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Feature Engineering for Activity Recognition
PhD Thesis Proposal Defence Title: "Feature Engineering for Activity Recognition" by Mr. Yin ZHU Abstract: In today's world, we have increasingly sophisticated means of recording the daily activity of humans as well as other moving objects in both physical and virtual worlds. These recorded activities include phone calls, uses of Apps on smartphones, and expression of opinions over social-network objects such as photos. These activities and actions give rise to a huge amount of data. Activity recognition aims to understand users’ actions and intentions based on models built from these data. Having accurate activity recognition allows us to recognition the semantic functions of places, to help users and managers identify spammers in an online social network, and to predict the future activity levels of social-network users. In this PhD research, we view activity recognition as a form of classification. Good discriminative features are essential in building a high-performance classifier. Traditionally, feature engineering is performed by humans through manual labor. In this thesis, we propose a novel method to automatically or semi-automatically extract a large number of features from very high volumes of data. I first propose a semi-automatic feature engineering method that explores the relationship between activity signals and context. By uncovering the relationship between actions and their context, we can automatically construct new features. We apply this feature engineering method to two different applications, semantic place prediction and social activity level prediction. We call this method conditional-feature method. We then propose a second feature engineering method based on social information, by proposing a novel socially regularized feature learning. This method complements the above-mentioned conditional-feature method. We apply this socially regularized method to two applications: spammer detection in a social network and social activity level recognition. We experimentally verify the above feature-engineering methods and show that they are superior to existing features for activity recognition. Date: Tuesday, 1 April 2014 Time: 2:00pm - 4:00pm Venue: Room 5507 lifts 25/26 Committee Members: Prof. Qiang Yang (Supervisor) Dr. Ke Yi (Chairperson) Dr. Lei Chen Dr. Huamin Qu **** ALL are Welcome ****