Multi-Modal Distance Metric Learning

Multi-modal data is dramatically increasing with the fast growth of social media. Learning a good distance measure for data with multiple modalities is of vital importance for many applications, including retrieval, clustering, classification and recommendation. In this paper, we propose an effective and scalable multi-modal distance metric learning framework. Based on the multi-wing harmonium model, our method provides a principled way to embed data of arbitrary modalities into a single latent space, of which an optimal distance metric can be learned under proper supervision, i.e., by minimizing the distance between similar pairs whereas maximizing the distance between dissimilar pairs. The parameters are learned by jointly optimizing the data likelihood under the latent space model and the loss induced by distance supervision, thereby our method seeks a balance between explaining the data and providing an effective distance metric, which naturally avoids overfitting. We apply our general framework to text/image data and present empirical results on retrieval and classification to demonstrate the effectiveness and scalability.