## SHINODA MasatoFaculty Division of Natural Sciences Research Group of Mathematics Professor |

Last Updated :2021/06/02

- パーコレーション、相転移、フラクタル、数理ゲーム

- Apr. 2013, Professor, Division of Natural Sciences, Nara Women's University
- Apr. 2012 Mar. - 2013, Assosiate Professor, Division of Natural Sciences, Nara Women's University
- Apr. 2007 Mar. - 2012, Assosiate Professor, Faculty of Science, Nara Women's University
- Jul. 2003 Mar. - 2007, Assosiate Professor, Faculty of Science, Nara Women's University
- Aug. 1996 Jun. - 2003, Lecturer, Faculty of Science, Nara Women's University
- Oct. 1994 Jul. - 1996, Research Assistant, Faculty of Sciences, Nara Women's University

- Apr. 1994, Sep. - 1994, The University of Tokyo, Graduate School, Division of Mathematical Sciences, 数理科学
- Apr. 1992, Mar. - 1994, The University of Tokyo, Graduate School, Division of Mathematical Sciences
- Apr. 1988, Mar. - 1992, The University of Tokyo, Faculty of Science, 数学科

Crowdsourcing Mechanism Design

Crowdsourcing is becoming increasingly popular in various tasks. Although the cost incurred by workers in crowdsourcing is lower than that by experts, the possibility of errors in the former generally exceeds that of the latter. One of the important approaches to quality control of crowdsourcing is based on mechanism design, which has been used to design a game’s rules/protocols so that agents have incentives to truthfully declare their preferences, and designers can select socially advantageous outcomes. Thus far, mechanism design has been conducted by professional economists or computer scientists. However, it is difficult to recruit professional mechanism designers, and developed mechanisms tend to be difficult for people to understand. Crowdsourcing requesters have to determine how to assign tasks to workers and how to reward them. Therefore, a requester can be considered to be an “amateur mechanism designer”. This paper introduces the “wisdom of the crowd” approach to mechanism design, i.e., using crowdsourcing to explore the large design space of incentive mechanisms. We conducted experiments to show that crowd mechanism designers can develop sufficiently diverse candidates for incentive mechanisms and they can choose appropriate mechanisms given a set of candidate mechanisms. We also studied how the designers’ theoretical, economic, and social tendencies, as well as their views on the world, justifiably affect the mechanisms they propose., Springer Verlag, 2017, Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 10621, 495 - 503, doiInternational conference proceedings

Flexible Reward Plans to Elicit Truthful Predictions in Crowdsourcing.

AAAI Press, 2015, Proceedings of the Third AAAI Conference on Human Computation and Crowdsourcing, HCOMP 2015, November 8-11, 2015, San Diego, California., 28 - 29, url;urlFlexible Reward Plans for Crowdsourced Tasks

We develop flexible reward plans to elicit truthful predictive probability distribution over a set of uncertain events from workers. In general, strictly proper scoring rules for categorical events only reward a worker for an event that actually occurred. However, different incorrect predictions vary in quality, and the principal would like to assign different rewards to them, according to her subjective similarity among events; e.g. a prediction of overcast is closer to sunny than rainy. We propose concrete methods so that the principal can assign rewards for incorrect predictions according to her similarity between events. We focus on two representative examples of strictly proper scoring rules: spherical and quadratic, where a worker's expected utility is represented as the inner product of her truthful predictive probability and her declared probability. In this paper, we generalize the inner product by introducing a reward matrix that defines a reward for each prediction-outcome pair. We first show that if the reward matrix is symmetric and positive definite, both the spherical and quadratic proper scoring rules guarantee the maximization of a worker's expected utility when she truthfully declares her prediction. We next compare our rules with the original spherical/quadratic proper scoring rules in terms of the variance of rewards obtained by workers. Finally, we show our experimental results using Amazon Mechanical Turk., SPRINGER-VERLAG BERLIN, 2015, PRIMA 2015: PRINCIPLES AND PRACTICE OF MULTI-AGENT SYSTEMS, 9387, 400 - 415, doi;web_of_scienceInternational conference proceedings

人間側から見るコンピュータ将棋の強さ

Nov. 2014, 知能と情報（日本知能情報ファジィ学会誌）, 26 (5), 204-211Uniform spanning trees on Sierpinski graphs

We study spanning trees on Sierpinski graphs (i.e., finite approximations to the Sierpinski gasket) that are chosen uniformly at random. We construct a joint probability space for uniform spanning trees on every finite Sierpinski graph and show that this construction gives rise to a multi-type Galton-Watson tree. We derive a number of structural results, for instance on the degree distribution. The connection between uniform spanning trees and loop-erased random walk is then exploited to prove convergence of the latter to a continuous stochastic process. Some geometric properties of this limit process, such as the Hausdorff dimension, are investigated as well. The method is also applicable to other self-similar graphs with a sufficient degree of symmetry., IMPA, 2014, ALEA-LATIN AMERICAN JOURNAL OF PROBABILITY AND MATHEMATICAL STATISTICS, 11 (2), 737 - 780, web_of_scienceScientific journal

Quality-Control Mechanism utilizing Worker's Confidence for Crowdsourced Tasks

2013, Proceedings of the Twelfth International Conference on Autonomous Agents and Multiagent Systems (AAMAS2013), 1347-1348Ability Grouping of Crowd Workers via Reward Discrimination

2013, Proceedings of Conference on Human Computation & Croudsourcingクラウドソーシングにおける品質コントロールの一考察

Oct. 2012, 合同エージェントワークショップ&シンポジウム2012Optimal strategy for 3*N AB games

Jun. 2012, IPSJ Journal, 53 (6), 1-6Winning strategy of the memory game

Nov. 2008, IPSJ Symposium Series Vol.2008, (11), 181-188Non-existence of phase transition of oriented percolation on Sierpinski carpet lattices

A percolation problem on Sierpinski carpet lattices is considered. It is obtained that the critical probability of oriented percolation is equal to 1. In contrast it was already shown that the critical probability p(c) of percolation is strictly less than 1 in Kumagai [9]. This result shows a difference between fractal-like lattice and Z(d) lattice., SPRINGER-VERLAG, Mar. 2003, PROBABILITY THEORY AND RELATED FIELDS, 125 (3), 447 - 456, doi;web_of_scienceScientific journal

Existence of phase transition of percolation on Sierpnski carpet lattices

We study Bernoulli bond percolation on Sierpinski carpet lattices, which is a class of graphs corresponding to generalized Sierpinski carpets. In this paper we give a sufficient condition for the existence of a phase transition on the lattices. The proof is suitable for graphs which have self-similarity. We also discuss the relation between the existence of a phase transition and the isoperimetric dimension., APPLIED PROBABILITY TRUST, Mar. 2002, JOURNAL OF APPLIED PROBABILITY, 39 (1), 1 - 10, web_of_scienceScientific journal

Lower estimate for the critical line of contact processes

2001, Transactions of the Materials Research Society of Japan, 26 (1), 389 - 392Percolation on the pre-Sierpinski gasket

1996, Osaka Journal of Mathematics, 33 (2), 533 - 554Scientific journal

求積法の変遷を探る学習－高等学校数学科授業の多角的観点からの検討－

Oct. 2017, 教育システム研究（奈良女子大学教育システム研究開発センター）, 別冊, 95-100A Cat-and-Mouse game on the set of integers

Jul. 2017, IPSJ SIG Technical Reportクラウドソーシングにおける必要ワーカ数の動的決定方法の提案

2013, 第27回人工知能学会全国大会クラウドソーシングでのタスク品質改善のための価格設定の検討

2013, 第27回人工知能学会全国大会Existence of phase transition of percolation on Sierpinski carpet lattices

Mar. 2012, COE Lecture Note Series (Institute of Mathematics for Industry, Kyushu University), 39, 12-21Optimal strategy of the memory game with special cards

Jun. 2010, IPSJ SIG Technical Report

人間に勝つコンピュータ将棋の作り方

技術評論社, Sep. 2012 (ISBN: 9784774153261)確率論ハンドブック

丸善出版, Jul. 2012, 439-442 (ISBN: 9784621065174)確率論・統計学入門

共立出版, Mar. 2008Percolation on fractal lattices ; Asymptotic behavior of the correlation length

Advances in Nonlinear Partial Differential Equations and Stochastics, World Scientific, 1998, 331-351頁

数当てゲームの最適戦略

第4回日本組合せゲーム理論研究集会, Aug. 2020Existence of phase transition of percolation on fractal lattices

Hanoi University of Science, Oct. 2019Pre-Sierpinski gasket上のpercolation再訪

研究集会「確率解析の諸相」, Jan. 2018A Cat-and Mouse game on the set of integers

IPSJ-SIG, Jul. 2017, 倉敷市芸文館強いコンピュータ将棋を作るための数学

奈良女子大学人間文化研究科2015年度数学と物理学と情報科学の研究交流シンポジウム, Dec. 2015, 奈良女子大学数当てゲームの最適戦略

新潟確率論ワークショップ, Dec. 2013, 新潟大学南キャンパス「ときめいと」Random spanning trees on Sierpinski gasket graphs

12th workshop on Stochastic Analysis on Large Scale Interacting Systems, Nov. 2013, Tokyo University強いコンピュータ将棋の作り方

日本数学会2013年度秋季総合分科会応用数学分科会, Sep. 2013, 愛媛大学コンピュータ将棋の不思議

情報処理学会第74回全国大会, Mar. 2012, 名古屋工業大学Winning strategy of the memory game

新潟確率論ワークショップ, Jan. 2012, 新潟大学Existence of phase transition of percolation on fractal lattices

Multiscale Mathematics: Hierarchy of Collective Phenomena and Interrelations between Hierarchical Structures, Dec. 2011, Institute of Mathematics for Industry, Kyushu Universitypre-Sierpinski gasketでのminimal spanning treeとpercolation

フラクタルの数学的諸相, Feb. 2011Random spanning trees on the Sierpinski gasket

確率論とその周辺, Dec. 2010, 京都大学数理解析研究所Random spanning trees on the Sierpinski gasket

34th Conference on Stochastic Processes and Their Applications, Sep. 2010, Senri Life Science Center BuildingUniform spanning trees and loop-erased random walks on the pre-Sierpinski gasket

日本数学会, Sep. 2009