• A machine-learning approach to negation and speculation detection for sentiment analysis

      Cruz, Noa P.; Taboada, Maite; Mitkov, Ruslan; Department of Information Technology; University of Huelva; Huelva Spain; Department of Linguistics; Simon Fraser University; Vancouver Canada; Research Institute for Information and Language Processing; University of Wolverhampton; Wolverhampton UK (2015-05-13)
      Recognizing negative and speculative information is highly relevant for sentiment analysis. This paper presents a machine-learning approach to automatically detect this kind of information in the review domain. The resulting system works in two steps: in the first pass, negation/speculation cues are identified, and in the second phase the full scope of these cues is determined. The system is trained and evaluated on the Simon Fraser University Review corpus, which is extensively used in opinion mining. The results show how the proposed method outstrips the baseline by as much as roughly 20% in the negation cue detection and around 13% in the scope recognition, both in terms of F1. In speculation, the performance obtained in the cue prediction phase is close to that obtained by a human rater carrying out the same task. In the scope detection, the results are also promising and represent a substantial improvement on the baseline (up by roughly 10%). A detailed error analysis is also provided. The extrinsic evaluation shows that the correct identification of cues and scopes is vital for the task of sentiment analysis.
    • Incident detection using data from social media

      Salas, A; Georgakis, P; Petalas, Y (IEEE, 2018-03-14)
      © 2017 IEEE. Due to the rapid growth of population in the last 20 years, an increased number of instances of heavy recurrent traffic congestion has been observed in cities around the world. This rise in traffic has led to greater numbers of traffic incidents and subsequent growth of non-recurrent congestion. Existing incident detection techniques are limited to the use of sensors in the transportation network. In this paper, we analyze the potential of Twitter for supporting real-time incident detection in the United Kingdom (UK). We present a methodology for retrieving, processing, and classifying public tweets by combining Natural Language Processing (NLP) techniques with a Support Vector Machine algorithm (SVM) for text classification. Our approach can detect traffic related tweets with an accuracy of 88.27%.
    • A low computational approach for assistive esophageal adenocarcinoma and colorectal cancer detection

      Yu, Z; Yang, S; Zhou, K; Aggoun, A; Lotfi, Ahmad; Bouchachia, Hamid; Gegov, Alexander E; Langensiepen, Caroline S; McGinnity, T Martin (Springer International Publishing, 2018-08-11)
      © Springer Nature Switzerland AG 2019. In this paper, we aim to develop a low-computational system for real-time image processing and analysis in endoscopy images for the early detection of the human esophageal adenocarcinoma and colorectal cancer. Rich statistical features are used to train an improved machine-learning algorithm. Our algorithm can achieve a real-time classification of malign and benign cancer tumours with a significantly improved detection precision compared to the classical HOG method as a reference when it is implemented on real time embedded system NVIDIA TX2 platform. Our approach can help to avoid unnecessary biopsies for patients and reduce the over diagnosis of clinically insignificant cancers in the future.