1,795 research outputs found
A TWITTER-INTEGRATED WEB SYSTEM TO AGGREGATE AND PROCESS EMERGENCY-RELATED DATA
A major challenge when encountering time-sensitive, information critical
emergencies is to source raw volunteered data from on-site public sources and
extract information which can enhance awareness on the emergency itself from a
geographical context. This research explores the use of Twitter in the emergency
domain by developing a Twitter-integrated web system capable of aggregating and
processing emergency-related tweet data. The objectives of the project are to collect
volunteered tweet data on emergencies by public citizen sources via the Twitter API,
process the data based on geo-location information and syntax into organized
informational entities relevant to an emergency, and subsequently deliver the
information on a map-like interface. The web system framework is targeted for use
by organizations which seek to transform volunteered emergency-related data
available on the Twitter platform into timely, useful emergency alerts which can
enhance situational awareness, and is intended to be accessible to the public through
a user-friendly web interface. Rapid Application Development (RAD) is the
methodology of choice for project development. The developed system has a system
usability scale score of 84.25, after results were tabulated from a usability survey on
20 respondents. Said system is best for use in emergencies where the transmission
timely, quantitative data is of paramount importance, and is a useful framework on
extracting and displaying useful emergency alerts with a geographical perspective
based on volunteered citizen Tweets. It is hoped that the project can ultimately
contribute to the existing domain of knowledge on social media-assisted emergency
applications
Measuring information credibility in social media using combination of user profile and message content dimensions
Information credibility in social media is becoming the most important part of information sharing in the society. The literatures have shown that there is no labeling information credibility based on user competencies and their posted topics. This study increases the information credibility by adding new 17 features for Twitter and 49 features for Facebook. In the first step, we perform a labeling process based on user competencies and their posted topic to classify the users into two groups, credible and not credible users, regarding their posted topics. These approaches are evaluated over ten thousand samples of real-field data obtained from Twitter and Facebook networks using classification of Naive Bayes (NB), Support Vector Machine (SVM), Logistic Regression (Logit) and J48 algorithm (J48). With the proposed new features, the credibility of information provided in social media is increasing significantly indicated by better accuracy compared to the existing technique for all classifiers
Weakly-supervised Fine-grained Event Recognition on Social Media Texts for Disaster Management
People increasingly use social media to report emergencies, seek help or
share information during disasters, which makes social networks an important
tool for disaster management. To meet these time-critical needs, we present a
weakly supervised approach for rapidly building high-quality classifiers that
label each individual Twitter message with fine-grained event categories. Most
importantly, we propose a novel method to create high-quality labeled data in a
timely manner that automatically clusters tweets containing an event keyword
and asks a domain expert to disambiguate event word senses and label clusters
quickly. In addition, to process extremely noisy and often rather short
user-generated messages, we enrich tweet representations using preceding
context tweets and reply tweets in building event recognition classifiers. The
evaluation on two hurricanes, Harvey and Florence, shows that using only 1-2
person-hours of human supervision, the rapidly trained weakly supervised
classifiers outperform supervised classifiers trained using more than ten
thousand annotated tweets created in over 50 person-hours.Comment: In Proceedings of the AAAI 2020 (AI for Social Impact Track). Link:
https://aaai.org/ojs/index.php/AAAI/article/view/539
Unsupervised Detection of Sub-events in Large Scale Disasters
Social media plays a major role during and after major natural disasters
(e.g., hurricanes, large-scale fires, etc.), as people ``on the ground'' post
useful information on what is actually happening. Given the large amounts of
posts, a major challenge is identifying the information that is useful and
actionable. Emergency responders are largely interested in finding out what
events are taking place so they can properly plan and deploy resources. In this
paper we address the problem of automatically identifying important sub-events
(within a large-scale emergency ``event'', such as a hurricane). In particular,
we present a novel, unsupervised learning framework to detect sub-events in
Tweets for retrospective crisis analysis. We first extract noun-verb pairs and
phrases from raw tweets as sub-event candidates. Then, we learn a semantic
embedding of extracted noun-verb pairs and phrases, and rank them against a
crisis-specific ontology. We filter out noisy and irrelevant information then
cluster the noun-verb pairs and phrases so that the top-ranked ones describe
the most important sub-events. Through quantitative experiments on two large
crisis data sets (Hurricane Harvey and the 2015 Nepal Earthquake), we
demonstrate the effectiveness of our approach over the state-of-the-art. Our
qualitative evaluation shows better performance compared to our baseline.Comment: AAAI-20 Social Impact Trac
Better Safe Than Sorry: An Adversarial Approach to Improve Social Bot Detection
The arm race between spambots and spambot-detectors is made of several cycles
(or generations): a new wave of spambots is created (and new spam is spread),
new spambot filters are derived and old spambots mutate (or evolve) to new
species. Recently, with the diffusion of the adversarial learning approach, a
new practice is emerging: to manipulate on purpose target samples in order to
make stronger detection models. Here, we manipulate generations of Twitter
social bots, to obtain - and study - their possible future evolutions, with the
aim of eventually deriving more effective detection techniques. In detail, we
propose and experiment with a novel genetic algorithm for the synthesis of
online accounts. The algorithm allows to create synthetic evolved versions of
current state-of-the-art social bots. Results demonstrate that synthetic bots
really escape current detection techniques. However, they give all the needed
elements to improve such techniques, making possible a proactive approach for
the design of social bot detection systems.Comment: This is the pre-final version of a paper accepted @ 11th ACM
Conference on Web Science, June 30-July 3, 2019, Boston, U
Multi-source Multimodal Data and Deep Learning for Disaster Response: A Systematic Review.
Mechanisms for sharing information in a disaster situation have drastically changed due to new technological innovations throughout the world. The use of social media applications and collaborative technologies for information sharing have become increasingly popular. With these advancements, the amount of data collected increases daily in different modalities, such as text, audio, video, and images. However, to date, practical Disaster Response (DR) activities are mostly depended on textual information, such as situation reports and email content, and the benefit of other media is often not realised. Deep Learning (DL) algorithms have recently demonstrated promising results in extracting knowledge from multiple modalities of data, but the use of DL approaches for DR tasks has thus far mostly been pursued in an academic context. This paper conducts a systematic review of 83 articles to identify the successes, current and future challenges, and opportunities in using DL for DR tasks. Our analysis is centred around the components of learning, a set of aspects that govern the application of Machine learning (ML) for a given problem domain. A flowchart and guidance for future research are developed as an outcome of the analysis to ensure the benefits of DL for DR activities are utilized.Publishe
An Evaluation Methodology of Named Entities Recognition in Spanish Language: ECU 911 Case Study
The importance of the gathered information in Integrated Security Services as ECU911 in Ecuador is evidenced in terms of its quality and availability in order to perform decision-making tasks. It is a priority to avoid the loss of relevant information such as event address, places references, names, etc. In this context it is present Named Entity Recognition (NER) analysis for discovering information into informal texts. Unlike structured corpus and labeled for NER analysis like CONLL2002 or ANCORA, informal texts generated from emergency call dialogues have a very wide linguistic variety; in addition, there is a strong tending to lose important information in their processing. A relevant aspect to considerate is the identification of texts that denotes entities such as the physical address where emergency events occurred. This study aims to extract the locations in which an emergency event has been issued. A set of experiments was performed with NER models based on Convolutional Neural Network (CNN). The performance of models was evaluated according to parameters such as training dataset size, dropout rate, location dictionary, and denoting location. An experimentation methodology was proposed, with it follows the next steps: i) Data preprocessing, ii) Dataset labeling, iii) Model structuring, and iv) Model evaluating. Results revealed that the performance of a model improves when having more training data, an adequate dropout rate to control overfitting problems, and a combination of a dictionary of locations and replacing words denoting entities
Identifying Crisis Response Communities in Online Social Networks for Compound Disasters: The Case of Hurricane Laura and Covid-19
Online social networks allow different agencies and the public to interact
and share the underlying risks and protective actions during major disasters.
This study revealed such crisis communication patterns during hurricane Laura
compounded by the COVID-19 pandemic. Laura was one of the strongest (Category
4) hurricanes on record to make landfall in Cameron, Louisiana. Using the
Application Programming Interface (API), this study utilizes large-scale social
media data obtained from Twitter through the recently released academic track
that provides complete and unbiased observations. The data captured publicly
available tweets shared by active Twitter users from the vulnerable areas
threatened by Laura. Online social networks were based on user influence
feature ( mentions or tags) that allows notifying other users while posting a
tweet. Using network science theories and advanced community detection
algorithms, the study split these networks into twenty-one components of
various sizes, the largest of which contained eight well-defined communities.
Several natural language processing techniques (i.e., word clouds, bigrams,
topic modeling) were applied to the tweets shared by the users in these
communities to observe their risk-taking or risk-averse behavior during a major
compounding crisis. Social media accounts of local news media, radio,
universities, and popular sports pages were among those who involved heavily
and interacted closely with local residents. In contrast, emergency management
and planning units in the area engaged less with the public. The findings of
this study provide novel insights into the design of efficient social media
communication guidelines to respond better in future disasters
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