Dynamic sorting in durable goods markets with buyer heterogeneity

In a competitive dynamic durable good market where sellers have private information about quality, I identify certain inefficiencies that arise due to heterogeneity in buyers' valuations. Even if the market induces dynamic sorting among sellers and all goods are eventually traded, inefficiency can arise because high valuation buyers buy early when low‐quality goods are sold, while high‐quality goods are allocated to low valuation buyers that buy later. This misallocation adds to the inefficiency caused by delay in trading. Under certain circumstances, high‐quality goods may never be traded as in a static market.     

Reducing Inefficiency in Public Good Provision Through Linking

We characterize the optimal mechanism for the provision of n public goods in an economy with m agents, binary valuations. The mechanism “links” the n problems together because decisions and transfers are based on the whole vector of valuations of the agents. In particular, the decision on whether or not to provide a public good depends not only on the valuations of the agents for that good but, in some cases, also on the valuations for the other goods reported by the low‐valuation agents. For the two‐agent case, we show that the mechanism is asymptotically efficient and we provide an example that compares its relative efficiency with optimal separate provision and with another asymptotically efficient mechanism in the literature.     

Sequential decisions with several agents

Summary. We consider k agents who have different subjective probabilities and are utility maximizers. A planner, who knows the beliefs of the agents, maximizes the social expected utility, which is increasing and symmetric in the utilities of the agents. She does that by optimally stopping the flow of information released to the agents. The explicit form of the optimal stopping time is given. Received: October 23, 1995; revised version: June 25, 1997     

k-Price Auctions

In this paper we analyze the equilibria structure of k-price auctions, k ≥ 3, under the independent-private-value assumption. We discuss agents with an arbitrary attitude toward risk. That is, agents may be risk averse or risk seeking, or they may have an alternating attitude toward risk. We provide a characterization of a continuous symmetric equilibrium, prove that there exists at most one such equilibrium, and show that every such equilibrium is differentiable and increasing. We also show some additional general properties of the equilibrium strategies in these auctions. Journal of Economic Literature Classification Numbers: C72, C73, D83.     

Improving market timing of time series momentum in the Chinese stock market

ABSTRACT

This paper is the first study to present firm-level evidence that the time-series momentum (TSMOM) strategies with look-back-period k of 10 to 200 days outperform the buy-and-hold strategy (BH) on individual stocks in the Chinese stock market. We document that the optimal k* generating the best performance is different across assets and varies over time. We hence propose a model to predict the asset-specific and time-dependent k*, and examine the performance of the TSMOM strategies with the predicted k*. Our analysis shows that using the time-varying predicted k* substantially improves the predictability of the TSMOM strategies. Our new model and findings shed the light on trading strategy for both academia and applied investment practitioners.     

Make a guess: a robust mechanism for King Solomon’s dilemma

We introduce endogenous fees for participating in second-price auction which we use for a two-stage mechanism to solve King Solomon’s dilemma. They are positive for all agents. They are nonetheless shown to maintain the agents’ incentives for truthful bidding and guarantee participation by the highest-value agent. This feature of the endogenous fees is powerful enough for the efficient outcome to uniquely result from one round elimination of weakly dominated strategies, followed by at most four rounds of iterative elimination of strictly dominated stage-strategies. We provide an extension to cases with n agents and k identical prizes. We thank Gary Charness, Harrison Cheng, Jeffrey Ely, Rod Garratt, Mamoru Kaneko, Xiao Luo, Albert Ma, and Steven Morris for helpful discussions. We also thank an anonymous referee for comments that have helped to improve the paper.     

Aggregation of multiple prior opinions

Experts are asked to provide their advice in a situation of uncertainty. They adopt the decision maker?s utility function, but each has a potentially different set of prior probabilities, and so does the decision maker. The decision maker and the experts maximize the minimal expected utility with respect to their sets of priors. We show that a natural Pareto condition is equivalent to the existence of a set Λ of probability vectors over the experts, interpreted as possible allocations of weights to the experts, such that (i) the decision maker?s set of priors is precisely all the weighted-averages of priors, where an expert?s prior is taken from her set and the weight vector is taken from Λ; (ii) the decision maker?s valuation of an act is the minimal weighted valuation, over all weight vectors in Λ, of the experts? valuations.     

Information structures in optimal auctions

A seller wishes to sell an object to one of multiple bidders. The valuations of the bidders are privately known. We consider the joint design problem in which the seller can decide the accuracy by which bidders learn their valuation and to whom to sell at what price. We establish that optimal information structures in an optimal auction exhibit a number of properties: (i) information structures can be represented by monotone partitions, (ii) the cardinality of each partition is finite, (iii) the partitions are asymmetric across agents. We show that an optimal information structure exists.     

On the Effect of Skewness and Kurtosis Misspecification on the Hedging Error

Using a result in Angelini and Herzel (2009a) , we measure, in terms of variance, the cost of hedging a contingent claim when the hedging portfolio is re‐balanced at a discrete set of dates. We analyse the dependence of the variance of the hedging error on the skewness and kurtosis as modeled by a Normal Inverse Gaussian model. We consider two types of strategies, the standard Black–Scholes Delta strategy and the locally variance‐optimal strategy, and we perform some robustness tests. In particular, we investigate the effect of different types of model misspecification on the performance of the hedging, like that of hedging without taking skewness into account. Computations are performed using a Fast Fourier Transform approach.     

Fair imposition

We introduce a new mechanism-design problem called fair imposition. In this setting a center wishes to fairly allocate tasks among a set of agents whose cost structures are known only to them, and thus will not reveal their true costs without appropriate incentives. The center, with the power to impose arbitrary tasks and payments on the agents, has the additional goal that his net payment to these agents is never positive (or, that it is tightly bounded if a loss is unavoidable). We consider two different notions of fairness that the center may wish to achieve. The central notion, which we call k-fairness, is in the spirit of max-min fairness. We present both positive results (in the form of concrete mechanisms) and negative results (in the form of impossibility theorems) concerning these criteria. We also briefly discuss an alternative, more traditional interpretation of our setting and results, in the context of auctions.     

Why Do the Rich Save More? A Theory and Australian Evidence*

We provide a theory to explain the existence of inequality in an economy where agents have identical preferences and have access to the same production technology. Agents consume a ‘health’ good which determines their subjective discount factor. Depending on initial distribution of capital the economy gets separated into different permanent‐income groups. This leads to a testable hypothesis: ‘The rich save a larger proportion of their permanent‐income’. We test this implication for savings behaviour in Australia. We find that even after controlling for lifecycle and health characteristics, higher permanent income is positively related with higher savings rates and better saving habits.     

Profiteering from the Dot‐Com Bubble,Subprime Crisis and Asian Financial Crisis

The paper explores the characteristics associated with the formation of bubbles that occurred in the Hong Kong stock market in 1997 and 2007, as well as the 2000 dot‐com bubble of Nasdaq. It examines the profitability of technical analysis (TA) strategies generating buy and sell signals, with and without our proposed trading rules. The empirical results show that, by applying long and short strategies during the bubble formation and a short strategy after the bubble burst, it not only produces returns that are significantly greater than buy‐and‐hold strategies, but also produces greater wealth compared with TA strategies without trading rules. We conclude that these bubble detection signals help investors generate greater wealth from applying appropriate long and short moving average (MA) strategies.     

STRATEGIC CANDIDACY AND SINGLE‐PEAKEDNESS*

In elections, the voting outcomes are affected by strategic entries of candidates. We study a class of voting rules immune to strategic candidacy. Dutta et al. (2001 ) show that such rules satisfying unanimity are dictatorial if all orderings of candidates are admissible for voters’ preferences. When voters’ preferences are single‐peaked over a political spectrum, there exist non‐dictatorial rules immune to strategic candidacy. An example is the rule selecting the m‐th peak from the left among the peaks of voters’ preferences, where m is any natural number no more than the number of voters. We show that immunity from strategic candidacy with basic axioms fully characterizes the family of the m‐th leftmost peak rules.     

Completing Incomplete Revealed Preference Under Limited Attention

This paper discusses how to improve the identification of the preference of a decision‐maker (DM) with limited attention proposed by Masatlioglu, Nakajima and Ozbay (2012). in “Revealed Attention”. Their identification method relies on choice reversals so the obtained revealed preference is often incomplete. We propose three approaches to address this problem. The first one is accommodating a model‐free approach, which respects the DM's choice in making a welfare analysis, as long as it does not contradict the revealed preference of Masatlioglu et al. The second approach incorporates the DM's exogenously obtained attention/inattention information into the model of Masatlioglu et al. The third approach is to take framings that influence the DM's attention into effect for the identification.     

Influence Of Over‐ And Underconfidence On A Marriage Market*

This paper examines misconfidence (over‐ or underconfidence) and marriage proposal strategies in a two‐sided search model with non‐transferable utility. Single agents are vertically heterogeneous—there exists a ranking of marital charm (types). It is shown that there are two externalities to over‐ or underconfident behaviour: someone's over‐ or underconfidence affects: (i) the duration of search for others who directly meet over‐ or underconfident agents; and (ii) the marriage decision of others who directly or indirectly meet over‐ or underconfident agents. Furthermore, these externalities prevent the lowest‐type agents from marrying in an equilibrium.     

When is multidimensional screening a convex program?

A principal wishes to transact business with a multidimensional distribution of agents whose preferences are known only in the aggregate. Assuming a twist (= generalized Spence-Mirrlees single-crossing) hypothesis, quasi-linear utilities, and that agents can choose only pure strategies, we identify a structural condition on the value b(x,y) of product type y to agent type x — and on the principal?s costs c(y) — which is necessary and sufficient for reducing the profit maximization problem faced by the principal to a convex program. This is a key step toward making the principal?s problem theoretically and computationally tractable; in particular, it allows us to derive uniqueness and stability of the principal?s optimal strategy — and similarly of the strategy maximizing the expected welfare of the agents when the principal?s profitability is constrained. We call this condition non-negative cross-curvature: it is also (i) necessary and sufficient to guarantee convexity of the set of b-convex functions, (ii) invariant under reparametrization of agent and/or product types by diffeomorphisms, and (iii) a strengthening of Ma, Trudinger and Wang?s necessary and sufficient condition (A3w) for continuity of the correspondence between an exogenously prescribed distribution of agents and of products. We derive the persistence of economic effects such as the desirability for a monopoly to establish prices so high they effectively exclude a positive fraction of its potential customers, in nearly the full range of non-negatively cross-curved models.     

STRATEGY‐PROOF ALLOCATION OF INDIVISIBLE GOODS AMONG COUPLES

We consider the problem of allocating indivisible goods among couples. Agents in a couple share the indivisible good assigned to them. The main result is that an allocation rule is strategy‐proof, neutral and non‐bossy if and only if it is serially dictatorial. An allocation rule is serially dictatorial if there is a priority order of couples and a function that identifies who chooses in each couple, such that for all preference profiles, a good assigned to couple i is the best element according to the preference of the identified agent in couple i among the remaining goods when the couples with higher priorities have made their choice.     

A NOTE ON THE PROPERTY RIGHTS THEORY AND THE EX ANTE VALUE OF INFORMATION

This paper examines the ex ante value of information in the property rights model where the possibility exists that an investing agent can be provided with relevant information before investments are undertaken. When contracts are incomplete, from an ex ante perspective, informing the investing agent does not necessarily increase the expected surplus resulting from a relationship between two economic agents. The paper highlights the fact that the second‐best nature of the problem that arises from contractual incompleteness can ensure this.     

Investment under Uncertainty, Debt and Taxes

It is common practice in financial derivative valuation to use a discount factor based on the riskless debt rate. But, to what extent is this discount factor appropriate for cash flows emerging in capital budgeting? To answer this question, we introduce a framework for real asset valuation that considers both personal and corporate taxation. We first discuss broad circumstances under which personal taxes do not affect valuation. We show that the appropriate discount rate for equity‐financed flows in a risk‐neutral setting is an equity rate that differs from the riskless debt rate by a tax wedge due to the presence of personal taxation. We extend this result to the valuation of the interest tax shield for exogenous debt policy with default risk. Interest tax shields, which accrue at a net rate corresponding to the difference between the corporate tax rate and a tax rate related to the personal tax rates, can have either positive or negative values. We also provide an illustrative real options application of our valuation approach to the case of an option to delay investment in a project, showing that the application of Black and Scholes formula may be incorrect in presence of personal taxes.     

A NONCOOPERATIVE SHIPPING COURNOT DUOPOLY WITH LINEAR‐QUADRATIC TRANSPORT COSTS AND CIRCULAR SPACE*

The mixed strategy equilibria in a location quantity duopoly model with circular markets are investigated. We find that a continuum of equilibria exists when the transport cost function is linear. However, if costs are strictly concave or convex, most strategies fail to qualify as equilibria. For any integer n, there are nondegenerate mixed strategy equilibria in which each firm locates at n possible locations with equal probability. This result explains possible outcomes in which firms’ on‐path locations are not minimally or maximally differentiated.