一种基于用户偏好自动分类的社会媒体共享和推荐方法

社会媒体应用已成为Web应用的主流,以用户为中心并且海量媒体数据由用户自生成是社会媒体Web应用的重要特征.应对目前社会媒体环境中信息过载的问题,信息的共享和推荐机制发挥着重要的作用.文中分析了目前主流社会媒体网站基于用户自建组的信息共享机制所存在的问题以及传统推荐技术在效率上的问题,提出了一种新的基于用户偏好自动分类的社会媒体数据共享和推荐方法.直观上讲,该方法的本质是把用户对具体媒体对象的偏好转化成用户对媒体对象所蕴含兴趣元素的偏好,然后把具有相同偏好的用户,即对若干兴趣元素上的兴趣度都相同,自动聚合成为一个"共同偏好组(CPG)".文中提出了基于CPG的社会媒体信息共享和推荐的架构,设计实现了CPG的自动生成算法,通过随机生成模拟数据集实验详细分析了算法性能的影响因素,并与现有类似功能算法进行了效率对比,实验结果表明算法可适用于具有海量用户的社会媒体应用.     

基于矩阵分解模型的微博好友推荐算法

微博作为一种实时的信息传播和分享的社交网络平台,对人们日常生活的影响越来越大.在微博中,用户可以通过关注关系,添加自己感兴趣的好友,扩大自己的交际圈.但如何推荐高质量的关注好友,一直是个性化服务的难点之一.针对此种情况,提出一种微博好友推荐算法,旨在为用户推荐高质量的关注用户.该算法是对基于Seeker-Source矩阵分解模型的一种改进算法.文中分析了微博用户的多种数据源信息,并给出了相应的特征提出方法,最后将这些特征引入到Seeker-Source矩阵分解模型中,通过对模型的优化求解,得到最佳的参数因子矩阵,从而完成好友推荐.在真实的微博数据集上的实验表明,本文所提出的算法取得了良好的效果.     

话题感知下的跨社交网络影响力最大化分析

随着各种社交网站的不断涌现,在多社交网络上找到影响传播范围最大的一组用户,对产品推荐或产品推广具有重要作用。为提高产品推荐或推广的广度和精准性,提出了一种跨社交网络基于话题感知的影响力最大化处理方法M-TLTGreedy。首先,根据跨社交网络中的文本语义信息和用户间的社会关系来评价多社交网络中用户间关系,以此构建一个基于话题的跨社交网络图;然后,在线性阈值模型的基础上,设计了一个基于话题感知的跨社交网络影响力最大化模型M-TLT(multiple-topic linear threshold);接着,基于M-TLT模型,利用改进的启发式算法,进行初始用户集的选取;最后,基于大量数据集的实验,证明了该算法无论在影响范围和时间效率上均表现良好。     

基于多示例学习技术的Web目录页面链接推荐

在Web目录页面中,向用户推荐其感兴趣的链接有助于用户高效地访问网络资源.然而,用户往往不愿花费很多时间来标记训练样本,其提供的数据可能只能说明某个目录网页是否包含其感兴趣的内容,而不能明确标示出其感兴趣的具体链接.由于训练数据中缺乏对链接的标记,但预测时却需要找出用户感兴趣的链接,这就使得Web目录页面链接推荐问题相当困难.CkNN-ROI算法被提出用于解决该问题.实验表明,CkNN-ROI算法在解决这一困难的链接推荐问题上比其他一些算法更为有效.     

一种基于拉普拉斯矩阵的在线社会网络社区发现算法

Web媒体被公认为继报纸、广播、电视之后的＂第四媒体＂。而Web2.0的迅速普及,又使当今的Web媒体呈现了一种＂自媒体＂形式,即每个用户既是信息的接受者,也是信息发布者和信息转发者,因此,在当今的Web上形成了在线社会网络。研究表明在线社会网络呈现出一种很强的＂模块性＂（＂社区性＂）,因此,在在线社会网络中,社区发现一直是一个研究热点,即如何设计算法以发现大规模社会网络中的社区结构。文章提出了一种基于拉普拉斯矩阵的在线社会网络社区发现算法,该算法将在线社会网络转换成以拉普拉斯矩阵形式表现,通过计算该矩阵的谱并利用其性质发现社会网络上的社区结构。文章同时针对人造数据集与真实数据集进行了实验,实验结果表明本算法能够有效的发现社会网络中的社区结构。     

基于情感分析的个性化推荐算法研究

对基于情感分析的个性化推荐算法进行研究。为了推荐用户可能感兴趣的产品，该算法研究了以前的评级数据和用户文本评论中的情感数据，并将其与推荐算法相结合。使用情感词典和情感分类算法对文本评论进行聚类分析，并将情感得分作为评分数据的补充，然后使用基于邻域的协同过滤算法来为用户推荐物品。使用京东评论数据集进行了实验，并与其他基于协同过滤算法进行了比较。实验结果表明，该算法能够显著提高推荐准确度和用户满意度。     

基于热扩散影响力传播的社交网络个性化推荐算法

有针对性地为用户提供推荐,提高互联网信息利用率是个性化推荐系统的主要目标.文中基于热扩散传播概率模型,结合用户在社交网络中隐含的跟随关系,提出基于热扩散影响力传播的社交网络个性化推荐算法.首先,算法将现实生活中人与人的朋友关系转化为购物网络中用户与用户的跟随关系,构建异构信息网络图,计算用户之间的复合相似度.然后,利用基于热扩散概率模型模拟社会网络中影响力的传播过程,计算社交网络中用户的跟随概率分数并精确排序,筛选与目标用户相似的邻近用户.最后,根据目标邻近用户对各个产品的评分,将评分较高、具有潜在兴趣的产品推荐给目标用户,实现个性化的用户推荐.在公开数据集上与现有的个性化推荐算法进行对比,实验表明,文中算法具有较好的精确度和多样化的推荐效果.     

缺失数据下基于SVDIFC的协同过滤推荐算法

为了提高个性化推荐的准确性和质量,针对传统推荐算法的信息过载和数据稀疏性问题,构建了基于SVD与直觉模糊聚类的协同过滤推荐算法(SVDIFC-CF).算法首先引入SVD将降维后的原始矩阵进行填充;再运用用户商品喜好矩阵将用户进行直觉模糊聚类;最后计算与目标用户相似度最高的前N个用户,找到用户最感兴趣的项目作为推荐结果.采用MovieLens与Jester数据集对算法的有效性进行验证,实验结果表明相对于传统推荐算法,该算法能有效解决数据稀疏和冷启动问题,提高推荐精度与质量.     

关联规则算法在Web个性化服务中的研究与应用

重点研究了Web日志挖掘,提出了一个Web个性化信息挖掘模型,设计了某高校图书馆个性化服务系统My Library。系统采用关联规则挖掘算法,从服务器日志中得到用户感兴趣的隐式模式,并将该隐式兴趣集推荐给用户,从而在一定程度上实现了个性化服务。     

融合信任传播和奇异值分解的社会化推荐算法

针对用户信任矩阵中的数据稀疏问题,设计用户信任关系的传播规则,根据该规则计算用户之间的信任度,填充用户信任矩阵。在此基础上,结合用户信任传播算法和奇异值分解模型,提出一种社会化推荐算法,将用户评分矩阵与信任关系矩阵相结合,提高推荐系统的预测准确率。在Epinions和Filmtrust公开数据集上的实验结果表明,该算法相比传统推荐算法具有更高的推荐质量。     

A recommender system for the TV on the web: integrating unrated reviews and movie ratings

The activity of Social-TV viewers has grown considerably in the last few years—viewers are no longer passive elements. The Web has socially empowered the viewers in many new different ways, for example, viewers can now rate TV programs, comment them, and suggest TV shows to friends through Web sites. Some innovations have been exploring these new activities of viewers but we are still far from realizing the full potential of this new setting. For example, social interactions on the Web, such as comments and ratings in online forums, create valuable feedback about the targeted TV entertainment shows. In this paper, we address this last setting: a media recommendation algorithm that suggests recommendations based on users’ ratings and unrated comments. In contrast to similar approaches that are only ratings-based, we propose the inclusion of sentiment knowledge in recommendations. This approach computes new media recommendations by merging media ratings and comments written by users about specific entertainment shows. This contrasts with existing recommendation methods that explore ratings and metadata but do not analyze what users have to say about particular media programs. In this paper, we argue that text comments are excellent indicators of user satisfaction. Sentiment analysis algorithms offer an analysis of the users’ preferences in which the comments may not be associated with an explicit rating. Thus, this analysis will also have an impact on the popularity of a given media show. Thus, the recommendation algorithm—based on matrix factorization by Singular Value Decomposition—will consider both explicit ratings and the output of sentiment analysis algorithms to compute new recommendations. The implemented recommendation framework can be integrated on a Web TV system where users can view and comment entertainment media from a video-on-demand service. The recommendation framework was evaluated on two datasets from IMDb with 53,112 reviews (50 % unrated) and Amazon entertainment media with 698,210 reviews (26 % unrated). Recommendation results with ratings and the inferred preferences—based on the sentiment analysis algorithms—exhibited an improvement over the ratings only based recommendations. This result illustrates the potential of sentiment analysis of user comments in recommendation systems.     

Large-scale evaluation of splicing localization algorithms for web images

With the proliferation of smartphones and social media, journalistic practices are increasingly dependent on information and images contributed by local bystanders through Internet-based applications and platforms. Verifying the images produced by these sources is integral to forming accurate news reports, given that there is very little or no control over the type of user-contributed content, and hence, images found on the Web are always likely to be the result of image tampering. In particular, image splicing, i.e. the process of taking an area from one image and placing it in another is a typical such tampering practice, often used with the goal of misinforming or manipulating Internet users. Currently, the localization of splicing traces in images found on the Web is a challenging task. In this work, we present the first, to our knowledge, exhaustive evaluation of today’s state-of-the-art algorithms for splicing localization, that is, algorithms attempting to detect which pixels in an image have been tampered with as the result of such a forgery. As our aim is the application of splicing localization on images found on the Web and social media environments, we evaluate a large number of algorithms aimed at this problem on datasets that match this use case, while also evaluating algorithm robustness in the face of image degradation due to JPEG recompressions. We then extend our evaluations to a large dataset we formed by collecting real-world forgeries that have circulated the Web during the past years. We review the performance of the implemented algorithms and attempt to draw broader conclusions with respect to the robustness of splicing localization algorithms for application in Web environments, their current weaknesses, and the future of the field. Finally, we openly share the framework and the corresponding algorithm implementations to allow for further evaluations and experimentation.     

Exploring Social Annotations with the Application to Web Page Recommendation

Collaborative social annotation systems allow users to record and share their original keywords or tag attachments to Web resources such as Web pages, photos, or videos. These annotations are a method for organizing and labeling information. They have the potential to help users navigate the Web and locate the needed resources. However, since annotations are posted by users under no central control, there exist problems such as spam and synonymous annotations. To efficiently use annotation information to facilitate knowledge discovery from the Web, it is advantageous if we organize social annotations from semantic perspective and embed them into algorithms for knowledge discovery. This inspires the Web page recommendation with annotations, in which users and Web pages are clustered so that semantically similar items can be related. In this paper we propose four graphic models which cluster users, Web pages and annotations and recommend Web pages for given users by assigning items to the right cluster first. The algorithms are then compared to the classical collaborative filtering recommendation method on a real-world data set. Our result indicates that the graphic models provide better recommendation performance and are robust to fit for the real applications.     

Quality models for venue recommendation in location-based social network

With the rapid development of location-based social networks (LBSNs), increasing media data is ceaselessly uploaded by users. The multimedia data is often scattered and not informative and consequently they can not directly represent the semantics of each venue. Most of prior works leverage the user’ travelling histories to recommend new venues to users. However, these works often focus on the users’ travelling histories, while ignore the concepts or the popular levels of venues. In this paper, we proposed a quality model for venue recommendation by utilizing multimedia data to predict the interested level of each venue. First, we apply the graph cut method to generate the latent textual topics. Second, we leverage visual data from Flickr to train concept detectors to automatically label visual information. Third, the weighted bipartite matching algorithm is implemented to generate the venue multimedia topics by bridging the textual information and the visual information. Finally, we utilize the matching cost to predict the popular level of venue for recommendation. The experiments have been conducted on the cross-platform datasets. The results demonstrate the superiority of the proposed model.     

基于Swarm模型的微博用户影响力评价方法

微博作为一种重要的社交媒体,许多学者都对微博中用户的影响力进行研究,但大多数影响力的评价算法都是根据微博话题中用户的静态属性或微博话题发生后用户的行为特征对用户影响力进行评价。从用户的转发、评论和点赞三种行为入手,结合突现计算模型,提出一种基于Swarm模型的用户影响力排序算法,SMRank算法可以在微博话题发生的过程中对用户每个时间段的影响力进行计算,给出了一种计算微博话题用户影响力的新方法。通过使用真实的微博话题数据进行实验,结果表明提出的SMRank算法可以有效地发现微博话题中影响等级较大的用户,并能计算出不同用户不同时刻的影响力。     

基于JSP的网络视音频播放系统设计与实现

根据流媒体传输原理,在局域网的基础上模拟基于Web的视频和音频播放系统,实现用户信息管理、听音频、看视频、文件的添加、删除、修改、上传及搜索功能等,从而设计出符合现在人们需求的视音频播放系统,为网络时代的人们提供方便、快捷的视音频点播节目,提供更加人性化设置。     

Sockpuppet gang detection on social media sites

Users of social media sites can use more than one account. These identities have pseudo anonymous properties, and as such some users abuse multiple accounts to perform undesirable actions, such as posting false or misleading remarks comments that praise or defame the work of others. The detection of multiple user accounts that are controlled by an individual or organization is important. Herein, we define the problem as sockpuppet gang (SPG) detection. First, we analyze user sentiment orientation to topics based on emotional phrases extracted from their posted comments. Then we evaluate the similarity between sentiment orientations of user account pairs, and build a similar-orientation network (SON) where each vertex represents a user account on a social media site. In an SON, an edge exists only if the two user accounts have similar sentiment orientations to most topics. The boundary between detected SPGs may be indistinct, thus by analyzing account posting behavior features we propose a multiple random walk method to iteratively remeasure the weight of each edge. Finally, we adopt multiple community detection algorithms to detect SPGs in the network. User accounts in the same SPG are considered to be controlled by the same individual or organization. In our experiments on real world datasets, our method shows better performance than other contemporary methods.     

标签时态特征分析及其在标签预测中的应用

标签作为用户生成的对资源的描述,反映了资源的语义和用户的兴趣。由于Web资源的动态性,标签数据相应地表现出较为明显的时态特征,已有相关研究中标签的时态特征却很少受到关注。针对这方面的不足,对标签数据的时态特征以及基于时态特征的标签间语义关联进行分析,并提出发现标签时态特征的时间段划分准则;为了评价标签时态特征的价值,以经典的统计主题模型为基础,提出新的模型用于分析数据时态特征对所生成主题的影响,并将其用于标签预测。在多个数据集上的测试验证了标签数据的时态特性及其对提高标签预测性能的影响。     

A Unified Framework for Providing Recommendations in Social Tagging Systems Based on Ternary Semantic Analysis

Social Tagging is the process by which many users add metadata in the form of keywords, to annotate and categorize items (songs, pictures, Web links, products, etc.). Social tagging systems (STSs) can provide three different types of recommendations: They can recommend 1) tags to users, based on what tags other users have used for the same items, 2) items to users, based on tags they have in common with other similar users, and 3) users with common social interest, based on common tags on similar items. However, users may have different interests for an item, and items may have multiple facets. In contrast to the current recommendation algorithms, our approach develops a unified framework to model the three types of entities that exist in a social tagging system: users, items, and tags. These data are modeled by a 3-order tensor, on which multiway latent semantic analysis and dimensionality reduction is performed using both the Higher Order Singular Value Decomposition (HOSVD) method and the Kernel-SVD smoothing technique. We perform experimental comparison of the proposed method against state-of-the-art recommendation algorithms with two real data sets (Last.fm and BibSonomy). Our results show significant improvements in terms of effectiveness measured through recall/precision.