A joint model for analyzing topic and sentiment dynamics from large-scale online news

Many of today’s online news websites and aggregator apps have enabled users to publish their opinions without respect to time and place. Existing works on topic-based sentiment analysis of product reviews cannot be applied to online news directly because of the following two reasons: (1) The dynamic nature of news streams require the topic and sentiment analysis model also to be dynamically updated. (2) The user interactions among news comments can easily lead to inaccurate topic extraction and sentiment classification. In this paper, we propose a novel probabilistic generative model (DTSA) to extract topics and the specified sentiments from news streams and analyze their evolution over time simultaneously. In DTSA, three different timescale models are studied to account for the historical dependencies of sentiment-topic word distributions at current epoch, continuous, skip and multiple timescale models. Additionally, we further consider the links among news comments to avoid the error caused by user interactions. In order to mine more interpretable topics, a Conditional Random Fields (CRF) model is adopted to label a set of meaningful phrases for augmenting the bag-of-word features. Finally, we derive distributed online inference procedures to update the model with newly arrived data and show the effectiveness of our proposed model on real-world data sets.     

融合情感过滤的突发事件检测方法

针对微博等自媒体平台中,突发事件存在的突发性、多爆发点,给突发事件检测带来困难,提出一种整合用户情感过滤的突发事件检测方法.该方法首先将话题映射为层次模型,以时序驱动的方式动态调整模型特征,探测信息新话题.以此为基础分析用户对该话题所持有的情感态度,依据用户的情感态度将话题划分为正面和负面情感倾向两类,并将饱含负面情感倾向的话题视为突发话题.实验证明,无论是准确率还是查全率所提方法均比baseline提高约10%以上.     

Sentiment analysis from Customer-generated online videos on product review using topic modeling and Multi-attention BLSTM

With the popularity of social websites and mobile applications including Instagram, YouTube, TikTok, etc., online videos shared by customers presenting their thoughts and reviews on products are posted daily in increasing numbers. Such online videos containing Voice of Customer (VOC) are precious for product designers or managers to capture customer sentiment and understand customer preference. For this purpose, we propose a novel method for analyzing customer sentiment from online videos on product review. Firstly, latent Dirichlet allocation (LDA) modeling is applied to identify the topics from the online videos after data preprocessing. Then sentiment polarity corresponding to each topic of each speaker in videos can be identified using our newly designed multi-attention bi-directional LSTM (BLSTM(MA)), which can better mine complex relationships among a speaker’s sentiments on different topics. This paper is of great practical value for company managers and researchers to better understand a large number of customer opinions on specific products. To explain the application of this method and prove its effectiveness, two cases respectively on smartphones and several published datasets are developed finally.     

Online web video topic detection and tracking with semi-supervised learning

With the pervasiveness of online social media and rapid growth of web data, a large amount of multi-media data is available online. However, how to organize them for facilitating users’ experience and government supervision remains a problem yet to be seriously investigated. Topic detection and tracking, which has been a hot research topic for decades, could cluster web videos into different topics according to their semantic content. However, how to online discover topic and track them from web videos and images has not been fully discussed. In this paper, we formulate topic detection and tracking as an online tracking, detection and learning problem. First, by learning from historical data including labeled data and plenty of unlabeled data using semi-supervised multi-class multi-feature method, we obtain a topic tracker which could also discover novel topics from the new stream data. Second, when new data arrives, an online updating method is developed to make topic tracker adaptable to the evolution of the stream data. We conduct experiments on public dataset to evaluate the performance of the proposed method and the results demonstrate its effectiveness for topic detection and tracking.     

Exploring the effect of user engagement in online brand communities: Evidence from Twitter

Social media such as forums, blogs and microblogs has been increasingly used for public information sharing and opinions exchange nowadays. It has changed the way how online community interacts and somehow has led to a new trend of engagement for online retailers especially on microblogging websites such as Twitter. In this study, we investigated the impact of online retailers' engagement with the online brand communities on users' perception of brand image and service. Firstly, we analysed the overall sentiment trends of different brands and the patterns of engagement between companies and customers using the collected tweets posted on a popular social media platform, Twitter. Then, we studied how different types of engagements affect customer sentiments. Our analysis shows that engagement has an effect on sentiments that associate with brand image, perception and customer service of the online retailers. Our findings indicate that the level, length, type and attitude of retailers' engagement with social media users have a significant impact on their sentiments. Based on our results, we derived several important managerial and practical implications.     

QuestionHolic: Hot topic discovery and trend analysis in community question answering systems

Community question answering (CQA) has recently become a popular social media where users can post questions on any topic of interest and get answers from enthusiasts. The variation of topics in questions and answers indicate the change of users’ interests over time. It can help users focus on the most popular products or events and track their changes by exploiting hot topics and analyzing the trend of a specific topic. In this paper, we present a hot topic detection and trend analysis system to capture hot topics in a CQA system and track their evolutions over time. Our system consists of hot term extraction, question clustering and trend analysis. Experimental results using datasets from Yahoo! Answers show that our system can discover meaningful hot topics. We also show that the evolution of topics over time can be accurately exploited by trend graphing.     

A probabilistic method for emerging topic tracking in Microblog stream

Microblog is a popular and open platform for discovering and sharing the latest news about social issues and daily life. The quickly-updated microblog streams make it urgent to develop an effective tool to monitor such streams. Emerging topic tracking is one of such tools to reveal what new events are attracting the most online attention at present. However, due to the fast changing, high noise and short length of the microblog feeds, two challenges should be addressed in emerging topic tracking. One is the problem of detecting emerging topics early, long before they become hot, and the other is how to effectively monitor evolving topics over time. In this study, we propose a novel emerging topics tracking method, which aligns emerging word detection from temporal perspective with coherent topic mining from spatial perspective. Specifically, we first design a metric to estimate word novelty and fading based on local weighted linear regression (LWLR), which can highlight the word novelty of expressing an emerging topic and suppress the word novelty of expressing an existing topic. We then track emerging topics by leveraging topic novelty and fading probabilities, which are learnt by designing and solving an optimization problem. We evaluate our method on a microblog stream containing over one million feeds. Experimental results show the promising performance of the proposed method in detecting emerging topic and tracking topic evolution over time on both effectiveness and efficiency.     

Multi-granular document-level sentiment topic analysis for online reviews

Applied Intelligence - It is key to identify both sentiment and topic for well understanding and managing social media data such as online reviews and microblogs. This paper studies a robust and...     

基于动态主题情感混合模型的微博主题情感演化分析方法

针对现有模型无法进行微博主题情感演化分析的问题,提出一种基于主题情感混合模型(TSCM)和情感周期性理论的主题情感演化模型——动态主题情感混合模型(DTSCM)。DTSCM通过捕获不同时间片中微博消息集的主题和情感,追踪不同时间片内主题与情感的变化趋势,获得主题情感演化图,从而实现主题和情感的演化分析。真实微博数据集上的实验结果表明,与当前优秀代表算法JST(Joint Sentiment/Topic)、S-LDA(Sentiment-Latent Dirichlet Allocation)和DPLDA(Dependency Phrases-Latent Dirichlet Allocation)相比,该方法的情感分类准确率分别提高了3.01%、4.33%和8.75%,并且可以获得主题情感演化图。这表明该方法具有更高的情感分类准确率并且可以进行微博主题情感演化分析,为舆情分析等应用提供了较好的帮助。     

Joint sentiment/topic modeling on text data using a boosted restricted Boltzmann Machine

Recently by the development of the Internet and the Web, different types of social media such as web blogs become an immense source of text data. Through the processing of these data, it is possible to discover practical information about different topics, individual’s opinions and a thorough understanding of the society. Therefore, applying models which can automatically extract the subjective information from documents would be efficient and helpful. Topic modeling methods and sentiment analysis are the raised topics in natural language processing and text mining fields. In this paper a new structure for joint sentiment-topic modeling based on a Restricted Boltzmann Machine (RBM) which is a type of neural networks is proposed. By modifying the structure of RBM as well as appending a layer which is analogous to sentiment of text data to it, we propose a generative structure for joint sentiment topic modeling based on neural networks. The proposed method is supervised and trained by the Contrastive Divergence algorithm. The new attached layer in the proposed model is a layer with the multinomial probability distribution which can be used in text data sentiment classification or any other supervised application. The proposed model is compared with existing models in the experiments such as evaluating as a generative model, sentiment classification, information retrieval and the corresponding results demonstrate the efficiency of the method.

     

中文博客主题情感句自动抽取研究

博客作为一种大众化的信息及文化载体被越来越多的人所接受,博客信息的情感分析也逐渐成为了信息挖掘领域的热点。目前,在研究情感分析时,多是通过计算词汇的倾向性来完成的。由于并不是所有的带有情感色彩的词汇都是主题相关的,因此,以词为粒度的情感分析存在一定的缺陷。为了解决这一问题,试图从句子层面进行分析,主要研究了与之相关的主题情感句的自动提取问题。为了有效地提取主题相关情感句,设计了一个新颖的基于二元切分的提取算法来获取主题词,然后利用TFIDF算法获取更多的次要主题词,并利用这些主题词重组了那些包含主题词的原始句。因此,如果主题情感句存在的话,那么它一定在这些重组的主题句集合中,只要对该重组句集合进行分析、提取,便能得到主题情感句。最后,利用CRFs将主题句提取问题有效转化为了中文chunking问题,并在抽取实验中取得了很好的结果。     

Exploring sentiment parsing of microblogging texts for opinion polling on chinese public figures

Microblogging websites such as twitter and Sina Weibo have attracted many users to share their experiences and express their opinions on a variety of topics, making them ideal platforms on which to conduct electronic opinion polls on products, services and public figures. However, conventional sentiment analysis methods for microblogging messages may not meet the demands of opinion polls for public figures. Therefore, in this study, we focus mainly on the problem of sentiment analysis for opinion polling on Chinese public figures. We propose a sentiment parsing-based architecture, which represents and labels opinion targets and their corresponding sentiments jointly to avoid the mismatching of them, for opinion poll of public figures using microblogs. Furthermore, we formulate sentiment parsing of microblogging sentences as a sequence labeling problem and adapt different Recurrent Neural Network (RNN) models to train and infer the model. Our experimental results demonstrate that the proposed sentiment parsing-based methods achieve better performance than conventional sentiment score-based methods in opinion polling on public figures using microblogs.     

基于社交关系的微博主题情感挖掘

微博情感分析是社交媒体挖掘中的重要任务之一,在个性化推荐、舆情分析等方面具有重要的理论和应用价值.挖掘性能良好且可同步进行文档主题分析与情感分析的主题情感模型近来在以微博为代表的社交媒体情感分析中备受关注。然而,绝大多数现有主题情感模型都简单地假设不同微博的情感极性是互相独立,这与微博生态的现实状况不相一致的,从而导致这些模型无法对用户的真实情感进行有效建模。基于此,本文综合考虑了微博用户相互关联的事实,提出基于LDA和微博用户关系的主题情感模型SRTSM,该模型在LDA中加入情感层与微博用户关系参数,利用微博用户关系与微博主题学习微博的情感极性。新浪微博真实数据集上的大量实验表明,与代表性算法JST、Sentiment-LDA与DPLDA相比较,SRTSM模型能对用户真实情感与讨论主题进行更加有效的分析建模.     

基于弹幕情感分析和主题模型的视频推荐算法

针对互联网上大量自制视频缺少用户评分、推荐准确率不高的问题,提出一种融合弹幕情感分析和主题模型的视频推荐算法（VRDSA）。首先,对视频的弹幕评论进行情感分析,得到视频的情感向量,之后基于情感向量计算视频之间的情感相似度;同时,基于视频的标签建立主题模型来得到视频标签的主题分布,并使用主题分布计算视频之间的主题相似度;接着,对视频的情感相似度和主题相似度进行融合得到视频间的综合相似度;然后,结合视频间的综合相似度和用户的历史记录得到用户对视频的偏好度;同时通过视频的点赞量、弹幕量、收藏数等用户互动指标对视频的大众认可度进行量化,并结合用户历史记录计算出视频的综合认可度;最后,基于用户对视频的偏好度和视频的综合认可度预测用户对视频的认可度,并生成个性化推荐列表来完成视频的推荐。实验结果表明,与融合协同过滤和主题模型的弹幕视频推荐算法（DRCFT）以及嵌入LDA主题模型的协同过滤算法（ULR-itemCF）相比,所提算法推荐的准确率平均提高了17.1%,召回率平均提高了22.9%,F值平均提高了22.2%。所提算法对弹幕进行情感分析,并融合主题模型,以此来完成对视频的推荐,并且充分挖掘了弹幕数据的情感性,使得推荐结果更加准确。     

A comparative empirical study on social media sentiment analysis over various genres and languages

People express their opinions about things like products, celebrities and services using social media channels. The analysis of these textual contents for sentiments is a gold mine for marketing experts as well as for research in humanities, thus automatic sentiment analysis is a popular area of applied artificial intelligence. The chief objective of this paper is to investigate automatic sentiment analysis on social media contents over various text sources and languages. The comparative findings of the investigation may give useful insights to artificial intelligence researchers who develop sentiment analyzers for a new textual source. To achieve this, we describe supervised machine learning based systems which perform sentiment analysis and we comparatively evaluate them on seven publicly available English and Hungarian databases, which contain text documents taken from Twitter and product review sites. We discuss the differences among these text genres and languages in terms of document- and target-level sentiment analysis.     

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.     

基于主题情感句的汉语评论文倾向性分析*

提出一种基于主题情感句的汉语评论文倾向性分析方法.根据评论文的特点,采用一种基于n元词语匹配的方法识别主题,通过对比与主题的语义相似度和进行主客观分类抽取出候选主题情感句,计算其中相似度最高的若干个句子的情感倾向,将其平均值作为评论文的整体倾向.基于主题情感句的评论文倾向性分析方法避免了进行篇章结构分析,排除了与主题无...     

Discovering public sentiment in social media for predicting stock movement of publicly listed companies

The popularity of many social media sites has prompted both academic and practical research on the possibility of mining social media data for the analysis of public sentiment. Studies have suggested that public emotions shown through Twitter could be well correlated with the Dow Jones Industrial Average. However, it remains unclear how public sentiment, as reflected on social media, can be used to predict stock price movement of a particular publicly-listed company. In this study, we attempt to fill this research void by proposing a technique, called SMeDA-SA, to mine Twitter data for sentiment analysis and then predict the stock movement of specific listed companies. For the purpose of experimentation, we collected 200 million tweets that mentioned one or more of 30 companies that were listed in NASDAQ or the New York Stock Exchange. SMeDA-SA performs its task by first extracting ambiguous textual messages from these tweets to create a list of words that reflects public sentiment. SMeDA-SA then made use of a data mining algorithm to expand the word list by adding emotional phrases so as to better classify sentiments in the tweets. With SMeDA-SA, we discover that the stock movement of many companies can be predicted rather accurately with an average accuracy over 70%. This paper describes how SMeDA-SA can be used to mine social media date for sentiments. It also presents the key implications of our study.     

结合互信息和主题模型的微博话题发现方法

为了解决短文本信息流的特征稀疏性对热点话题发现带来的挑战,提出了结合词语互信息和概率主题模型的微博热点话题发现方法。通过建立词共现矩阵并应用对称非负矩阵分解算法获取词项-主题矩阵,再利用概率潜在语义分析模型进行主题发现,最终通过定义微博热度分析和排序,有效地支持微博热点话题发现。实验表明,此方法能有效地进行话题聚类并检测出热点话题。     

Riding the tide of sentiment change: sentiment analysis with evolving online reviews

The last decade has seen a rapid growth in the volume of online reviews. A great deal of research has been done in the area of opinion mining, aiming at analyzing the sentiments expressed in those reviews towards products and services. Most of the such work focuses on mining opinions from a collection of reviews posted during a particular period, and does not consider the change in sentiments when the collection of reviews evolve over time. In this paper, we fill in this gap, and study the problem of developing adaptive sentiment analysis models for online reviews. Given the success of latent semantic modeling techniques, we propose two adaptive methods to capture the evolving sentiments. As a case study, we also investigate the possibility of using the extracted adaptive patterns for sales prediction. Our proposal is evaluated on an IMDB dataset consisting of reviews of selected movies and their box office revenues. Experimental results show that the adaptive methods can capture sentiment changes arising from newly available reviews, which helps greatly improve the prediction accuracy.