Restricted houseswapping games

Restricted houseswapping games (RHGs) are a generalization of ‘one-sided matching games’, in which we specify a class II* of ‘allowable’ simple trading cycles. The cores of such games may be empty. Given II*, all possible closed RHGs have non-empty cores of II* is ‘strongly balanced’. Examples include the one-sided matching markets (^{Shapley and Scarf. Journal of Mathematical Economics 1974. 1. 23–37}. ^{Tijs et al., OR Spektrum 1984, 6, 119–123}; ^{Quinzii, International Journal of Game Theory 1984, 13, 41–60}) and the two-sided matching markets (^{Gale and Shapley. American Mathematical Monthly 1962. 69, 9–16}; ^{Shapley and Shubik, International Journal of Game Theory 1972, 1, 111–130}: and ^{Demange and Gale Econometrica 1985, 53, 873–888}).We then consider the subclass of RHGs in which there is no transferable resource. In this case, a weaker condition on II*, called ‘weak balancedness’, is sufficient to guarantee core non-emptiness. In addition, if II* is not weakly balanced, then there exists a preference profile such that the strict core of the resultant game is empty.Several other examples are given of II* that are (a) strongly balanced: (b) weakly balanced but not strongly balanced: and (c) not even weakly balanced.Finally, we discuss the issues of equilibrium definition, existence, and core-equilibrium allocation equivalence in RHGs.     

Farsighted house allocation

In this note we study von Neumann–Morgenstern farsightedly stable sets for Shapley and Scarf (1974) housing markets. Kawasaki (2010) shows that the set of competitive allocations coincides with the unique von Neumann–Morgenstern stable set based on a farsighted version of antisymmetric weak dominance (cf., Wako, 1999). We demonstrate that the set of competitive allocations also coincides with the unique von Neumann–Morgenstern stable set based on a farsighted version of strong dominance (cf., Roth and Postlewaite, 1977) if no individual is indifferent between his endowment and the endowment of someone else.     

Estimating the structural credit risk model when equity prices are contaminated by trading noises

The transformed-data maximum likelihood estimation (MLE) method for structural credit risk models developed by Duan [Duan, J.-C., 1994. Maximum likelihood estimation using price data of the derivative contract. Mathematical Finance 4, 155–167] is extended to account for the fact that observed equity prices may have been contaminated by trading noises. With the presence of trading noises, the likelihood function based on the observed equity prices can only be evaluated via some nonlinear filtering scheme. We devise a particle filtering algorithm that is practical for conducting the MLE estimation of the structural credit risk model of Merton [Merton, R.C., 1974. On the pricing of corporate debt: The risk structure of interest rates. Journal of Finance 29, 449–470]. We implement the method on the Dow Jones 30 firms and on 100 randomly selected firms, and find that ignoring trading noises can lead to significantly over-estimating the firm’s asset volatility. The estimated magnitude of trading noise is in line with the direction that a firm’s liquidity will predict based on three common liquidity proxies. A simulation study is then conducted to ascertain the performance of the estimation method.     

Russia’s and Kazakhstan’s agro-food sectors under liberalized agricultural trade: a case for national product differentiation

Russia is a major importer of agro-food products in the Commonwealth of Independent States (CIS), whereas Kazakhstan’s agro-food sector is more export-oriented. Based on a multi-market-model with bilateral trade, the paper investigates how a Common Agricultural Market (CAM) and World Trade Organization (WTO) accession would affect prices, quantities, and welfare on agro-food markets in both countries. Trade diversion effects are expected because of a changed tariff structure. Kazakhstan’s agro-food sector will loose price competitiveness on Russia’s markets if liberalization is too narrowly focused on import tariffs. Simulations also suggest that national product differentiation can be part of a strategy for Russian agro-food industries to cope with stronger international competition.     

Implementation in generalized matching problems

We search for (Nash) implementable solutions on a class of one-to-one matching problems which includes both the housing market (Shapley and Scarf, Journal of Mathematical Economics, 1974, 1, 23–28) and marriage problems (Gale and Shapley, American Mathematical Monthly, 1962, 69, 9–15). We show that the core correspondence is implementable. We show, furthermore, that any solution that is Pareto efficient, individually rational, and implementable is a supersolution of the core correspondence. That is, the core correspondence is the minimal solution that is Pareto efficient, individually rational, and implementable. A corollary of independent interest in the context of the housing market is that the core correspondence is the only single-valued solution that is Pareto efficient, individually rational, and implementable.     

Social dumping and relocation: is there a case for imposing a social clause?

Public opinion in Europe seems worried about the relocation of production plants toward low wage countries often accused of practicing ‘social dumping’. To reduce the incentives for relocation trade unions proposed the adoption of ‘social clauses’ protecting domestic markets from commodities produced in countries where minimal labor condition are not met. We analyze the effects of the adoption of a social clause in a vertically differentiated Bertrand duopoly. We assess how such a policy affects firms’ relocation decisions in order to be able to assess its welfare implications. We also characterize the optimal social clause policy, both under domestic welfare maximization, and from an efficiency point of view. While we show that a social clause policy cannot be dismissed on domestic (or world) welfare grounds, its case is weaker the higher is the domestic wage and the lower is the foreign wage.     

On cores and indivisibility

An economic model of trading in commodities that are inherently indivisible, like houses, is investigated from a game-theoretic point of view. The concepts of balanced game and core are developed, and a general theorem of Scarf's is applied to prove that the market in question has a nonempty core, that is, at least one outcome that no subset of traders can improve upon. A number of examples are discussed, and the final section reviews a series of other models involving indivisible commodities, with references to the literature.     

Individual investors surpass their reputation: Trading behaviour on the Polish futures market

This paper examines individual investors’ trading behaviour by testing the presence of Monday and January anomalies on the Polish futures market, where individuals are the predominant trader type. Both anomalies are well established in the literature, and they are at least partially attributed to individual investors’ trading activities. We conduct an intraday analysis of trading volume, open interest, returns, and return volatility on the futures market in Poland and find the contribution of individuals to market anomalies to be grossly overstated. Hence, individual investors’ trading on the Polish futures market surpasses the prediction by the majority of investigations for mature stock markets.     

Stochastic processes of temporary equilibria

It is the aim of the paper to study within the framework of an ‘overlapping generation model’ the evolution of temporary equilibria. At date t, there are ‘newborn’ agents and ‘old’ agents who were born in previous periods; the old agents hold cash balances (fiat money) that they carried over from the previous period. At the beginning of period t, all agents receive a random endowment of consumption goods. Then the agents exchange these endowments and money on spot markets at date t (trading in future markets is not considered). Once a temporary equilibrium is reached, the economy move to the next date. Agents who were born at date t then become old and meet agents born at period t+1.It is shown that the evolution of temporary equilibria in this model leads to analyse the ergodic properties of a certain class of Markov processes with stationary transition probability.     

Contestability of the urban land market: an event study of Hong Kong land auctions

The traditional theory of urban land markets assumes perfect contestability—the absolute freedom of market entry—that compels developers to bid up the land rent to equal the economic profit from land use. This assumption, however, is empirically untested due to the difficulties in measuring the ex ante economic profit of land acquisition. We overcome these difficulties by applying the event-study methodology to Hong Kong government land auctions. When a developer acquires a site at a price below its fair market value, the rationality of the stock market entails a positive abnormal return on the developer’s stock. Our analysis shows evidence of positive expected abnormal returns, indicating an imperfectly contestable land market. We further show that the expected abnormal return increases with the site value and the government land disposal level but decreases with the property market liquidity.     

Maternal full-time employment and overweight children: Parametric, semi-parametric, and non-parametric assessment

We use the matched mother-child data from the 2000 wave of the US National Longitudinal Survey of Youth 79 (NLSY79) to assess the impact of full-time working mothers on children’s body mass index (BMI) and the likelihood of becoming overweight. Parametric, semi-parametric and non-parametric methods are employed to correct the bias of selection on observables and unobservables. Pros and cons of various methods are discussed and specification tests are conducted. In general, we find that a mother’s full-time employment does have some impact on her children’s BMI and likelihood of becoming overweight across models and inference procedures.     

Simultaneity in the market for housing characteristics

The nature of simultaneity in the markets for housing characteristics is examined. Simultaneity is found to arise in the implicit markets for individual characteristics because of the presence of nonlinearity in the market (hedonic) price function for housing. However, this simultaneity is not the kind discussed by S. Rosen [J. Political Econ. 82, 34–55 (1974)] between firm supplies and household demands. As a result, the Rosen suggestion of identifying demand with firm supply shifters is inappropriate. Among the alternative approaches to identification, the most desirable involve use of data over two or more markets in which residence for a given household is exogenous to the choice of housing.     

Dynamics,stability, and foresight in the Shapley–Scarf housing market

While most of the literature starting with Shapley and Scarf (1974) have considered a static exchange economy with indivisibilities, this paper studies the dynamics of such an economy. We find that both the dynamics generated by competitive equilibrium and the one generated by the weak dominance relation, converge to a set of allocations we define as strictly stable, which we can show to exist. Moreover, we show that even when only pairwise exchanges between two traders are allowed, the strictly stable allocations are attained eventually if traders are sufficiently farsighted.     

Null players,solidarity, and the egalitarian Shapley values

The Shapley value probably is the most eminent single-point solution concept for TU-games. In its standard characterization, the null player property indicates the absence of solidarity among the players. First, we replace the null player property by a new axiom that guarantees null players non-negative payoffs whenever the grand coalition’s worth is non-negative. Second, the equal treatment property is strengthened into desirability. This way, we obtain a new characterization of the class of egalitarian Shapley values, i.e., of convex combinations of the Shapley value and the equal division solution. Within this characterization, additivity and desirability can be replaced by strong differential monotonicity, which translates higher productivity differentials into higher payoff differentials.     

House prices, wealth effects, and the Singapore macroeconomy

This paper examines the effect housing wealth has upon aggregate consumption in Singapore. While past research has focused only on changes in private housing wealth, the residential market in Singapore is dominated by the public housing sector. The massive public housing segment can generate potentially different wealth effects from standard private housing markets given the former’s unique institutional features. In particular, public housing owners who sell their units at market rates can repurchase a public flat at subsidized prices whereas private homeowners typically cannot. We estimate the link between consumption expenditure and both private and public housing wealth using a VARX approach for the Q1:1990–Q4:2002 period. We find that changes in private house prices have no significant effect on aggregate consumption. In contrast, public housing wealth effects are larger and more persistent.     

The link between the Shapley value and the beta factor

In this article, we provide a link between the Shapley value in cooperative game theory and the capital asset pricing model (CAPM) in finance. In particular, the Shapley value of a suitably defined cooperative game is closely related to the beta factor in the CAPM. The beta factor for any given security may be interpreted as the asset’s fairly allocated share of the market risk or as the asset’s average marginal contribution to the market risk, respectively. Other fairness properties and axioms of the Shapley value may be reinterpreted in this context to attain a deeper understanding of the beta factor and the connotation of systematic risk. Our game theoretic approach further allows for a generalisation of the CAPM with respect to arbitrary risk measures other than variance. Last but not least, we discuss the volatility of an asset’s theoretical fair assessment of risk and of its systematic risk, respectively. This result lends itself to face the challenge of an empirical investigation on real stock markets.     

Inconsequential arbitrage

We introduce the concept of inconsequential arbitrage and, in the context of a model allowing short-sales and half-lines in indifference surfaces, prove that inconsequential arbitrage is sufficient for existence of equilibrium. Moreover, with a slightly stronger condition of nonsatiation than that required for existence of equilibrium and with a mild uniformity condition on arbitrage opportunities, we show that inconsequential arbitrage, the existence of a Pareto optimal allocation, and compactness of the set of utility possibilities are equivalent. Thus, when all equilibria are Pareto optimal — for example, when local nonsatiation holds — inconsequential arbitrage is necessary and sufficient for existence of an equilibrium. By further strengthening our nonsatiation condition, we obtain a second welfare theorem for exchange economies allowing short sales.Finally, we compare inconsequential arbitrage to the conditions limiting arbitrage of Hart [Hart, O.D., 1974. J. Econ. Theory 9, 293–311], Werner [Werner, J., 1987. Econometrica 55, abs1403–1418], Dana et al. [Dana, R.A., Le Van, C., Magnien, F., 1999. J. Econ. Theory 87, 169–193] and Allouch [Allouch, N., 1999. Equilibrium and no market arbitrage. CERMSEM, Universite de Paris I]. For example, we show that the condition of Hart (translated to a general equilibrium setting) and the condition of werner are equivalent. We then show that the Hart/Werner conditions imply inconsequential arbitrage. To highlight the extent to which we extend Hart and Werner, we construct an example of an exchange economy in which inconsequential arbitrage holds (and is necessary and sufficient for existence), while the Hart/Werner conditions do not hold.     

Weakly balanced contributions and the weighted Shapley values

We provide a concise characterization of the class of positively weighted Shapley values by three properties, two standard properties, efficiency and marginality, and a relaxation of the balanced contributions property called the weak balanced contributions property. Balanced contributions: the amount one player gains or loses when another player leaves the game equals the amount the latter player gains or loses when the former player leaves the game. Weakly balanced contributions: the direction (sign) of the change of one player’s payoff when another player leaves the game equals the direction (sign) of the change of the latter player’s payoff when the former player leaves the game. Given this characterization, the symmetric Shapley value can be “extracted”from the class of positively weighted Shapley values by either replacing the weak balanced contributions property with the standard symmetry property or by strengthening the former into the balanced contributions property.     

(Non-)Existence of Equilibria in Multicommunity Models

This paper reconsiders equilibrium existence in models with migration and voting over local public goods. We show that under some straightforward assumptions on preferences and income distributions, the basic structure of multicommunity models (i.e., perfect mobility, majority rule, single crossing property) implies that no equilibrium with jurisdictions conducting different policies can exist. Stratification equilibria—with sorting of the population according to income classes—are therefore not as natural as is sometimes suggested. Mechanisms that can serve to support stratification (i.e., tight housing markets, returns to scale in the provision of publicly consumed goods) are discussed.     

Competitive equilibria in Shapley–Scarf markets with couples

We investigate the existence and properties of competitive equilibrium in Shapley–Scarf markets involving an exogenous partition of individuals into couples. The presence of couples generates preference interdependencies which cause existence problems. For both cases of transferable and non-transferable income among partners, we establish properties for preferences that are sufficient for the existence of an equilibrium. Moreover, we show that these properties define a maximal preference domain.