Analysis and Forecasting of Trending Topics in Online Media Streams

Among the vast information available on the web, social media streams capture what people currently pay attention to and how they feel about certain topics. Awareness of such trending topics plays a crucial role in multimedia systems such as trend aware recommendation and automatic vocabulary selection for video concept detection systems. Correctly utilizing trending topics requires a better understanding of their various characteristics in different social media streams. To this end, we present the first comprehensive study across three major online and social media streams, Twitter, Google, and Wikipedia, covering thousands of trending topics during an observation period of an entire year. Our results indicate that depending on one's requirements one does not necessarily have to turn to Twitter for information about current events and that some media streams strongly emphasize content of specific categories. As our second key contribution, we further present a novel approach for the challenging task of forecasting the life cycle of trending topics in the very moment they emerge. Our fully automated approach is based on a nearest neighbor forecasting technique exploiting our assumption that semantically similar topics exhibit similar behavior. We demonstrate on a large-scale dataset of Wikipedia page view statistics that forecasts by the proposed approach are about 9-48k views closer to the actual viewing statistics compared to baseline methods and achieve a mean average percentage error of 45-19% for time periods of up to 14 days.Comment: ACM Multimedia 201

Time Aware Knowledge Extraction for Microblog Summarization on Twitter

Microblogging services like Twitter and Facebook collect millions of user generated content every moment about trending news, occurring events, and so on. Nevertheless, it is really a nightmare to find information of interest through the huge amount of available posts that are often noise and redundant. In general, social media analytics services have caught increasing attention from both side research and industry. Specifically, the dynamic context of microblogging requires to manage not only meaning of information but also the evolution of knowledge over the timeline. This work defines Time Aware Knowledge Extraction (briefly TAKE) methodology that relies on temporal extension of Fuzzy Formal Concept Analysis. In particular, a microblog summarization algorithm has been defined filtering the concepts organized by TAKE in a time-dependent hierarchy. The algorithm addresses topic-based summarization on Twitter. Besides considering the timing of the concepts, another distinguish feature of the proposed microblog summarization framework is the possibility to have more or less detailed summary, according to the user's needs, with good levels of quality and completeness as highlighted in the experimental results.Comment: 33 pages, 10 figure

Near Real-Time Sentiment and Topic Analysis of Sport Events

Sport events’ media consumption patterns have started transitioning to a multi-screen paradigm, where, through multitasking, viewers are able to search for additional information about the event they are watching live, as well as contribute with their perspective of the event to other viewers. The audiovisual and multimedia industries, however, are failing to capitalize on this by not providing the sports’ teams and those in charge of the audiovisual production with insights on the final consumers perspective of sport events. As a result of this opportunity, this document focuses on presenting the development of a near real-time sentiment analysis tool and a near real-time topic analysis tool for the analysis of sports events’ related social media content that was published during the transmission of the respective events, thus enabling, in near real-time, the understanding of the sentiment of the viewers and the topics being discussed through each event.Os padrões de consumo de media, têm vindo a mudar para um paradigma de ecrãs múltiplos, onde, através de multitasking, os telespetadores podem pesquisar informações adicionais sobre o evento que estão a assistir, bem como partilhar a sua perspetiva do evento. As indústrias do setor audiovisual e multimédia, no entanto, não estão a aproveitar esta oportunidade, falhando em fornecer às equipas desportivas e aos responsáveis pela produção audiovisual uma visão sobre a perspetiva dos consumidores finais dos eventos desportivos. Como resultado desta oportunidade, este documento foca-se em apresentar o desenvolvimento de uma ferramenta de análise de sentimento e uma ferramenta de análise de tópicos para a análise, em perto de tempo real, de conteúdo das redes sociais relacionado com eventos esportivos e publicado durante a transmissão dos respetivos eventos, permitindo assim, em perto de tempo real, perceber o sentimento dos espectadores e os tópicos mais falados durante cada evento

Large-Scale Mapping of Human Activity using Geo-Tagged Videos

This paper is the first work to perform spatio-temporal mapping of human activity using the visual content of geo-tagged videos. We utilize a recent deep-learning based video analysis framework, termed hidden two-stream networks, to recognize a range of activities in YouTube videos. This framework is efficient and can run in real time or faster which is important for recognizing events as they occur in streaming video or for reducing latency in analyzing already captured video. This is, in turn, important for using video in smart-city applications. We perform a series of experiments to show our approach is able to accurately map activities both spatially and temporally. We also demonstrate the advantages of using the visual content over the tags/titles.Comment: Accepted at ACM SIGSPATIAL 201

Semantics-Space-Time Cube. A Conceptual Framework for Systematic Analysis of Texts in Space and Time

We propose an approach to analyzing data in which texts are associated with spatial and temporal references with the aim to understand how the text semantics vary over space and time. To represent the semantics, we apply probabilistic topic modeling. After extracting a set of topics and representing the texts by vectors of topic weights, we aggregate the data into a data cube with the dimensions corresponding to the set of topics, the set of spatial locations (e.g., regions), and the time divided into suitable intervals according to the scale of the planned analysis. Each cube cell corresponds to a combination (topic, location, time interval) and contains aggregate measures characterizing the subset of the texts concerning this topic and having the spatial and temporal references within these location and interval. Based on this structure, we systematically describe the space of analysis tasks on exploring the interrelationships among the three heterogeneous information facets, semantics, space, and time. We introduce the operations of projecting and slicing the cube, which are used to decompose complex tasks into simpler subtasks. We then present a design of a visual analytics system intended to support these subtasks. To reduce the complexity of the user interface, we apply the principles of structural, visual, and operational uniformity while respecting the specific properties of each facet. The aggregated data are represented in three parallel views corresponding to the three facets and providing different complementary perspectives on the data. The views have similar look-and-feel to the extent allowed by the facet specifics. Uniform interactive operations applicable to any view support establishing links between the facets. The uniformity principle is also applied in supporting the projecting and slicing operations on the data cube. We evaluate the feasibility and utility of the approach by applying it in two analysis scenarios using geolocated social media data for studying people's reactions to social and natural events of different spatial and temporal scales

Spatio-temporal distribution analysis of brand interest in social networks

Social Networks applications such as Facebook and Twitter became part of many people’s lives and are used daily by millions of users. In such platforms, users share their emotions, opinions, experiences, and thoughts. Twitter, in particular, is used to discuss diverse topics, including brands, their products and services. In this thesis, we analyse how brand interest is reflected on Twitter and how this platform can be used to monitor what people say about specific brands, as an indicator of brand interest. Brand interest can be defined as the level of interest one has in a brand, and the level of curiosity one has to learn more about a brand. For this work, the volume of tweets is used as a measure of brand interest. Our methodology is based on time, location, and the number of brand-related tweets to perform a spatio-temporal analysis. Additionally, we propose a framework for discovering latent patterns (topics) from a large dataset of grouped short messages to analyse brand interest, using Twitter as a data source. We applied a well-known Text Mining technique called Topic Modelling, which is an unsupervised learning technique used when dealing with text data, useful to uncover topics in a collection of documents. This technique provides a convenient way to retrieve information from unstructured text. Topic Modelling tasks have been applied to track events/trends and uncover topics in domains such as academic, public health, marketing, and so forth. The framework consists of training LDA (Latent Dirichlet Allocation) topic models on aggregated tweets, and then applying the model on different documents, also composed by grouped Twitter posts. Furthermore, we describe a set of pre-processing tasks that helped to improve the performance of topic models, enabling us to obtain a better output, thus performing a better analysis of it. The experiments demonstrated that Topic Modelling can successfully track people’s discussions on Social Networks even in massive datasets such as the one used in the current work, and capture those topics spiked by real-life eventsActualmente, plataformas como Twitter e Facebook fazem parte do dia-a-dia de muitas pessoas e são usadas por milhões de utilizadores. Nestas plataformas, denominadas Redes Sociais, os utilizadores partilham informações incluindo opiniões, sentimentos, experiências e pensamentos. A plataforma Twitter, em particular, e usada para partilhar diversos tópicos, que podem incluir dicussões sobre marcas, seus produtos e/ou serviços. O presente estudo analisa como o interesse numa marca e reflectido na Rede Social Twitter e apresenta uma metodologia que permite utilizar o Twitter como fonte de informação para monitorizar o que os utilizadores dizem acerca de determinadas marcas. O interesse numa marca pode ser definido como o nível de interesse que um indivíduo tem por uma marca, e o nível de curiosidade que um indivíduo tem e que o leva a aprender mais acerca dessa marca. Neste estudo, o número de tweets publicados e usado para medir o interesse nas marcas escolhidas. A metodologia seguida baseia-se na data em que o tweet foi publicado, localização, e número de publicações, para efectuar uma análise espacio-temporal. Adicionalmente, apresenta-se uma framework que possibilita a exploração de um vasto conjunto de dados, com o objectivo de revelar padrões latentes, bem como analisar o interesse nas marcas seleccionadas, usando o Twitter como fonte dados. Para o efeito, aplicou-se Topic Modelling, uma técnica de Text Mining bastante utilizada para descobrir tópicos em texto não estruturado. Algoritmos de Topic Modelling têm sido amplamente utilizados para monitorizar eventos e tendências e descobrir tópicos em áreas como educação, marketing, saúde, entre outras. A framework consiste em treinar o modelo de tópicos LDA (Latent Dirichlet Allocation) usando tweets agrupados (considerando determinado critério) e posteriormente aplicar o modelo treinado noutro conjunto de tweets agrupados (considerando outro critério). Descreve-se um conjunto de tarefas de pré-processamento dos dados que ajudaram a melhorar o desempenho dos modelos, a obter melhor resultados e, consequentemente, a efectuar uma melhor análise. As experiências revelam que atravês de Topic Modelling e possível rastrear dicussões de utilizadores de Redes Sociais durante um longo período de tempo, e capturar alterações relacionadas com acontecimentos reais

Word-forest Visualization of Discussed Topics in Social Media Comments

It becomes a norm for many organizations to use social network as a platform for internal and external communication means. Due to its extensive usage, most large organizations recognize the importance of capturing disseminated information across the social networks for the benefit of their internal perusal. However, managing and keeping track of all the information which are hidden in the piles of comments are hard to deal with. This paper presents a system that can extract, analyze and visualize information from the comments. As for the case study, Facebook is chosen due to its ability to allow people to comment freely and repetitively. The comments were extracted from selected post in Facebook using its API. The relationship between the words inside the comments will then be determined by using relationship table. Then, a visualization technique, word-forest, is used to visualize the relation between the prepared table. The prototype is tested by using selected posts in specific Facebook accounts. The result shows that users can quickly get overviews on the topics that have been discussed without having to go through all the comments on the Facebook. The system has great potential to be further explored as one of the means to get internal and external workers or public perception unobtrusively at real-time and real-life setting