全文: "Mixi"
797件中 1-20の結果を表示しています
  • 野崎 浩成, 多鹿 秀継
    2011年 75 巻 1EV090
    発行日: 2011/09/15
    公開日: 2019/02/02
    会議録・要旨集 フリー
  • 松尾 豊, 安田 雪
    2007年 22 巻 5 号 531-541
    発行日: 2007年
    公開日: 2007/07/17
    ジャーナル フリー
    Our purpose here is to (1) investigate the structure of the personal networks developed on mixi, a Japanese social networking service (SNS), and (2) to consider the governing mechanism which guides participants of a SNS to form an aggregate network. Our findings are as follows:the clustering coefficient of the network is as high as 0.33 while the characteristic path lenght is as low as 5.5. A network among central users (over 300 edges) consist of two cliques, which seems to be very fragile. Community-affiliation network suggests there are several easy-entry communities which later lead users to more high-entry, unique-theme communities. The analysis on connectedness within a community reveals the importance of real-world interaction. Lastly, we depict a probable image of the entire ecology on {\\em mixi} among users and communities, which contributes broadly to social systems on the Web.
  • Tomohiro NAKAO, Jun-nosuke TERAMAE, Naoki WAKAMIYA
    IEICE Transactions on Communications
    2016年 E99.B 巻 11 号 2280-2288
    発行日: 2016/11/01
    公開日: 2016/11/01
    ジャーナル 認証あり

    Due to rapid increases in the number of users and diversity of devices, temporal fluctuation of traffic on information communication network is becoming large and rapid recently. Especially, sudden traffic changes such as flash crowds often cause serious congestion on the network and result in nearly fatal slow down of date-communication speed. In order to keep communication quality high on the network, routing protocols that are scalable and able to quickly respond to rapid, and often unexpected, traffic fluctuation are highly desired. One of the promising approaches is the distributed routing protocol, which works without referring global information of the whole network but requires only limited informatin of it to realize route selection. These approaches include biologically inspired routing protocols based on the Adaptive Response by Attractor Selection model (ARAS), in which routing tables are updated along with only a scalar value reflecting communication quality measured on each router without evaluating communication quality over the whole network. However, the lack of global knowledge of the current status of the network often makes it difficult to respond promptly to traffic changes on the network that occurs at outside of the local scope of the protocol and causes inefficient use of network resources. In order to solve the essential problem of the local scope, we extend ARAS and propose a routing protocol with active and stochastic route exploration. The proposed protocol can obtain current communication quality of the network beyond its local scope and promptly responds to traffic changes occur on the network by utilizing the route exploration. In order to compensate destabilization of routing itself due to the active and stochastic exploration, we also introduce a short-term memory to the dynamics of the proposed attractor selection model. We conform by numerical simulations that the proposed protocol successfully balances rapid exploration with reliable routing owning to the memory term.

  • 丸井 淳己, 加藤 幹生, 松尾 豊, 安田 雪
    2010年 JSAI2010 巻 3A2-3
    発行日: 2010年
    公開日: 2018/07/30
    会議録・要旨集 フリー

    今や主要なウェブサービスの一つとなったSNSには非常に大規模な人間関係が構成され,社会的な重要性が増し続けている.我々はmixiのリンク構造とアクセスログを調査し,基礎的な性質を示すと共に年代による人間関係の違いを明らかにした.次にリンクのクラスタリングを行い5種類の人間関係に分類した.さらに5種類の共起具合をNetwork motifを用いて計算し,情報の流れるパスの局所的な性質を明らかにした.

  • 五味 壮平
    2012年 JSAI2012 巻 2P1-OS-9b-1
    発行日: 2012年
    公開日: 2018/07/30
    会議録・要旨集 フリー

    twitter、Facebook、mixi、そして地域SNSなどのソーシャルメディアが 普及してから数年がたち、それぞれ社会の中で浸透・定着しつつある。 その中で各サービス上で生じるコミュニケーションのあり方にもかなり 明確な差異が見られる。 本講演では、これらのサービスが採用しているアーキテクチャ とそこで生じるコミュニケーションのあり方の関係について考察する。

  • 笠原 健治
    2006年 5 巻 4 号 273-280
    発行日: 2006/04/25
    公開日: 2018/03/11
    ジャーナル フリー


  • 鳥海 不二夫, 山本 仁志, 諏訪 博彦, 岡田 勇, 和泉 潔, 橋本 康弘
    2010年 25 巻 1 号 78-89
    発行日: 2010年
    公開日: 2010/01/06
    ジャーナル フリー
    In recent years, application of Social Networking Services (SNS) and Blogs are growing as new communication tools on the Internet. Several large-scale SNS sites are prospering; meanwhile, many sites with relatively small scale are offering services. Such small-scale SNSs realize small-group isolated type of communication while neither mixi nor MySpace can do that. However, the studies on SNS are almost about particular large-scale SNSs and cannot analyze whether their results apply for general features or for special characteristics on the SNSs. From the point of view of comparison analysis on SNS, comparison with just several types of those cannot reach a statistically significant level. We analyze many SNS sites with the aim of classifying them by using some approaches. Our paper classifies 50,000 sites for small-scale SNSs and gives their features from the points of network structure, patterns of communication, and growth rate of SNS. The result of analysis for network structure shows that many SNS sites have small-world attribute with short path lengths and high coefficients of their cluster. Distribution of degrees of the SNS sites is close to power law. This result indicates the small-scale SNS sites raise the percentage of users with many friends than mixi. According to the analysis of their coefficients of assortativity, those SNS sites have negative values of assortativity, and that means users with high degree tend to connect users with small degree. Next, we analyze the patterns of user communication. A friend network of SNS is explicit while users' communication behaviors are defined as an implicit network. What kind of relationships do these networks have? To address this question, we obtain some characteristics of users' communication structure and activation patterns of users on the SNS sites. By using new indexes, friend aggregation rate and friend coverage rate, we show that SNS sites with high value of friend coverage rate activate diary postings and their comments. Besides, they become activated when hub users with high degree do not behave actively on the sites with high value of friend aggregation rate and high value of friend coverage rate. On the other hand, activation emerges when hub users behave actively on the sites with low value of friend aggregation rate and high value of friend coverage rate. Finally, we observe SNS sites which are increasing the number of users considerably, from the viewpoint of network structure, and extract characteristics of high growth SNS sites. As a result of discrimination on the basis of the decision tree analysis, we can recognize the high growth SNS sites with a high degree of accuracy. Besides, this approach suggests mixi and the other small-scale SNS sites have different character trait.
  • 安田 雪, 松尾 豊
    2007年 6 巻 4 号 155-170
    発行日: 2007/04/25
    公開日: 2018/03/05
    ジャーナル フリー
  • 根来 龍之, 大嵜 昌子, 木村 俊也
    経営情報学会 全国研究発表大会要旨集
    2012年 2012s 巻 A1-3
    発行日: 2012年
    公開日: 2012/07/25
    会議録・要旨集 フリー
  • 澁谷 覚
    2014年 11 巻 163-166
    発行日: 2014年
    公開日: 2018/10/23
    ジャーナル フリー
  • 中川 昌美
    1968年 38 巻 2 号 B73-
    発行日: 1968/10/20
    公開日: 2017/10/02
    ジャーナル フリー
  • 麻生 要一
    2006年 5 巻 3 号 209-224
    発行日: 2006/03/25
    公開日: 2018/03/11
    ジャーナル フリー


  • 足代 訓史
    2012年 1 巻 1 号 32-37
    発行日: 2012年
    公開日: 2013/06/12
    ジャーナル フリー
  • 太幡 直也, 佐藤 広英
    2016年 25 巻 1 号 26-34
    発行日: 2016/07/01
    公開日: 2016/06/04
    ジャーナル フリー
    本研究の目的は,ソーシャル・ネットワーキング・サービス上での自己情報公開を規定する心理的要因を検討することであった。mixi利用者1,051名を対象にウェブ調査を実施し,プロフィール上での自己情報公開や,情報プライバシーなどの心理的要因に関する項目に回答するように求めた。その結果,自己の属性情報(e.g., 性別),識別情報(e.g., 本名)への情報プライバシーが低いほど,不特定他者への自己情報公開数が多く,また,プロフィール上の自己表出性が高かった。一方,人気希求,犯罪被害へのリスク認知が高いほど,プロフィール上の自己表出性が高かった。
  • 加藤 千枝
    2013年 2 巻 1 号 31-43
    発行日: 2013/06/30
    公開日: 2017/02/04
    ジャーナル フリー
  • Ayana TANIGAWA
    Japan Social Innovation Journal
    2012年 2 巻 1 号 82-83
    発行日: 2012/03/05
    公開日: 2013/04/09
    ジャーナル フリー
  • Hirahara Yuki, Toriumi Fujio, Sugawara Toshiharu
    論文ID: JWEIN-K
    発行日: 2015/11/01
    [早期公開] 公開日: 2016/01/28
    ジャーナル フリー 早期公開
    We propose an SNS-norms game to model behavioral strategies in social networking services (SNSs) and investigate the conditions required for the evolution of cooperation-dominant situations. SNSs such as Facebook and Google+ are indispensable social media for a variety of social communications ranging from personal chats to business and political campaigns, but we do not yet fully understand why they thrive and whether these currently popular SNSs will remain in the future. A number of studies have attempted to understand the conditions or mechanisms that keep social media thriving by using a meta-rewards game that is the dual form of a public goods game or by analyzing user roles. However, the meta-rewards game does not take into account the unique characteristics of current SNSs. Hence, in this work we propose an SNS-norms game that is an extension of Axelrod's metanorms game, similar to meta-rewards games, but that considers the cost of commenting on an article and who is most likely to respond to it. We then experimentally investigated the conditions for a cooperation-dominant situation, by which we mean many users continuing to post articles on an SNS. Our results indicate that relatively large rewards compared to the cost of posting articles and comments are required to evolve cooperation-dominant situations, but optional responses with lower cost, such as ``Like!'' buttons, facilitate the evolution. This phenomenon is of interest because it is quite different from those shown in previous studies using meta-rewards games. We also confirmed the same phenomenon in an additional experiment using a network structure extracted from real-world SNS data.
    Journal of Socio-Informatics
    2012年 5 巻 1 号 73-80
    発行日: 2012/09/30
    公開日: 2017/02/04
    ジャーナル フリー
    Social Recruiting called So-Katsu in Japan attracts much attention in 2011. Many job searching university students use social media such as Facebook or Twitter to collect information and to communicate with each other or employees. Especially Facebook is expected to be a main communication platform between university students and employees. This study illustrates the outline of So-Katsu and examines "activation level" of Facebook recruiting pages. The result from a survey of Facebook recruiting pages (N=403) suggests that there is no definite correlation between the number of "activation level" and that of "like" or "people talking about". The poor correlation between "activation level" and "like" reveals that whether the Facebook recruiting page is active or not, is not influenced by whether the page is popular or not. From this viewpoint, Facebook recruiting pages may be a chance for low profile companies to increase their awareness, and recruit good students. However, at the same time, "Scale free" model in Facebook recruiting pages suggests the trend that new vertices (students) attach preferentially to sites (Facebook recruiting pages) which are already well connected ("liked" or "people taking about").
  • 小川 美香子
    経営情報学会 全国研究発表大会要旨集
    2012年 2012f 巻 E4-2
    発行日: 2012年
    公開日: 2013/01/30
    会議録・要旨集 フリー
  • 和田 崇
    2009年 61 巻 5 号 392-408
    発行日: 2009年
    公開日: 2018/01/10
    ジャーナル フリー

    This article attempts to examine the characteristics of a social networking service managed locally as a communication space by using the website “Stacomi” as an example. Its management, the characteristics of its users, the social networks of the users, and network-related events hosted in real space were analyzed.

    Stacomi was founded in Okayama Prefecture by a venture enterprise (Standard Co.) whose aim is to make local governance in Okayama more active. Most users live in Okayama City, probably because personal invitations sent by Standard Co. staff members, who are Okayama residents themselves, are a primary method of recruitment. Highly motivated users who require extensive social connections for their businesses use Stacomi primarily as a database for tracking regional news, as a medium for drawing participants to events, or as a tool for attracting new customers. Stacomi includes hubs that are divided into two types: groups of users who have ties to many popular users and are eager to recruit new participants, and groups of users who have ties to other hubs and wish to increase the number of their acquaintances.

    The communities active on Stacomi include three types: those featuring users who form groups in real space devoted to a common interest or common goals and use Stacomi as a social medium; those featuring users who met on Stacomi and thereafter plan and manage events in real space,; and those featuring users whose primary aim is to share news related to the area in which they live. The “Okayama Culture Zone,” for example, provides a link between hubs that leads to links between different clusters in the same area. This cooperation between hubs and active users results in an enrichment of the activities held in real space.

    Two types of events are hosted in real space: those that Standard Co. strategically plans and manages, and those that users facilitate to either engage in previously planned activities or plan new activities. The participants in these events are also divided into two types: users who need information for their businesses and are eager to form new social ties, and users who need information for their daily lives and wish to maintain contact with old acquaintances.