Explicit ensemble attention learning for improving visual question answering

Visual Question Answering (VQA) is among the most difficult multi-modal problems as it requires a machine to be able to properly understand a question about a reference image and then infer the correct answer. Providing reliable attention information is crucial for correctly answering the questions. However, existing methods usually only use implicitly trained attention models that are frequently unable to attend to the correct image regions. To this end, an explicitly trained attention model for VQA is proposed in this paper. The proposed method utilizes attention-oriented word embeddings that allows efficiently learning the common representation spaces. Furthermore, multiple attention models of varying complexity are employed as a way of realizing a mixture of experts attention model, further improving the VQA accuracy over a single attention model. The effectiveness of the proposed method is demonstrated using extensive experiments on the Visual7W dataset that provides visual attention ground truth information. (C) 2018 Elsevier B.V. All rights reserved.