Opinion Spam Research Articles

Credibility in social media: opinions, news, and health information—a survey

In the Social Web scenario, where large amounts of User Generated Content diffuse through Social Media, the risk of running into misinformation is not negligible. For this reason, assessing and mining the credibility of both sources of information and information itself constitute nowadays a fundamental issue. Credibility, also referred as believability, is a quality perceived by individuals, who are not always able to discern with their cognitive capacities genuine information from the fake one. For this reason, in the recent years several approaches have been proposed to automatically assess credibility in Social Media. Most of them are based on data‐driven models, i.e., they employ machine‐learning techniques to identify misinformation, but recently also model‐driven approaches are emerging, as well as graph‐based approaches focusing on credibility propagation. Since multiple social applications have been developed for different aims and in different contexts, several solutions have been considered to address the issue of credibility assessment in Social Media. Three of the main tasks facing this issue and considered in this article concern: (1) the detection of opinion spam in review sites, (2) the detection of fake news and spam in microblogging, and (3) the credibility assessment of online health information. Despite the high number of interesting solutions proposed in the literature to tackle the above three tasks, some issues remain unsolved; they mainly concern both the absence of predefined benchmarks and gold standard datasets, and the difficulty of collecting and mining large amount of data, which has not yet received the attention it deserves. WIREs Data Mining Knowl Discov 2017, 7:e1209. doi: 10.1002/widm.1209This article is categorized under: Algorithmic Development > Web Mining Application Areas > Science and Technology Technologies > Machine Learning

Detecting opinion spammer groups and spam targets through community discovery and sentiment analysis

Detecting opinion spammer groups and spam targets through community discovery and sentiment analysis

Impact of reviewer social interaction on online consumer review fraud detection

BackgroundOnline consumer reviews have become a baseline for new consumers to try out a business or a new product. The reviews provide a quick look into the application and experience of the business/product and market it to new customers. However, some businesses or reviewers use these reviews to spread fake information about the business/product. The fake information can be used to promote a relatively average product/business or can be used to malign their competition. This activity is known as reviewer fraud or opinion spam. The paper proposes a feature set, capturing the user social interaction behavior to identify fraud. The problem being solved is one of the characteristics that lead to fraud rather than detecting fraud.MethodsNeural network algorithm is used to evaluate the proposed feature set and compare it against the state-of-the-art feature sets in detecting fraud. The feature set considers the user’s social interaction on the Yelp platform to determine if the user is committing fraud. The neural network algorithm helps in comparing the feature set with other feature sets used to detect fraud. Any attempt to find the characteristics that lead to fraud has a prerequisite to be good enough to detect fraud as well.ResultsThe F1 score obtained using neural networks is on par with all the well-known methods for detecting fraud, a value of 0.95. The effectiveness of the feature set is in rivaling the other approaches to fraud detection.ConclusionsA user’s social interaction on a digital platform such as Yelp is equally important in evaluating the user as social interaction is in real life. The characteristics that lead to fraud can be intuitively captured. The characteristics such as number of friends, number of followers and the number of times the user has provided a review which was helpful to multiple people provide the neural network with a base to form a relationship between opinion fraud and social interaction characteristics.

텍스트 분석의 신뢰성 확보를 위한 스팸 데이터 식별 방안

최근 뉴스, 블로그, 소셜미디어 등을 통해 방대한 양의 비정형 텍스트 데이터가 쏟아져 나오고 있다. 이러한 비정형 텍스트 데이터는 풍부한 정보 및 의견을 거의 실시간으로 반영하고 있다는 측면에서 그 활용도가 매우 높아, 학계는 물론 산업계에서도 분석 수요가 증가하고 있다. 하지만 텍스트 데이터의 유용성이 증가함과 동시에 이러한 텍스트 데이터를 왜곡하여 특정 목적을 달성하려는 시도도 늘어나고 있다. 이러한 스팸성 텍스트 데이터의 증가는 방대한 정보 가운데 필요한 정보를 획득하는 일을 더욱 어렵게 만드는 것은 물론, 정보 자체 및 정보 제공 매체에 대한 신뢰도를 떨어뜨리는 현상을 초래하게 된다. 따라서 원본 데이터로부터 스팸성 데이터를 식별하여 제거함으로써, 정보의 신뢰성 및 분석 결과의 품질을 제고하기 위한 노력이 반드시 필요하다. 이러한 목적으로 스팸을 식별하기 위한 연구가 오피니언 스팸 탐지, 스팸 이메일 검출, 웹 스팸 탐지 등의 분야에서 매우 활발하게 수행되었다. 본 연구에서는 스팸 식별을 위한 기존의 연구 동향을 자세히 소개하고, 블로그 정보의 신뢰성 향상을 위한 방안 중 하나로 블로그의 스팸 태그를 식별하기 위한 방안을 제안한다. Recently, tremendous amounts of unstructured text data that is distributed through news, blogs, and social media has gained much attention from many researchers and practitioners as this data contains abundant information about various consumers' opinions. However, as the usefulness of text data is increasing, more and more attempts to gain profits by distorting text data maliciously or nonmaliciously are also increasing. This increase in spam text data not only burdens users who want to obtain useful information with a large amount of inappropriate information, but also damages the reliability of information and information providers. Therefore, efforts must be made to improve the reliability of information and the quality of analysis results by detecting and removing spam data in advance. For this purpose, many studies to detect spam have been actively conducted in areas such as opinion spam detection, spam e-mail detection, and web spam detection. In this study, we introduce core concepts and current research trends of spam detection and propose a methodology to detect the spam tag of a blog as one of the challenging attempts to improve the reliability of blog information.

Identifying Deceptive Opinion Spam using Aspect-based Emotions and Human Behavior Modeling

Identifying Deceptive Opinion Spam using Aspect-based Emotions and Human Behavior Modeling

Neural networks for deceptive opinion spam detection: An empirical study

The products reviews are increasingly used by individuals and organizations for purchase and business decisions. Driven by the desire of profit, spammers produce synthesized reviews to promote some products or demote competitors products. So deceptive opinion spam detection has attracted significant attention from both business and research communities in recent years. Existing approaches mainly focus on traditional discrete features, which are based on linguistic and psychological cues. However, these methods fail to encode the semantic meaning of a document from the discourse perspective, which limits the performance. In this work, we empirically explore a neural network model to learn document-level representation for detecting deceptive opinion spam. First, the model learns sentence representation with convolutional neural network. Then, sentence representations are combined using a gated recurrent neural network, which can model discourse information and yield a document vector. Finally, the document representations are directly used as features to identify deceptive opinion spam. Based on three domains datasets, the results on in-domain and cross-domain experiments show that our proposed method outperforms state-of-the-art methods.

크라우드소싱 기반 문장재구성 방법을 통한 의견 스팸 데이터셋 구축 및 평가

웹이 정보 교환의 주된 수단으로 사용되면서, 온라인 리뷰의 중요도가 증가하는 동시에 사용자의 올바른 의사결정을 저해하는 의견 스팸 이슈가 부각되고 있으며, 관련 연구가 활발하게 진행되고 있다. 하지만 분석 및 학습에 필요한 기준 데이터셋의 부족함과 한계점들은 관련 연구의 발전을 더디게 하고 있다. 본 논문에서는 사실 리뷰를 모사한 새로운 형태의 Paraphrased Opinion Spam(POS) 데이터셋을 소개한다. 우리는 실제 스패머들이 스팸을 작성할 때 실제 리뷰를 참고한다는 경향에 착안하여, 실제 리뷰어들이 작성한 리뷰를 의역하는 과정을 통하여 본문에 포함되어 있는 사실 정보와 경험을 담은 스팸 데이터셋을 생성하였다. 실험 결과, 새롭게 생성된 POS 데이터셋이 언어학적으로 실제 리뷰들과 유사하여 스팸분류 모델을 이용하여 분류 시 기존의 데이터셋들보다 더 분류하기 힘들다는 것을 발견했다. 또한 데이터의 학습량에 따라서 스팸 리뷰의 분류 정확도가 비례적으로 증가하는 것을 확인함으로써, 데이터의 양이 스팸 분류 모델 성능에 중요한 요소로 작용한다는 것을 확인할 수 있었다.

Detection of fake opinions using time series

Today's e-commerce is highly depended on increasingly growing online customers’ reviews posted in opinion sharing websites. This fact, unfortunately, has tempted spammers to target opinion sharing websites in order to promote and demote products. To date, different types of opinion spam detection methods have been proposed in order to provide reliable resources for customers, manufacturers and researchers. However, supervised approaches suffer from imbalance data due to scarcity of spam reviews in datasets, rating deviation based filtering systems are easily cheated by smart spammers, and content based methods are very expensive and majority of them have not been tested on real data hitherto.The aim of this paper is to propose a robust review spam detection system wherein the rating deviation, content based factors and activeness of reviewers are employed efficiently. To overcome the aforementioned drawbacks, all these factors are synthetically investigated in suspicious time intervals captured from time series of reviews by a pattern recognition technique. The proposed method could be a great asset in online spam filtering systems and could be used in data mining and knowledge discovery tasks as a standalone system to purify product review datasets. These systems can reap benefit from our method in terms of time efficiency and high accuracy. Empirical analyses on real dataset show that the proposed approach is able to successfully detect spam reviews. Comparison with two of the current common methods, indicates that our method is able to achieve higher detection accuracy (F-Score: 0.86) while removing the need for having specific fields of Meta data and reducing heavy computation required for investigation purposes.

Malicious practice of fake reviews: Experimental insight into the potential of contextual indicators in assisting consumers to detect deceptive opinion spam

Consumers often rely on experiences from other individuals shared online when making purchase decisions; however, the trustworthiness of consumers’ online opinions is jeopardized by fake reviews. Three experimental studies were conducted that included different potential detection support mechanisms to identify fake reviews. The results show that a self-protection prime and two of the three tested detection support mechanisms affect the source’s trustworthiness. This research contributes to the field of online interactions by highlighting the potential of contextual – instead of textual – indicators, such as third-party labels and social proof, which assist Internet users in their efforts to detect fake reviews.

Survey of review spam detection using machine learning techniques

Online reviews are often the primary factor in a customer’s decision to purchase a product or service, and are a valuable source of information that can be used to determine public opinion on these products or services. Because of their impact, manufacturers and retailers are highly concerned with customer feedback and reviews. Reliance on online reviews gives rise to the potential concern that wrongdoers may create false reviews to artificially promote or devalue products and services. This practice is known as Opinion (Review) Spam, where spammers manipulate and poison reviews (i.e., making fake, untruthful, or deceptive reviews) for profit or gain. Since not all online reviews are truthful and trustworthy, it is important to develop techniques for detecting review spam. By extracting meaningful features from the text using Natural Language Processing (NLP), it is possible to conduct review spam detection using various machine learning techniques. Additionally, reviewer information, apart from the text itself, can be used to aid in this process. In this paper, we survey the prominent machine learning techniques that have been proposed to solve the problem of review spam detection and the performance of different approaches for classification and detection of review spam. The majority of current research has focused on supervised learning methods, which require labeled data, a scarcity when it comes to online review spam. Research on methods for Big Data are of interest, since there are millions of online reviews, with many more being generated daily. To date, we have not found any papers that study the effects of Big Data analytics for review spam detection. The primary goal of this paper is to provide a strong and comprehensive comparative study of current research on detecting review spam using various machine learning techniques and to devise methodology for conducting further investigation.

Detection of opinion spam based on anomalous rating deviation

The publication of fake reviews by parties with vested interests has become a severe problem for consumers who use online product reviews in their decision making. To counter this problem a number of methods for detecting these fake reviews, termed opinion spam, have been proposed. However, to date, many of these methods focus on analysis of review text, making them unsuitable for many review systems where accompanying text is optional, or not possible. Moreover, these approaches are often computationally expensive, requiring extensive resources to handle text analysis over the scale of data typically involved.In this paper, we consider opinion spammers manipulation of average ratings for products, focusing on differences between spammer ratings and the majority opinion of honest reviewers. We propose a lightweight, effective method for detecting opinion spammers based on these differences. This method uses binomial regression to identify reviewers having an anomalous proportion of ratings that deviate from the majority opinion. Experiments on real-world and synthetic data show that our approach is able to successfully identify opinion spammers. Comparison with the current state-of-the-art approach, also based only on ratings, shows that our method is able to achieve similar detection accuracy while removing the need for assumptions regarding probabilities of spam and non-spam reviews and reducing the heavy computation required for learning.

Finding Deceptive Opinion Spam by Correcting the Mislabeled Instances

Assessing the trustworthiness of reviews is a key in natural language processing and computational linguistics. Previous work mainly focuses on some heuristic strategies or simple supervised learning methods, which limit the performance of this task. This paper presents a new approach, from the viewpoint of correcting the mislabeled instances, to find deceptive opinion spam. Partition a dataset into several subsets, construct a classifier set for each subset and select the best one to evaluate the whole dataset. Error variables are defined to compute the probability that the instances have been mislabeled. The mislabeled instances are corrected based on two threshold schemes, majority and non-objection. The results display significant improvements in our method in contrast to the existing baselines.