Extracting City Traffic Events from Social Streams

TitleExtracting City Traffic Events from Social Streams
Publication TypeJournal Article
Year of Publication2015
AuthorsPramod Anantharam, Payam Barnaghi, Krishnaprasad Thirunarayan, Amit Sheth
JournalACM Transactions on Intelligent Systems and Technology
Date Published08/2015
KeywordsCitizen sensing, city events, event extraction, Knowledge Base, open street maps, physical-cyber-social systems, smart cities, tweets

Cities are composed of complex systems with physical, cyber, and social components. Current works on extracting and understanding city events mainly rely on technology enabled infrastructure to observe and record events. In this work, we propose an approach to leverage citizen observations of various city systems and services such as traffic, public transport, water supply, weather, sewage, and public safety as a source of city events. We investigate the feasibility of using such textual streams for extracting city events from annotated text. We formalize the problem of annotating social streams such as microblogs as a sequence labeling problem. We present a novel training data creation process for training sequence labeling models. Our automatic training data creation process utilizes instance level domain knowledge (e.g., locations in a city, possible event terms). We compare this automated annotation process to a state-of-the-art tool that needs manually created training data and show that it has comparable performance in annotation tasks. An aggregation algorithm is then presented for event extraction from annotated text. We carry out a comprehensive evaluation of the event annotation and event extraction on a real-world dataset consisting of event reports and tweets collected over four months from San Francisco Bay Area. The evaluation results are promising and provide insights into the utility of social stream for extracting city events.