基于传染病模型的社交网络舆情话题传播

针对传统模型难以真实地描述社交网络舆情话题传播过程,提出一种基于传染病模型的社交网络舆情话题传播模型。分析了社交网络舆情话题的传播特点,根据传染病动力学机制,将内部感染概率、外部感染概率、免疫概率以及直接免疫概率引入舆情话题传播过程中,构建了社交网络舆情话题传播模型,在Matlab 2012平台下采用Facebook数据集进行仿真测试。仿真实验结果表明,该模型可以准确描述社交网络中的话题传播行为特征,研究结果可以为社交网络舆论管理者提供有价值的参考意见。     

A time-varying propagation model of hot topic on BBS sites and Blog networks

Modeling the propagation of hot online topic is a preliminary requirement of predicting the trend of hot online topic. We propose a time-varying hot topic propagation model in online discussion context based upon the collective behavior of users who are in different social subgroups on blog networks and bulletin board system (BBS) sites. By analyzing the stability of the equilibrium of our model, we search for the threshold to be watershed of the trend of hot online topic and generalize about two theorems from the results of analysis, they exposit two sufficient conditions under which the trend of hot online topic will die out or remain uniformly weakly persistent. Furthermore, we propose methods to predict the trend of hot online topic on the strength of our model and theorems. For different motivation, we design two methods: Method (I) is mainly served as a way of theoretical research for predicting long trend of single-peak hot online topic by the thresholds of theorems; and for application, we design method (II) to predict the number of users writing or commenting upon article posts with respect to multi-peak hot online topic and single-peak one in the following two days with the help of Method (I). Experiments of two methods are performed on widely-discussed topics on the Sina Blog and the famous Liang Quan Qi Mei (LQQM) BBS and Xi’an Jiaotong University (BMY) BBS in China. The experimental results show that our methods predict the trend of hot online topic efficiently not only for theoretical motivation but also for applicable motivation, and reduce the computational complexity. Hence, our model can serve as basis for predicting trends in hot online topic propagation.     

网络热点话题传播的脉冲时序行为动力模型

微博、论坛等交互式网站上的热点话题是网络舆情的源头与集散地,早期发现与预测网络热点话题是舆情控制的关键。针对交互式网络热点话题,Yasuko Matsubara等人对信息传播的模式进行了建模,提出了SpikeM模型,该模型可以较好地反映信息传播的模式。但是针对热点话题呈现多峰的情况,该模型则无法拟合。且该模型假设针对某一事件,每个网络用户只能发布一次消息,这与实际情况不符。从实际情况出发（针对同一话题,网络用户可以多次发布消息）,提出了脉冲时序行为动力模型（PTSDM）。假设多次发布消息的用户数服从幂律分布,从用户行为的角度分析话题的特征,在模型中引入脉冲干扰,使模型更具随机性,更符合客观实际,从而可以拟合不同类型的热点话题。采用两个数据集作为测试样本,进行了实验,实验表明了所构建模型的有效性。     

基于概率推理模型的博客倾向性检索研究

近年来博客作为一种新兴的大众化新闻发布媒介越来越受到人们和业界的关注.博客之间通过互相引用、互相推荐形成一个巨大的博客空间.在博客空间中,人们既可以自由发表对现实生活各种问题的观点,表达自己的情感,也可以对市场上出现的新产品进行评论.准确检索出博客空间中人们对重要话题、热点事件的观点看法对市场调研、网络舆情发现与预警等应用有重要意义.博客倾向性检索的目标是检索出与给定查询既要主题相关又要有与该查询相关评论的博文.为实现该目标,把概率推理模型应用于博客倾向性检索中,提出一个基于概率推理模型的博客倾向性检索算法.该算法把主题相关性评分和倾向性评分合并到一个统一的概率推理理论模型,能够有效计算博文中出现的主题描述与查询的主题相关性,合理度量倾向性词描述查询主题的倾向性强弱,并融合二者分数形成最后整体评分.实验表明,该算法能够有效地识别博客空间中与给定查询相关的观点,获得较好的结果.     

Personalized recommendation of popular blog articles for mobile applications

Weblogs have emerged as a new communication and publication medium on the Internet for diffusing the latest useful information. Providing value-added mobile services, such as blog articles, is increasingly important to attract mobile users to mobile commerce, in order to benefit from the proliferation and convenience of using mobile devices to receive information any time and anywhere. However, there are a tremendous number of blog articles, and mobile users generally have difficulty in browsing weblogs owing to the limitations of mobile devices. Accordingly, providing mobile users with blog articles that suit their particular interests is an important issue. Very little research, however, has focused on this issue.In this work, we propose a novel Customized Content Service on a mobile device (m-CCS) to filter and push blog articles to mobile users. The m-CCS includes a novel forecasting approach to predict the latest popular blog topics based on the trend of time-sensitive popularity of weblogs. Mobile users may, however, have different interests regarding the latest popular blog topics. Thus, the m-CCS further analyzes the mobile users’ browsing logs to determine their interests, which are then combined with the latest popular blog topics to derive their preferred blog topics and articles. A novel hybrid approach is proposed to recommend blog articles by integrating personalized popularity of topic clusters, item-based collaborative filtering (CF) and attention degree (click times) of blog articles. The experiment result demonstrates that the m-CCS system can effectively recommend mobile users’ desired blog articles with respect to both popularity and personal interests.     

基于图聚类的汉越双语新闻话题发现

跨语言新闻话题发现是将互联网上报道相同事件的不同语言新闻进行自动归类,由于不同语言文本很难表示在同一特征空间下,对其共同话题的挖掘就比较困难。然而类似的新闻事件在不同语言文本表达上具有相同的新闻要素,这些要素之间关联能够体现出新闻事件的关联性,因此,针对汉越新闻话题发现问题,提出基于文档图聚类的汉越双语新闻话题发现方法。首先提取汉越新闻文本新闻要素,借助文本中要素相似度计算汉越文本相关度,构建汉越双语文本图模型,获得新闻文本相似度矩阵;然后,借助图模型中文本间的传播特点,采用随机游走算法对相似度矩阵进行调整,最后利用信息传递算法进行聚类。实验结果表明提出的方法取得了很好的效果。     

基于正负反馈的SEIR微博舆情传播模型

社交网络舆情已经成为社会舆情的主要阵地。针对传统模型难以描述社交网络舆情话题的真实传播过程,分析社交网络舆情话题的真实特点,补充加入社交网络中显著的水军和僵尸粉这2大显著特征,作为舆情话题传播中的正负反馈,分别对舆情话题的传播起到推动及抑制作用,构建带有正负反馈的社交网络舆情传播话题模型,提高舆情预测模型的准确率,得出正负反馈对舆情传播的影响力。     

Finding Diachronic Like‐Minded Users

User communities in social networks are usually identified by considering explicit structural social connections between users. While such communities can reveal important information about their members such as family or friendship ties and geographical proximity, just to name a few, they do not necessarily succeed at pulling like‐minded users that share the same interests together. Therefore, researchers have explored the topical similarity of social content to build like‐minded communities of users. In this article, following the topic‐based approaches, we are interested in identifying communities of users that share similar topical interests with similar temporal behavior. More specifically, we tackle the problem of identifying temporal (diachronic) topic‐based communities, i.e., communities of users who have a similar temporal inclination toward emerging topics. To do so, we utilize multivariate time series analysis to model the contributions of each user toward emerging topics. Further, our modeling is completely agnostic to the underlying topic detection method. We extract topics of interest by employing seminal topic detection methods; one graph‐based and two latent Dirichlet allocation‐based methods. Through our experiments on Twitter data, we demonstrate the effectiveness of our proposed temporal topic‐based community detection method in the context of news recommendation, user prediction, and document timestamp prediction applications, compared with the nontemporal as well as the state‐of‐the‐art temporal approaches.     

基于动态主题模型融合多维数据的微博社区发现算法

随着微博用户的不断增加,微博网络已经成为用户进行信息交流的平台.针对由于博文长度受限,传统的社区发现算法无法有效解决微博网络的稀疏性等问题,提出了DC-DTM算法.DC-DTM算法首先将微博网络映射为有向加权网络,网络中边的方向反映结点之间的关注关系,利用提出的DTM模型计算出结点之间的语义相似度,并将其作为节点间连边的权重.DTM模型是一种微博主题模型,该模型不仅能够挖掘博客的主题分布,而且能计算出某一主题中用户的影响力大小.其次,利用提出的复杂度低的标签传播算法WLPA进行微博网络的社区发现.该算法的初始化阶段将影响力大的用户结点作为初始结点,标签按照结点的影响力从大到小进行传播,克服了传统标签传播算法的逆流现象,提高了标签传播算法的稳定性.在真实数据上的实验表明,DTM模型能很好地对微博进行主题挖掘,DC-DTM算法能够有效地挖掘出微博网络的社区.     

面向微博话题的用户影响力分析算法

微博用户影响力分析作为社交网络分析的重要组成部分，一直受到研究人员的关注。针对现有研究工作分析用户行为时间性的不足和忽略用户与参与话题之间关联性等问题，提出了一种面向微博话题的用户影响力分析算法——基于话题和传播能力的用户排序（TSRank）算法。首先，基于微博话题分析用户转发行为时间性，进一步构建用户转发和用户博文转发两种话题转发关系网络，预测用户话题信息传播能力；然后，分析用户个人历史微博和背景话题微博文本内容，挖掘用户与背景话题之间的关联性；最后，综合考虑用户话题信息传播能力以及用户与背景话题间关联性计算微博用户影响力。爬取新浪微博真实话题数据进行实验，实验结果表明，话题关联度更高用户的话题转发量明显大于关联度很低的用户，引入用户转发行为时间性相比无转发时间性，TSRank算法的捕获率（CR）提高了18.7%，进一步与典型影响力分析算法WBRank、TwitterRank和PageRank相比，TSRank算法在准确率和召回率上分别提高了5.9%、8.7%、13.1%和6.7%、9.1%、14.2%，验证了TSRank算法的有效性。该研究成果对社交网络的社会属性、话题传播等理论研究以及好友推荐、舆情监控等应用研究具有支撑作用。     

Event extraction using behaviors of sentiment signals and burst structure in social media

Significant world events often cause the behavioral convergence of the expression of shared sentiment. This paper examines the use of the blogosphere as a framework to study user psychological behaviors, using their sentiment responses as a form of ‘sensor’ to infer real-world events of importance automatically. We formulate a novel temporal sentiment index function using quantitative measure of the valence value of bearing words in blog posts in which the set of affective bearing words is inspired from psychological research in emotion structure. The annual local minimum and maximum of the proposed sentiment signal function are utilized to extract significant events of the year and corresponding blog posts are further analyzed using topic modeling tools to understand their content. The paper then examines the correlation of topics discovered in relation to world news events reported by the mainstream news service provider, Cable News Network, and by using the Google search engine. Next, aiming at understanding sentiment at a finer granularity over time, we propose a stochastic burst detection model, extended from the work of Kleinberg, to work incrementally with stream data. The proposed model is then used to extract sentimental bursts occurring within a specific mood label (for example, a burst of observing ‘shocked’). The blog posts at those time indices are analyzed to extract topics, and these are compared to real-world news events. Our comprehensive set of experiments conducted on a large-scale set of 12 million posts from Livejournal shows that the proposed sentiment index function coincides well with significant world events while bursts in sentiment allow us to locate finer-grain external world events.     

改进在线词对主题模型的微博热点话题演化

话题演化分析是舆情监控的研究热点之一,面向微博热点话题进行演化分析,对于网络用户以及网络监管部门都有很重要的现实意义。针对在线词对主题模型（On-line Biterm Topic Model,OBTM）新旧主题混合、冗余词概率相对较高的问题,对OBTM进行改进,提出基于话题标签和先验参数的OBTM模型（Topic Labels and Prior Parameters OBTM,LPOBTM）。根据微博热点话题的话题标签,将微博文本集区分为含话题标签和不含话题标签的两类数据集,并设置不同的文档-主题先验参数;在前一时间片文档-主题概率分布的基础上,借鉴Sigmod函数对所有主题进行强度排名,从而优化当前时间片上主题-词分布的先验参数计算方法。实验结果表明,LPOBTM能够更准确地描述话题的内容演化情况,并且有更低的模型困惑度。     

基于多传递影响力的社交媒体谣言检测方法

社交媒体谣言检测是当前研究的热点问题,现有方法多数通过获取大量用户属性学习用户特征,但不适用于谣言的早期检测,忽略了用户之间的潜在关系对信息传播的影响。提出一种基于多传递影响力的谣言检测方法,根据源微博及其对应转发(评论)之间的关系构建文本信息传播图,并通过图卷积神经网络来捕获、学习文本信息的传播特征。利用文本信息和用户传播过程中的影响力,丰富可用于谣言检测早期的检测信息。将存在转发关系的用户构成用户影响力传播图,构建一种用户节点影响力学习方法,获取用户节点影响力,以增强用户特征信息。在此基础上,将文本特征与用户特征融合以进行谣言检测,从而提升检测效果。在3个真实社交媒体数据集上的实验结果表明,该方法在谣言自动检测以及早期检测的效果都有显著提升,与目前最好的基准方法相比,在微博、Twitter15、Twitter16数据集上的正确率分别提高了2.8%、6.9%和3.4%。     

基于在线Biterm主题模型的舆情新闻事件跟踪

舆情新闻事件跟踪,是舆情监控、热点分析、政策制定等研究和应用的重要基础。针对舆情新闻的稀疏性、敏感性、易演化性、次生性等特点,基于在线Biterm主题模型（online Biterm topic model,DBTM）,通过随机坍缩变分贝叶斯（stochastic collapsed variational Bayesian inference,SCVB0）算法更新参数,提出面向舆情新闻事件监控的主题模型MBTM(monitor Biterm topic model),利用该模型检测初期事件主题,跟踪后续新闻所属的主题。为了对存在关联关系的事件进行串联,进一步给出事件线索的概念,分别从主题层面和语义层面度量线索关联度,进而针对新闻事件主题生成事件线索。实验结果表明,MBTM模型在大多数指标上均优于OBTM等模型,验证了该方法的有效性和高效性。     

Social sentiment sensor: a visualization system for topic detection and topic sentiment analysis on microblog

As a new form of social media, microblogging provides platform sharing, wherein users can share their feelings and ideas on certain topics. Bursty topics from microblogs are the results of the emerging issues that instantly attract more followers and more attention online, which provide a unique opportunity to gauge the relation between expressed public sentiment and hot topics. This paper presents a Social Sentiment Sensor (SSS) system on Sina Weibo to detect daily hot topics and analyze the sentiment distributions toward these topics. SSS includes two main techniques, namely, hot topic detection and topic-oriented sentiment analysis. Hot topic detection aims to detect the most popular topics online based on the following steps, topic detection, topic clustering, and topic popularity ranking. We extracted topics from the hashtags using a hashtag filtering model because they can cover almost all the topics. Then, we cluster the topics that describe the same issue, and rank the topic clusters via their popularity to exploit the final hot topics. Topic-oriented sentiment analysis aims to analyze public opinions toward the hot topics. After retrieving the topic-related messages, we recognize sentiment for each message using a state-of-the-art SVM (Support Vector Machine) sentiment classifier. Then, we summarize the sentiments for the hot topic to achieve topic sentiment distribution. Based on the above framework and algorithms, SSS produces a real-time visualization system to monitor social sentiments, which is offering the public a new and timely perspective on the dynamics of the social topics.     

基于共现关系的多源主题融合模型

主题检测是互联网舆情分析任务中不可或缺的工作,在话题发现、热点话题等方面会遇到大量的不同种类的文本,它们有着不同的特性,却包含着相同的主题。有效地利用不同源的特性具有重要的科研和实践意义。大多数主题模型都是检测单一来源的文档,但媒体消息都是从多种平台进行传播,而且消息长度不一,不同平台都有其各自的属性,从而导致难以进行统一的舆情监控。为此,提出了一个基于共现关系的多源主题融合模型（Multi-source Topic Fusion Model,MTFM）,该模型将共现（同一内容在不同地方出现）纳入到多源主题融合模型中实现异类源的准确话题提取。实验结果表明,与当前用于不同源主题检测的经典模型相比较,MTFM提供了另一种挖掘主题的方法。     

基于突发词聚类的微博突发事件检测方法

微博突发事件检测是网络舆情分析的重要分支,近年来已受到国内外学者的广泛关注。分析用户行为特征,提出一种用户影响力计算方法,并将其与微博文本特征、传播特征相结合,提出词语突发度概念作为突发词的判定标准,进而抽取突发词集;引入凝聚式层次聚类算法,对突发词集进行聚类,并筛选出合适的突发词类簇用以描述突发事件,从而实现微博突发事件检测。通过实验检测,结果是正确率为63.64%,召回率为87.5%,F值为0.74,表明该方法可以在大量微博数据中有效检测到突发事件。     

特定话题传播网络中的意见领袖检测方法

针对中文微博目前已有的意见领袖识别模型存在的不足,提出一种特定话题转播网络中的意见领袖检测方法.识别模型通过转发关系建立信息传播网络,以用户自身权威值和转发用户的支持力来评价用户的影响力.通过对微博两周以来特定话题下意见领袖的检测实验,结果表明该方法能够有效地识别特定话题下的意见领袖.     

基于BBS的热点话题发现与态势预测技术的研究

网络论坛BBS是中国网民一个重要的信息传播渠道,而其中的热点话题自然就成为舆情调控和效果评估的首要目标。提出一个快速有效的用于挖掘网络论坛中热点话题并分析预测其发展态势的方法,利用统计的方法为同一版面下帖子的热度打分并排序,并使用相关的数学模型对热度较高的帖子的发展态势进行分析与预测。通过实验验证了该模型的可行性和有效性,为进一步研究复杂网络中热点话题的演化奠定了基础。     

Modeling collective blogging dynamics of popular incidental topics

An extended susceptible-infective (SI) epidemic model is presented in this paper to describe the collective blogging behavior on popular incidental topics. Our model has two major extensions over the classic SI model: in the new model, different blog writers get interested in a specific topic with different probabilities, while in a classic SI model, the infection probability of a disease between any two individuals is identical; the new model takes into consideration the impact of external mainstream media on blog writers, while in a classical SI model, spreading of diseases is merely based on personal contacts between individuals. The new model is capable of explaining the widely observed early burst and heavy tail of topic propagation velocity. The proposed model has a closed-form solution when the individual interest is of uniform distribution with the external influence assumed constant. We validate the proposed model using ten topics from two different data sets: Sina Blog and LiveJournal Blogspace, the results indicating that our model fits the topic propagation velocity and predicts the propagation trend very well.