Price distortion induced by a flawed stock market index

Despite the introduction of sophisticated stock market indices, investors often trade portfolios of the flawed indices to change their exposure to the market. In this study, we show that these transactions cause significant mispricing in individual stocks, especially during periods of significant market movement. As an influential, albeit flawed, stock index, we focus on the Nikkei 225. We find index constituents that are excessively weighted on the index, experience buying (selling) pressure when the stock market surges (falls), and experience price corrections after such periods of change. In contrast, non-constituent stocks do not experience such trading pressure.     

The Substitution Effect of Mobile Games on Console Games: An Empirical Analysis of the Japanese Video Game Industry

In this paper, we discuss the substitution effects between mobile games and console games. We estimate such effects by a fixed-effect regression with instrumental variables using panel data of about 100,000 observations. The results showed that the substitution effects of playing smart devices on 3DS, Wii, and PSP were recognizable, but did not have significant effects on PS3, and the substitution effects on PSP were very small. Therefore, mobile games had a substitution effect on casual console games, or on console games in which the play situation resembled mobile games. In addition, the substitution effects were at most about 0.1. The substitution effects were small. Our results indicate that mobile games represent the pioneers in the new market of gaming at least during our observation period. But new games and traditional games will coexist for a while.     

Paretian Welfare Judgements and Bergsonian Social Choice

Two distinct approaches can be identified in the new welfare economics. The school of thought based on the compensation principles attempted to see what can be said about social welfare without making interpersonal comparisons of well-being by extending the applicability of the Pareto principle through hypothetical compensatory payments between gainers and losers. The Bergson-Samuelson school of thought introduced the social welfare function as a formal method of introducing a Pareto-inclusive ethical belief on social welfare, whose policy implications we should theoretically explore. Synthesising these two approaches, this paper identifies a condition under which the new welfare economics is logically impeccable.     

Market design for standardization problems with agent-based social simulation

This paper provides a computational market model with technological competitions among standards and presents simulations of various scenarios concerning standardization problems. The market model has three features: (1) economic entities such as consumers and firms are regarded as autonomous agents; (2) micro interactions among consumer agents or firm agents have essential mechanisms interpretable in real markets; and (3) consumers’ preferences and firms’ technologies co-affect their evolutionary behavior. In recent years, consumers have experienced various inconveniences from de facto competition based on a market mechanism. Standardization communities or committees such as the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) need to design a compatible standard or a de jure standard in a market. However, it is difficult for market designers to decide a method or timing for the standardization. Here, by introducing a novel technique used in agent-based social simulation (ABSS), which we call “scenario analysis,” we aim to support such decision making. Scenario analysis provides the possible market changes that can occur following implementation of a design policy under a specific market situation and the market mechanisms that generate these market changes.     

The Boosting Effect of E-WOM on Macro-level Consumption: A Cross-Industry Empirical Analysis in Japan

In this study, we carry out an empirical analysis on how electronic word-of-mouth (hereinafter “e-WOM”) marketing on e-WOM websites and electronic-commerce websites on the Internet boosts consumption on a macro-level. In our analysis, we conduct a model analysis of consumer behavior using data composed of more than 30,000 questionnaire surveys and quantitatively find the elasticity coefficient of the boost to consumption by performing a two-step GMM (generalized method of moments), which uses instrumental variables. The results of the analysis show e-WOM significantly increased expenditures in six fields: computers, electrical appliances, etc.; music; hobbies; clothing, accessories, etc.; beauty products, etc.; and goods for everyday life, etc. Furthermore, there was no field that had a significantly negative value. These results showed that, in the majority of the target fields, e-WOM had not only the effect of winning customers from the competition, but also the effect of boosting consumption on a macro-level. In addition, even from people’s subjective evaluations, there were many in all the generational groups who said that e-WOM boosted expenditures.     

A characterization of consistent collective choice rules

We characterize a class of collective choice rules such that collective preference relations are consistent. Consistency is a weakening of transitivity and a strengthening of acyclicity requiring that there be no cycles with at least one strict preference, which excludes the possibility of a “money pump.” The properties of collective choice rules used in our characterization are unrestricted domain, strong Pareto, anonymity and neutrality. If there are at most as many individuals as there are alternatives, the axioms provide an alternative characterization of the Pareto rule. If there are more individuals than alternatives, however, further rules become available.