Followee recommendation based on text analysis of micro-blogging activity

Nowadays, more and more users keep up with news through information streams coming from real-time micro-blogging activity offered by services such as Twitter. In these sites, information is shared via a followers/followees social network structure in which a follower receives all the micro-blogs from his/her followees. Recent research efforts on understanding micro-blogging as a novel form of communication and news spreading medium have identified three different categories of users in these systems: information sources, information seekers and friends. As social networks grow in the number of registered users, finding relevant and reliable users to receive interesting information becomes essential. In this paper we propose a followee recommender system based on both the analysis of the content of micro-blogs to detect users' interests and in the exploration of the topology of the network to find candidate users for recommendation. Experimental evaluation was conducted in order to determine the impact of different profiling strategies based on the text analysis of micro-blogs as well as several factors that allows the identification of users acting as good information sources. We found that user-generated content available in the network is a rich source of information for profiling users and finding like-minded people.     

Perceived bridging and bonding social capital on Twitter: Differentiating between followers and followees

The present study investigates the influence of Twitter use and the number of followers and followees on perceived bridging and bonding online social capital. Data from a convenience sample of Twitter users (N = 264) indicate that bonding social capital is associated with the number of followers whereas bridging social capital is influenced by the number of followees. Thus, the directed friendship model on Twitter affects different forms of social capital differently. In addition, the study found a negative curvilinear effect of the number of followees on bridging and the number of followers on bonding online social capital. This indicates that the number of followees/followers has positive effects on online bridging/bonding social capital, but only to a certain point. The paper concludes with a discussion of the results in light of theoretical considerations and of implications for future research on the effects of Twitter on social capital.     

基于文本引导的注意力图像转发预测排序网络

转发预测在社交媒体网站(Social media sites, SMS)中是一个很有挑战性的问题. 本文研究了SMS中的图像转发预测问题, 预测用户再次转发图像推特的图像共享行为. 与现有的研究不同, 本文首先提出异构图像转发建模网络(Image retweet modeling, IRM), 所利用的是用户之前转发图像推特中的相关内容、之后在SMS中的联系和被转发者的偏好三方面的内容. 在此基础上, 提出文本引导的多模态神经网络, 构建新型多方面注意力排序网络学习框架, 从而学习预测任务中的联合图像推特表征和用户偏好表征. 在Twitter的大规模数据集上进行的大量实验表明, 我们的方法较之现有的解决方案而言取得了更好的效果.     

Detecting and tagging users’ social circles in social media

As a media and communication platform, microblog becomes more popular around the world. Most users follow a large number of celebrities and public medias on microblog; however, these celebrities do not necessarily follow all their fans. Such one-way relationship abounds in ego network and is displayed by the forms of users’ followees and followers, which make it difficult to identify users’ real friends who are contained in merged lists of followees and followers. The aim of this paper is to propose a general algorithm for detecting users’ real friends in social media and dividing them into different social circles automatically according to the closeness of their relationships. Then we analyze these social circles and detect social attributes of these social circles. To verify the effectiveness of the proposed algorithm, we build a microblog application which displays algorithm results of social circles for users and enables users to adjust proposed results according to her/his real social circles. We demonstrate that our algorithm is superior to the traditional clustering method in terms of F value and mean average precision. Furthermore, our method of tagging social attributes of social circles gets high performance by NDCG (normalized discounted cumulative gain).     

Credibility of Social Network Sites for Political Information Among Politically Interested Internet Users

Scholars have confirmed that political candidates are increasingly turning to social network sites (SNS) to persuade voters to vote for them, and that these sites have become prominent sources of political information. But a fundamental question arises about the sustainability of social networks as a campaign tool: How much do users trust the information they find there? This study employed an online survey to examine the degree to which politically interested online users view SNS as credible. SNS were ranked the least credible among the nine traditional and online sources examined. Reliance on social networks proved the strongest predictor of SNS credibility.     

Discerning individual interests and shared interests for social user profiling

Traditionally, research about social user profiling assumes that users share some similar interests with their followees. However, it lacks the studies on what topic and to what extent their interests are similar. Our study in online sharing sites reveals that besides shared interests between followers and followees, users do maintain some individual interests which differ from their followees. Thus, for better social user profiling we need to discern individual interests (capturing the uniqueness of users) and shared interests (capturing the commonality of neighboring users) of the users in the connected world. To achieve this, we extend the matrix factorization model by incorporating both individual and shared interests, and also learn the multi-faceted similarities unsupervisedly. The proposed method can be applied to many applications, such as rating prediction, item level social influence maximization and so on. Experimental results on real-world datasets show that our work can be applied to improve the performance of social rating. Also, it can reveal some interesting findings, such as who likes the “controversial” items most, and who is the most influential in attracting their followers to rate an item.     

社交网Twitter平台的人物关系网社区发现

社交网络服务（social networking service,SNS）已融入到大众生活中。人们将自己的信息上传到网络中,并通过社交网站管理自己的社交圈子,由此造成大量的个人信息在社交网络上被公开。文章基于Twitter平台,设计实现了Twitter用户关系网的社区发现。通过实时采集Twitter用户信息,重建人物关系网,改进Newman快速算法划分社区发现人物关系网。文章通过可视化的界面呈现用户的社区关系,提供用户网络行为,为决策者的舆情监控或个性推荐提供了参考凭据。     

Minimizing information disclosure to third parties in social login platforms

Over the past few years, a large and ever increasing number of Web sites have incorporated one or more social login platforms and have encouraged users to log in with their Facebook, Twitter, Google, or other social networking identities. Research results suggest that more than two million Web sites have already adopted Facebook’s social login platform, and the number is increasing sharply. Although one might theoretically refrain from such social login features and cross-site interactions, usage statistics show that more than 250 million people might not fully realize the privacy implications of opting-in. To make matters worse, certain Web sites do not offer even the minimum of their functionality unless users meet their demands for information and social interaction. At the same time, in a large number of cases, it is unclear why these sites require all that personal information for their purposes. In this paper, we mitigate this problem by designing and developing a framework for minimum information disclosure in social login interactions with third-party sites. Our example case is Facebook, which combines a very popular single sign-on platform with information-rich social networking profiles. Whenever users want to browse to a Web site that requires authentication or social interaction using a Facebook identity, our system employs, by default, a Facebook session that reveals the minimum amount of information necessary. Users have the option to explicitly elevate that Facebook session in a manner that reveals more or all of the information tied to their social identity. This enables users to disclose the minimum possible amount of personal information during their browsing experience on third-party Web sites.     

基于社交网络的一种个性化推荐算法

随着近些年社交网络的流行,如何有效地利用社交网络资源是推荐算法的热点问题,大多数推荐系统都是以评分等手段获取新的数据再通过计算给出用户推荐序列,但是如果能有效地利用社交网络资源,就可以减少评分这一步骤,对用户来说也更加便利。本文借鉴了部分社会心理学原理,提出了人与人之间由相似产生的信任度计算方法,对已有的由熟悉性产生的信任度计算方法给予改进,并与改进前作出对比,验证了其现实意义以及有效性。     

Personalized Tag Recommendation Using Social Influence

Tag recommendation encourages users to add more tags in bridging the semantic gap between human concept and the features of media object,which provides a feasible solution for content-based multimedia information retrieval.In this paper,we study personalized tag recommendation in a popular online photo sharing site - Flickr.Social relationship information of users is collected to generate an online social network.From the perspective of network topology,we propose node topological potential to characterize user’s social influence.With this metric,we distinguish different social relations between users and find out those who really have influence on the target users.Tag recommendations are based on tagging history and the latent personalized preference learned from those who have most influence in user’s social network.We evaluate our method on large scale real-world data.The experimental results demonstrate that our method can outperform the non-personalized global co-occurrence method and other two state-of-the-art personalized approaches using social networks.We also analyze the further usage of our approach for the cold-start problem of tag recommendation.     

A defence scheme against Identity Theft Attack based on multiple social networks

Recently, on-line social networking sites become more and more popular. People like to share their personal information such as their name, birthday and photos on these public sites. However, personal information could be misused by attackers. One kind of attacks called Identity Theft Attack is addressed in on-line social networking sites. After collecting the personal information of a victim, the attacker can create a fake identity to impersonate this victim and cheat the victim’s friends in order to destroy the trust relationships on the on-line social networking sites. In this paper, we propose a scheme to protect users from Identity Theft Attacks. In our work, users’ personal information can be still kept public. It means that this scheme does not violate the nature of the social networks. Compared with previous works, the proposed scheme incurs less overhead for users. Experimental results also demonstrate the practicality of the proposed scheme.     

A Web-Based Knowledge Network for Supporting Emerging Internet Applications

Although the Internet and the World Wide Web technologies have gained a tremendous amount of popularity among people and organizations, the network that these technologies created is not much more than a multimedia data network. It provides tools and services for people to browse and search for data but does not provide the facilities for automatically delivering the relevant information for supporting decision–making to the right people or applications at the right time. Nor does it provide the means for users to enter and share their knowledge that would be useful for making the right decisions. In this work, we introduce the concept of a Web–based knowledge network, which allows users and organizations to publish, not only their multimedia data, but also their knowledge in terms of events, parameterized event filters, customizable rules and triggers that are associated with their data and application systems. Operations on the data and application systems may post events over the Internet to trigger the processing of rules defined by both information providers and consumers. The knowledge network is constructed by a number of replicable software components, which can be installed at various network sites. They, together with the existing Web servers, form a network of knowledge Web servers.     

融合社会关系的社交网络情感分析综述

随着以用户为中心的Web 2.0的发展,社交网络平台以惊人的影响力渗入到生活的方方面面,对社交网络中的内容进行情感分析已经成为热点研究课题.Twitter、新浪微博等在线社交网站吸引了大量用户,通过用户间的交互,产生了许多包含用户间社会关系的信息,并且这些社会关系被广泛应用于社交网络的情感分析.融合社会关系的社交网络情...     

基于社会正则化的推荐算法研究

社会网络中包含大量的社会信息,如何从这些社会信息中发掘对用户有用的信息已成为学者和专家的研究热点。本文提出一种基于社会正则化的推荐算法:把改进的矩阵分解技术应用到社会化推荐中;利用社会网络中用户间的朋友关系来优化对用户的建模,学习更好的用户特征空间模型;利用社会网络中的标签信息建立用户和物品的关系,并利用这种关系来优化用户-物品的建模。实验结果表明,改进后的推荐算法的精确度高于传统的推荐算法,有效地解决了社会信息冗余问题。     

QoS prediction for web services based on user-trust propagation model

There is an important online role for Web service providers and users; however, the rapidly growing number of service providers and users, it can create some similar functions among web services. This is an exciting area for research, and researchers seek to to propose solutions for the best service to users. Collaborative filtering (CF) algorithms are widely used in recommendation systems, although these are less effective for cold-start users. Recently, some recommender systems have been developed based on social network models, and the results show that social network models have better performance in terms of CF, especially for cold-start users. However, most social network-based recommendations do not consider the user’s mood. This is a hidden source of information, and is very useful in improving prediction efficiency. In this paper, we introduce a new model called User-Trust Propagation (UTP). The model uses a combination of trust and the mood of users to predict the QoS value and matrix factorisation (MF), which is used to train the model. The experimental results show that the proposed model gives better accuracy than other models, especially for the cold-start problem.     

群智感知中基于社交属性及有效用户计算的任务分发机制

随着无线传感器网络的高速发展和多种移动智能设备的普及,移动群智感知(mobile crowd sensing,MCS)成为移动计算的核心。利用群智感知可完成大规模、复杂环境及社会感知任务,其中任务分发是这种应用中的一个重要环节。针对任务分发过程中存在感知环境复杂、用户数量达不到要求、收集数据质量低等问题,提出一种基于社交属性及有效用户计算的任务分发机制(effective user calculation,EUC),该机制具有根据任务来筛选用户的特点,从用户角度看,EUC考虑了用户的社会性,由用户的社交网络传递相关信息来增加平台的有效用户数;从平台的角度看,EUC可根据任务的接收和提交情况,动态调整有效用户的积分,从而保障整个系统的有效用户数。理论分析和实验结果表明,所提出的机制可提高系统的任务分发效率,并改善了收集数据的质量。     

Community detection for emerging social networks

Many famous online social networks, e.g., Facebook and Twitter, have achieved great success in the last several years. Users in these online social networks can establish various connections via both social links and shared attribute information. Discovering groups of users who are strongly connected internally is defined as the community detection problem. Community detection problem is very important for online social networks and has extensive applications in various social services. Meanwhile, besides these popular social networks, a large number of new social networks offering specific services also spring up in recent years. Community detection can be even more important for new networks as high quality community detection results enable new networks to provide better services, which can help attract more users effectively. In this paper, we will study the community detection problem for new networks, which is formally defined as the “New Network Community Detection” problem. New network community detection problem is very challenging to solve for the reason that information in new networks can be too sparse to calculate effective similarity scores among users, which is crucial in community detection. However, we notice that, nowadays, users usually join multiple social networks simultaneously and those who are involved in a new network may have been using other well-developed social networks for a long time. With full considerations of network difference issues, we propose to propagate useful information from other well-established networks to the new network with efficient information propagation models to overcome the shortage of information problem. An effective and efficient method, Cat (Cold stArT community detector), is proposed in this paper to detect communities for new networks using information from multiple heterogeneous social networks simultaneously. Extensive experiments conducted on real-world heterogeneous online social networks demonstrate that Cat can address the new network community detection problem effectively.     

Collaborative Filtering Using Dual Information Sources

Conventional collaborative-filtering methods use only one information source to provide recommendations. Using two sources - similar users and expert users - enables more effective, more adaptive recommendations. Conventional CF methods suffer from a few fundamental limitations such as the cold-start problem, data sparsity problem, and recommender reliability problem. Thus, they have trouble dealing with high-involvement, knowledge-intensive domains such as e-learning video on demand. To overcome these problems, researchers have proposed recommendation techniques such as a hybrid approach combining CF with content-based filtering. Because e-commerce Web sites for e-learning often have various product categories, extracting the many attributes of these categories for content-based filtering is extremely burdensome. So, it might be practical to overcome these limitations by improving the CF method itself.     

基于MRLT模型多关系社交网络影响力最大化研究

社交网络影响力最大化问题是基于特定的传播模型,在网络中寻找一组初始传播节点集合,通过其产生最终传播影响范围最大的一种最优化问题。已有的相关研究大多只是针对单关系社交网络,即在社交网络中只存在一种关系。但在现实中,社交网络的用户之间往往存在着多种关系,并且这多种关系共同影响着网络信息传播及其最终影响范围。在线性阈值模型的基础上,结合网络节点间存在的多种关系,提出MRLT传播模型来建模节点间的影响力传播过程,在此基础上提出基于反向可达集的MR-RRset算法,解决了传统影响力最大化问题研究过程中由于使用贪心算法所导致的计算性能较低的问题。最后通过在真实数据集上的实验对比,表明所提方法具有更好的影响力传播范围及较大的计算性能提升。     

Weaving a computing fabric

As sources of information relevant to a particular domain proliferate, we need a methodology for locating, aggregating, relating, fusing, reconciling, and presenting information to users. Interoperability thus must occur not only among the information, but also among the different software applications that process it. Given the large number of potential sources and applications, interoperability becomes an extremely large problem for which manual solutions are impractical. A combination of software agents and ontologies can supply the necessary methodology for interoperability.