement process. Both processes are proven to be globally stable. The two processes offer easily implementable algorithms for approximately computing core points.     

A CLASS OF PERFORMANCE‐BASED SUBSIDY RULES*

We consider a benchmark static incentive scheme, i.e. a per unit subsidy, that induces a monopoly to produce a target output level. We show that the same output level can be achieved by a continuum of dynamic subsidy rules based on a performance indicator. The rules require only local information. The present value of the subsidies paid is smaller than the amount paid under the static subsidy. Each of the dynamic subsidy rules results at each moment in a lower per unit subsidy than the static subsidy. The subsidy rate depends on a state variable that reflects the monopolist's performance history.     

The Displacement Effect of Labour‐Market Programs: MONASH Analysis*

A key question concerning labour‐market programs is the extent to which they generate jobs for their target group at the expense of others. This effect is measured by displacement percentages. We describe a version of the MONASH model designed to quantify the effects of labour‐market programs. Our simulation results suggest that: (i) labour‐market programs can generate significant long‐run increases in employment; (ii) displacement percentages depend on how a labour‐market program affects the income trade‐off faced by target and non‐target groups between work and non‐work; and (iii) displacement percentages are larger in the short run than in the long run.     

Illiquidity, position limits, and optimal investment for mutual funds

We study the optimal trading strategy of mutual funds that face both position limits and differential illiquidity. We provide explicit characterization of the optimal trading strategy and conduct an extensive analytical and numerical analysis of the optimal trading strategy. We show that the optimal trading boundaries are increasing in both the lower and the upper position limits. We find that position limits can affect current trading strategy even when they are not currently binding and other seemingly intuitive trading strategies can be costly. We also examine the optimal choice of position limits.     

THE SECOND‐PRICE AUCTION SOLVES KING SOLOMON'S DILEMMA*

The planner wants to give k identical, indivisible objects to the top k valuation agents at zero costs. Each agent knows her own valuation of the object and whether it is among the top k. Modify the (k+ 1)st‐price sealed‐bid auction by introducing a small participation fee and the option not to participate in it. This simple mechanism implements the desired outcome in iteratively undominated strategies. Moreover, no pair of agents can profitably deviate from the equilibrium by coordinating their strategies or bribing each other.     

A structural dynamic microsimulation model of household savings and labour supply

A structural model of the household is described that represents current best-practice in the analysis of savings and labour supply responses to the policy environment. Care has been taken in specifying the model so that it represents an appropriate basis for the analysis of incentive effects to policy change, and for exploring the empirical support for alternative structural assumptions. Matching the model to survey data for the UK reveals some interesting puzzles in relation to the timing of retirement.     

A new estimator for trade costs and its small sample properties

This paper discusses the estimation of parameters of a traditional transportation model, as it is typically present in so-called Takayama–Judge type spatial price equilibrium models. In contrast to previously used estimation methods, observations of regional prices as well as of trade costs are used in a direct estimation of the first order conditions. The proposed method uses bi-level programming techniques to minimize a weighted least squares criterion under the restriction that the estimated parameters satisfy the Kuhn–Tucker conditions for an optimal solution of the transport model. A penalty function and a smooth reformulation are used to iteratively approximate the complementary slackness conditions. Monte-Carlo simulations are used to trace out some properties of the estimator and compare it with a traditional calibration method. The analysis shows that the proposed technique estimates prices as well as trade costs more precisely than the traditional calibration method. It is suggested to apply the same method to a range of linear and quadratic models.     

INTERNATIONAL AND INTRA‐NATIONAL TRADE: A CONTINUUM APPROACH*

We build up a Ricardian trade model with multiple regions within a nation and examine how international trade determines interregional patterns of production and specialization. We show that the degree of interregional concentration of economic activities moves in different directions in two trading nations. The role of “absolute advantage” becomes crucial in dictating the course of income disparity across regions. We discuss cases with varying degrees of labour mobility and reconfirm the result on post‐trade interregional concentration and dispersion. Later we explore the impact of “scale factor” in this model and show how principle of comparative advantage and economies of scale interact to determine the pattern of specialization and volume of trade.     

Default and liquidity regimes in the bond market during the 2002–2012 period

Using a real‐time random regime shift technique, we identify and discuss two different regimes in the dynamics of credit spreads during 2002–2012: a liquidity regime and a default regime. Both regimes contribute to the patterns observed in credit spreads. The liquidity regime seems to explain the predictive power of credit risk on the 2007–2009 NBER recession, whereas the default regime drives the persistence of credit spreads over the same recession. Our results complement the recent dynamic structural models as well as monetary and credit supply effects models by empirically supporting two important patterns in credit spreads: the persistence and the predictive ability toward economic downturns.     

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).     

Willingness‐to‐pay for parallel private health insurance: evidence from a laboratory experiment

Abstract Debate over the effects of public versus private health care finance persists in both academic and policy circles. This paper presents the results of a revealed preference laboratory experiment that tests how characteristics of the public health system affect a subject's willingness‐to‐pay (WTP) for parallel private health insurance. Consistent with the theoretical predictions of Cuff et al. (2010), subjects’ average WTP is lower and the size of the private insurance sector smaller when the public system allocates health care based on need rather than randomly and when the probability of receiving health care from the public system is high.     

Consumption, Wealth, and Indebtedness in the Context of Uncertainty: The Consumption Function Meets Portfolio Theory

The objective of this paper is to provide a sound theoretical framework for the empirical analysis of consumer indebtedness, by integrating Portfolio theory with the Life-Cycle hypothesis (LCH) model of consumption. Modern versions of this LCH theory almost always assume that utility is additive over time, but in this study, the multiplicative Cobb–Douglas function is used. The new synthesis also explains the stochastic properties of consumption more fully and clearly than previous studies, in particular the uncertainty arising from rates of return on risky assets. The new theory will also help to improve the explanation of the surprise changes in consumption because these sources of risk are incorporated explicitly into the analysis.     

TURNPIKE PROPERTIES OF A MONEY‐IN‐THE‐UTILITY‐FUNCTION MODEL*

This study establishes the global stability of a long‐run stationary state in a money‐in‐the‐utility‐function model. The major finding is that the constant money supply rule results in a stable allocation and price system if consumers discount their future utilities sufficiently weakly. Nominal and real interest rates will be in the neighbourhood of the inverse of the consumers’ discount factor β^‐1.     

Tangency capacity notions based upon the profit and cost functions: A non-parametric approach and a general comparison

This contribution provides a way to define and compute a tangency notion of economic capacity based upon the relation between the various directional distance functions and the profit and cost functions using non-parametric technologies. A new result relating profit and cost function-based tangency capacity notions is established.