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Analysis, generation and prediction of social networks using event sequences

Research Project

Project/Area Number 19H04214
Research Category

Grant-in-Aid for Scientific Research (B)

Allocation TypeSingle-year Grants
Section一般
Review Section Basic Section 62020:Web informatics and service informatics-related
Research InstitutionUniversity of Tsukuba

Principal Investigator

Oka Mizuki  筑波大学, システム情報系, 准教授 (10512105)

Co-Investigator(Kenkyū-buntansha) 池上 高志  東京大学, 大学院総合文化研究科, 教授 (10211715)
橋本 康弘  会津大学, コンピュータ理工学部, 上級准教授 (10376494)
CHEN DOMINIQUE  早稲田大学, 文学学術院, 准教授 (50801784)
Project Period (FY) 2019-04-01 – 2022-03-31
Project Status Completed (Fiscal Year 2021)
Budget Amount *help
¥15,730,000 (Direct Cost: ¥12,100,000、Indirect Cost: ¥3,630,000)
Fiscal Year 2021: ¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000)
Fiscal Year 2020: ¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000)
Fiscal Year 2019: ¥6,110,000 (Direct Cost: ¥4,700,000、Indirect Cost: ¥1,410,000)
KeywordsMultivariate Hawkes過程 / ネットワーク分析 / 臨界状態 / キーストーン種 / 多変量ホークス過程 / ソーシャルネットワーク / 時系列データ / 人工生命 / 複雑系 / テンポラルネットワーク / embedding / Hawkes Process / Hawkes過程 / SNS / キーストーン / Hawkes process / ソーシャルネットワークサービス
Outline of Research at the Start

SNSといったオンラインコミュニケーションには、その背後にダイナミックなネットワーク構造があることがわかってきた。そうしたネットワークの解析には、ネットワークの生成的数理モデルが有効である。実データを数理モデルの生成するデータと照らし合わせ、パラメータを推定することで、解析は一気に進む。生成系のモデルの利点は、取得できるデータが少ない場合の解析に強く、パラメータの変更により条件を変えることで、ネットワークの生成や成長の予想をすることが可能な点にある。本研究では、生成モデルの一つであるHawkes Processを用いて、ネットワークの生成や成長の予測を行う。

Outline of Final Research Achievements

It is said that birds are able to form flocks because they act in a 'critical area', where the movements of a single bird are linked in a chain and propagated to the whole group. In this study, we analyzed whether a similar critical phenomenon exists in internet communication systems. The analysis revealed the existence of a critical phenomenon in online communication, which is observed in a critical region with two states of different nature. It was also found that when a group is in a critical state, nodes emerge that behave like 'keystone' species in biological ecosystems. These mechanisms are thought to enhance the metabolism of the group, leading to the sustainability and adaptability of online communication.

Academic Significance and Societal Importance of the Research Achievements

過剰に安定したシステムは、それゆえに新しいものが生まれず、そのままでは多様性が損なわれしまい、変化が起きたときに適応できず、システムそのものが壊れてしまう危険性がある。本研究の結果から、適応的なシステムを作り出すためには、キーストーン種のような不安定性を自ら作り出し、自分自身をアップデートするような機構を内在していることが重要であることが明らかとなった。これは、組織運営やシステム設計にも活かすことのできる一般的な知見となり得ると考えている。

Report

(4 results)
  • 2021 Annual Research Report   Final Research Report ( PDF )
  • 2020 Annual Research Report
  • 2019 Annual Research Report
  • Research Products

    (8 results)

All 2022 2021 2020 2019

All Journal Article (3 results) (of which Int'l Joint Research: 1 results,  Peer Reviewed: 3 results,  Open Access: 2 results) Presentation (4 results) (of which Int'l Joint Research: 3 results,  Invited: 1 results) Book (1 results)

  • [Journal Article] Predicting partially observed processes on temporal networks by Dynamics-Aware Node Embeddings (DyANE)2021

    • Author(s)
      Sato, K., Oka, M., Barrat, A. et al
    • Journal Title

      EPJ Data Sci.

      Volume: 10 Issue: 1 Pages: 1-20

    • DOI

      10.1140/epjds/s13688-021-00277-8

    • NAID

      120007192292

    • Related Report
      2020 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Analysis and Modeling of Social Tagging Using Yule–Simon Process2019

    • Author(s)
      Nishikawa Yoshimasa、Oka Mizuki、Hashimoto Yasuhiro、Ikegami Takashi
    • Journal Title

      Transactions of the Japanese Society for Artificial Intelligence

      Volume: 34 Issue: 4 Pages: C-IC3_1-8

    • DOI

      10.1527/tjsai.C-IC3

    • NAID

      130007674567

    • ISSN
      1346-0714, 1346-8030
    • Year and Date
      2019-07-01
    • Related Report
      2019 Annual Research Report
    • Peer Reviewed / Open Access
  • [Journal Article] Open-Ended Evolution and a Mechanism of Novelties in Web Services2019

    • Author(s)
      Ikegami Takashi、Hashimoto Yasuhiro、Oka Mizuki
    • Journal Title

      Artificial Life

      Volume: 25 Issue: 2 Pages: 168-177

    • DOI

      10.1162/artl_a_00287

    • Related Report
      2019 Annual Research Report
    • Peer Reviewed
  • [Presentation] Exploring online social ecosystems through bio-inspired perspectives2022

    • Author(s)
      Mizuki Oka
    • Organizer
      27th International Symposium on Artificial Life and Robotics
    • Related Report
      2021 Annual Research Report
    • Invited
  • [Presentation] Exploration in Evolutionary Space by Hashtag Evolution on a Social Network Service2021

    • Author(s)
      Hiroki Sato, Yasuhiro Hashimoto, Mizuki Oka, Takashi Ikegami
    • Organizer
      ALIFE 2021: The 2021 Conference on Artificial Life
    • Related Report
      2021 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Web as an Evolutionary Ecosystem: Emergence of Keystone Species2020

    • Author(s)
      Palin Choviwatana, Shota Ejima, Mizuki Oka, Takashi Ikegami
    • Organizer
      The 2020 Conference on Artificial Life
    • Related Report
      2020 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Concept of Keystone Species in Web Systems: Identifying Small Yet Influential Online Bulletin Board Threads2019

    • Author(s)
      Shota Ejima, Mizuki Oka, Takashi Ikegami
    • Organizer
      Proc. of the 11th ACM Conference on Web Science
    • Related Report
      2019 Annual Research Report
    • Int'l Joint Research
  • [Book] ALIFE|人工生命 ―より生命的なAIへ2022

    • Author(s)
      岡瑞起
    • Total Pages
      240
    • Publisher
      ビー・エヌ・エヌ
    • ISBN
      9784802511261
    • Related Report
      2021 Annual Research Report

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Published: 2019-04-18   Modified: 2023-01-30  

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