inaba.masaru at canon-igs.org
●日 時：2014/8/21, Thu, 16:30-18:00
●報告者: 山本竜市 (YAMAMOTO, Ryuichi), 早稲田大学
● Title: Dynamic predictor selection, learning horizons, and price impact in the Japanese stock market
●日 時：2014/5/8, Thu, 14:00-15:00
●報告者: 井上純一 (INOUE, Jun-ichi), 北海道大学
● Title: "Spatio-temporal pattern formation in rent distribution: A case study for city of Sapporo"
● Abstract: We propose a very simple probabilistic model to explain the spatio-temporal structures of rent distribution in city of Sapporo. Here we modify the mathematical model proposed by Gauvin et. al. . In their mathematical modeling, they utilized several assumptions to describe the decision making of each inhabitant in Paris. Namely, they assumed that the intrinsic attractiveness of a city depends on the location and there exists a single peak at the center. They also used the assumption that each inhabitant tends to choose the place where the other inhabitants having similar or superior income to himself/herself are living. In order to find the best possible (desirable) place to live, each buyer in the system moves from one place to the other according to the transition (aggregation) probability described by the above two assumptions, and he/she makes a deal with the seller who presents the best possible condition for the buyer. They concluded that the resultant self-organized rent distribution is consistent with the corresponding empirical evidence in Paris. However, it is hard for us to apply their model directly to the other cities having plural centers (not only a single center as in Paris). Hence, here we shall modify the Gauvin's model to include the much more detail structures of the attractiveness by taking into account the empirical (aggregated) data concerning the housing situation in city of Sapporo. We also consider the competition between two distances, namely, the distance between house and center, and the distance between house and office. Computer simulations are carried out to reveal the self-organized spatial structure appearing in the rent distribution. We also compare the resulting distribution with empirical rent distribution in Sapporo as an example of cities designated by ordinance.
In this talk, we present several findings such as
1) The lowest ranking agents (buyers) visit almost all of regions in city to look for their housing even though such places are highly `attractive places, whereas the highest ranking agents visit relatively high attractive places.
2) The lowest ranking agents are swept away from attractive regions and make several their own `communities' in low offering price locations (the north-east area in Sapporo).
We also discuss the possibility of the model to explain the distribution of land price in commercial area.
 L. Gauvin. A. Vignes and J.-P. Nadal , Journal of Economic Dynamics and Control, Vol. 37, Issue 7, pp. 1300-1321 (2013).
●日 時：2014/3/10, Mon, 17:00-19:30
●報告者: 山田克宣 (YAMADA, Katsunori ), ISER, Osaka University
● Title: "Parietal-striatal network plays a role in translating cardinal reward information into ordinal utility"
● Abstract: Since the Stiglitz Report was published in 2009, there has been much debate between economists and psychologists on the validity of happiness data as a policy target for economic issues. Here we provide novel biological evidence obtained from human fMRI experiments to help offer some answers to this cross-discipline debate. We found that when subjects expressed happiness with a monetary reward on an ordinal scale—a common method for collecting happiness data—the parietal–striatal network was involved in their evaluation of their happiness levels in accordance with the given scale. Because of the existence of this additional cognitive process, we suggest that conventional happiness data would be a noisy proxy of intrinsic cardinal utility.
●日 時：2014/1/23, Thu, 17:00-19:30
●報告者: 渡辺誠 (WATANABE, Makoto ), VU University Amsterdam, Tinbergen Institute
● Title: "Competition in the Presence of Individual Demand Uncertainty" (with Marc Möller)
● Abstract: This paper sheds light on an empirical controversy about the effect of competition on price discrimination. We propose a model in which consumers learn their preferences over time and show that firms offer advance purchase discounts. Consumers choose between an early (uninformed) purchase at a low price and a late (informed) purchase at a high price. Competing firms offer higher discounts to secure a large market share in advance. Competition decreases welfare and may affect consumers negatively. The empirical finding, that competition may influence price dispersion positively or negatively, can be explained by differences in the level of demand uncertainty.