Expected Log-Utility Maximization Under Incomplete Information and with Cox-Process Observations

We consider the portfolio optimization problem for the criterion of maximization of expected terminal log-utility. The underlying market model is a regime-switching diffusion model where the regime is determined by an unobservable factor process forming a finite state Markov process. The main novelty is due to the fact that prices are observed and the portfolio is rebalanced only at random times corresponding to a Cox process where the intensity is driven by the unobserved Markovian factor process as well. This leads to a more realistic modeling for many practical situations, like in markets with liquidity restrictions; on the other hand it considerably complicates the problem to the point that traditional methodologies cannot be directly applied. The approach presented here is specific to the log-utility. For power utilities a different approach is presented in the companion paper (Fujimoto et al. in Appl Math Optim 67(1):33–72, 2013).     

Equivalence of strong and coalition-proof Nash equilibria in games without spillovers

Summary This paper examines the conditions which guarantee that the set of coalition-proof Nash equilibria coincides with the set of strong Nash equilibria in the normal form games withoutspillovers. We find thatpopulation monotonicity properties of the payoff functions, when the payoff of a player changes monotonically when the size of the group of players choosing the same strategy increases, are crucial to obtain the equivalence of these two solution concepts. We identify the classes of games, satisfying population monotonicity properties, which yield the equivalence of the set of coalition-proof Nash equilibria and the set of strong Nash equilibria. We also provide sufficient conditions for the equivalence result even when the population monotonicity assumptions are relaxed.We wish to thank Mamoru Kaneko, Akihiko Matsui, Tomoichi Shinotsuka, Benyamin Shitoviz, Tayfun Sonmez, William Thomson, the participants of the Southeastern Economic Theory Meeting in Charlottesville and the seminars at CORE and University of Tsukuba for useful discussions and comments. Our special thanks due anonymous referee for the suggestion to add a section addressing the issue of existence of a strong Nash equilibrium.     

Does yardstick regulation really work? Empirical evidence from Japan’s rail industry

This paper investigates the effectiveness of yardstick regulation by using a data set of rail companies in Japan and estimating the variable frontier cost function. In the variable cost function, both the coefficient of the yardstick regulation dummy and the coefficient of the competitive pressure outside the industry show the negative sign with statistical significance, indicating that the introduction of yardstick regulation and competition tend to decrease a rail company’s variable cost. Between 1995 and 2000, railways to which yardstick regulation was applied improved cost efficiency by about 11.5%.     

Considering the Role of Affect and Anticipated Emotions in the Formation of Consumer Loyalty Intentions

Ajzen and Sheikh ( 2013 ) recently challenge calls for adding explicit measures of emotions or affect as independent constructs into the Theory of Reasoned Action (TRA). This assertion has potentially significant theoretical and operational implications for marketers in terms of parsimony and insight. The specific questions of whether or not the addition of anticipated forms of emotions and/or hedonic attitudes to traditional attitude‐based models meaningfully contributes to understanding loyalty intention formation in a retail marketing setting are empirically assessed in this research. Results suggest that, consistent with the arguments of Perugini and Bagozzi ( 2001 ), the independent addition of anticipated emotions (AEs) to attitude models such as the TRA, Theory of Planned Behavior, and Model of Goal‐Directed Behavior (MGB) can be justified in terms of model fit with data, predictive validity (?R²), and efficacy in explanation. Interestingly, however, and consistent with the theoretical arguments underlying the TRA, the models receiving the most overall support appear to be models wherein Attitude_Overall mediates the contributions of positive and negative AEs on endogenous variables such as Desires and Intentions_Loyalty. While it remains up to the individual marketer which perspective to embrace given the observed gains reported herein, the present research also supports the notion that the addition of hedonic attitude forms and/or AEs can offer an overall net gain for many marketers. The managerial and research implications of the results are discussed.     

Pure Strategy Nash Equilibrium in a Group Formation Game with Positive Externalities

This paper identifies a domain of payoff functions inno spillovernoncooperative games withPositive externalitywhich admit a pure strategy Nash equilibrium. Since in general a Nash equilibrium may fail to exist, in order to guarantee the existence of an equilibrium, we impose two additional assumptions,AnonymityandOrder preservation. The proof of our main result is carried out by constructing, for a given gameG, a potential function Ψ over the set of strategy profiles in such a way that the maximum of Ψ yields a Nash equilibrium in pure strategies ofG.Journal of Economics LiteratureClassification Numbers: C72, D62, H73.     

Moral intensity,moral awareness and ethical predispositions: The case of insurance fraud

The issue of insurance fraud by consumers continues to perplex insurance firms, costing billions of dollars per year in the United States alone. Some analysts report that 10 per cent or more of property/casualty insurance claims are fraudulent, while less than 20 per cent of fraudulent claims being detected. Consumer attitudes are becoming more tolerant of insurance fraud in recent years. Recognizing that not all insurance fraud situations are created equal, we investigate variability in perceptions of moral intensity in dissimilar insurance padding situations in a 2 (to help others versus to profit self) × 2 (a small credit union versus a large online insurer) model and compared the results between two independent samples (college students/Millennials and an older adult population). We also investigated the impact of ethical predispositions (formalism and utilitarianism) on moral awareness and moral judgment using these four scenarios. The results suggest that the Millennials may exhibit more situationalism and more lenient judgments of collaborative versus unilateral ethical violations. In particular, ‘for self’ versus ‘for others’ comparisons show striking differences between the two age groups. The results add to the growing literature in explaining intra-personal variability in moral decision making.     

Tiebout's tale in spatial economies: Entrepreneurship, self-selection, and efficiency

This paper establishes the existence and efficiency of equilibrium in a local public goods economy with spatial structures by formalizing Hamilton's [Hamilton, B.W., 1975. Zoning and property taxation in a system of local governments Urban Studies 12, 205–211] elaboration of Tiebout's [Tiebout, C., 1956. A pure theory of local public expenditures. Journal of Political Economy 64, 416–424] tale. We use a well-known equilibrium concept from Rothschild and Stiglitz [Rothschild, M., Stiglitz, J.E., 1976. Equilibrium in competitive insurance markets: an essay on the economics of imperfect information. Quarterly Journal of Economics 40, 629–649] in a market with asymmetric information, and show that Hamilton's zoning policy plays an essential role in proving the existence and efficiency of equilibrium. We use an idealized large economy following Ellickson, Grodal, Scotchmer and Zame [Ellickson, B., Grodal, B., Scotchmer, S., Zame, W.R., 1999. Clubs and the market, Econometrica 67, 1185–1217] and Allouch, Conley and Wooders [Allouch, N., Conley, J.P., Wooders, M.H., The Tiebout Hypothesis: On the Existence of Pareto Efficient Competitive Equilibria, (2004), mimeograph]. Our theorem is directly applicable to the existence and efficiency of a discrete spatial approximation of mono- or multi-centric city equilibria in an urban economy with commuting time costs, even if we allow the existence of multiple qualities of (collective) residences, when externalities due to traffic congestion are not present.     

Can Small Class Policy Close the Gap? An Empirical Analysis of Class Size Effects in Japan

Can smaller classes lead to better educational outcomes and greater equality in achievement? We estimate the causal effects of class size on achievement tests by using discontinuous changes in class size under the Japanese public compulsory education system. We employ a value‐added model that uses achievement tests conducted at two different times during the same school year. Our results show that a reduction in class size has significantly positive effects on Japanese language test scores in the sixth grade, especially at schools in wealthy areas. However, we find no evidence that a universal small class policy closes the achievement gap among schools.     

Sequential formation of alliances in survival contests

We consider a sequential formation of alliances à la Bloch (1996) and Okada (1996), followed by a two‐stage contest in which alliances first compete with each other, and then the members in the winning alliance compete again for an indivisible prize. In contrast to Konishi and Pan (2019a), which adopted an open‐membership game as the alliance formation process, alliances are allowed to limit their memberships (excludable alliances). We show that if members’ efforts are strongly complementary to each other, there will be exactly two asymmetric alliances: the larger alliance is formed first and then the remaining players form the smaller one. This result contrasts with the one under open membership, where moderate complementarity is necessary to support a two‐alliance structure. It is also in stark contrast with Bloch, Sánchez‐Pagés, and Soubeyran (2006), which shows that a grand coalition is formed in the same game if the prize is divisible and a binding contract can be used to avoid further conflicts after an alliance wins the prize.