Multi-resolution Spatial Event Forecasting in Social Media
Liang Zhao, Feng Chen, Chang‐Tien Lu, Naren Ramakrishnan · 2016
Social media has become a significant surrogate forspatial event forecasting. The accuracy and discernibility of aspatial event forecasting model are two key concerns, whichrespectively determine how accurate and how detailed themodel's predictions could be. Existing work pays most attentionon the accuracy alone, seldom considering the accuracyand discernibility simultaneously, because this would requiresa considerably more sophisticated model while still sufferingfrom several challenges: 1) the precise formulation of thetrade-off between accuracy and discernibility, 2) the scarcityof social media data with a high spatial resolution, and 3)the characterization of spatial correlation and heterogeneity. This paper proposes a novel feature learning model thatconcurrently addresses all the above challenges by formulatingprediction tasks for different locations with different spatialresolutions, allowing the heterogeneous relationships amongthe tasks to be characterized. This characterization is thenintegrated into our new model based on multitask learning, whose parameters are optimized by our proposed algorithmbased on the Alternative Direction Method of Multipliers(ADMM). Extensive experimental evaluations on 11 datasetsfrom different domains demonstrated the effectiveness of ourproposed approach.