42 research outputs found

    What Facebook Messages Told Us About How We Handled Disaster Management during the COVID-19 Pandemic?

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    As COVID-19 continues, social media platforms such as Facebook have become an increasingly important tool for communication and information sharing for public and government agencies. The generic disaster management cycle (mitigation, preparedness, response, and recovery) provides systematic guidance to the public and government agencies to respond to the crisis and suggest appropriate measures for different disaster stages. In this study, we examine various trending topics and themes during the COVID-19 outbreak. Using this generic disaster management cycle as our guiding framework, we examine news topics\u27 evolution during the COVID-19 pandemic on Facebook during each of the four phases. Guided Latent Dirichlet Allocation (Guided LDA) is used for topic modeling to identify topics and themes, and text network analytics is used to understand the connectedness of these news topics during each phase and their evolution

    Evidence Gap Maps as Critical Information Communication Devices for Evidence-based Public Policy

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    The public policy cycle requires increasingly the use of evidence by policy makers. Evidence Gap Maps (EGMs) are a relatively new methodology that helps identify, process, and visualize the vast amounts of studies representing a rich source of evidence for better policy making. This document performs a methodological review of EGMs and presents the development of a working integrated system that automates several critical steps of EGM creation by means of applied computational and statistical methods. Above all, the proposed system encompasses all major steps of EGM creation in one place, namely inclusion criteria determination, processing of information, analysis, and user-friendly communication of synthesized relevant evidence. This tool represents a critical milestone in the efforts of implementing cutting-edge computational methods in usable systems. The contribution of the document is two-fold. First, it presents the critical importance of EGMs in the public policy cycle; second, it justifies and explains the development of a usable tool that encompasses the methodological phases of creation of EGMs, while automating most time-consuming stages of the process. The overarching goal is the better and faster information communication to relevant actors like policy makers, thus promoting well-being through better and more efficient interventions based on more evidence-driven policy making.Comment: Working pape

    Iterative Seed Word Generation for Interactive Topic Modelling: a Mixed Text Processing and Qualitative Content Analysis Approach

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    Topic models have great potential for helping researchers and practitioners understand the electronic word of mouth (eWoM). This potential is thwarted by their purely unsupervised nature, which often leads to topics that are not entirely explainable. We develop a novel method to iteratively generate seed words to guide the interactive topic models. We assess the validity and applicability of the proposed method by investigating the critical phenomenon of Contact Tracing Mobile Applications (CTMAs) post-adoption during a time of the COVID-19 pandemic. The results show that constructs developed through our interactive topic modeling can capture primary research variables related to the phenomenon. Compared to existing topic modeling methods, our approach shows superior performance in explaining users’ satisfaction with CTMAs

    Basic tasks of sentiment analysis

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    Subjectivity detection is the task of identifying objective and subjective sentences. Objective sentences are those which do not exhibit any sentiment. So, it is desired for a sentiment analysis engine to find and separate the objective sentences for further analysis, e.g., polarity detection. In subjective sentences, opinions can often be expressed on one or multiple topics. Aspect extraction is a subtask of sentiment analysis that consists in identifying opinion targets in opinionated text, i.e., in detecting the specific aspects of a product or service the opinion holder is either praising or complaining about

    Topic Embeddings – A New Approach to Classify Very Short Documents Based on Predefined Topics

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    Traditional unsupervised topic modeling approaches like Latent Dirichlet Allocation (LDA) lack the ability to classify documents into a predefined set of topics. On the other hand, supervised methods require significant amounts of labeled data to perform well on such tasks. We develop a new unsupervised method based on word embeddings to classify documents into predefined topics. We evaluate the predictive performance of this novel approach and compare it to seeded LDA. We use a real-world dataset from online advertising, which is comprised of markedly short documents. Our results indicate the two methods may complement one another well, leading to remarkable sensitivity and precision scores of ensemble learners trained thereupon

    Topics, trends, and sentiments of Tweets about the COVID-19 pandemic: temporal infoveillance study

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    With restricted movements and stay-at-home orders due to COVID-19 pandemic, social media platforms like Twitter have become an outlet for users to express their concerns, opinions and feelings about the pandemic. Individuals, health agencies and governments are using Twitter to communicate about COVID-19. This research builds on the emergent stream of studies to examine COVID-19 related English tweets covering a time period from Jan 1, 2020 to May 9, 2020. We perform a temporal assessment and examine variations in the topics and sentiment-scores to uncover key trends. To examine key themes and topics from COVID-19 related English tweets posted by individuals, and to explore the trends and variations in how the COVID-19 related tweets, key topics and associated sentiments changed over a period of time before and after the disease was declared as pandemic. Combining data from two publicly available COVID-19 tweet datasets with our own search, we compiled a dataset of 13.9 million COVID-19 related English tweets made by individuals. We use Guided latent Dirichlet allocation (LDA) to infer themes and topics underlying the tweets, and use VADER sentiment analysis to compute sentiment scores and examine weekly trends for 17 weeks. Topic modelling yielded 26 topics, grouped into 10 broader themes underlying the COVID-19 tweets. 20.51% of tweets were about COVID-19's impact of economy and markets, followed by spread and growth in cases (15.45%), treatment and recovery (13.14%), impact on healthcare sector (11.40%), and governments' response (11.19%). Average compound sentiment scores were found to be negative throughout the time period of our examination for spread and growth of cases, symptoms, racism, source of the outbreak and political impacts of COVID-19. In contrast, we saw a reversal of sentiments from negative to positive for prevention, impact on economy and market, governments' response, impact on healthcare industry, treatment and recovery. Identification of dominant themes, topics, sentiments and changing trends about COVID-19 pandemic can help governments, healthcare agencies and policy makers to frame appropriate responses to prevent and control the spread of pandemic
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