Learning Adaptive Value of Information for Structured Prediction
David J. Weiss, Ben Taskar · 2013
Discriminative methods for learning structured models have enabled wide-spread use of very rich feature representations. However, the computational cost of fea-ture extraction is prohibitive for large-scale or time-sensitive applications, often dominating the cost of inference in the models. Significant efforts have been de-voted to sparsity-based model selection to decrease this cost. Such feature se-lection methods control computation statically and miss the opportunity to fine-tune feature extraction to each input at run-time. We address the key challenge of learning to control fine-grained feature extraction adaptively, exploiting non-homogeneity of the data. We propose an architecture that uses a rich feedback loop between extraction and prediction. The run-time control policy is learned us-ing efficient value-function approximation, which adaptively determines the value of information of features at the level of individual variables for each input. We demonstrate significant speedups over state-of-the-art methods on two challeng-ing datasets. For articulated pose estimation in video, we achieve a more accurate state-of-the-art model that is also faster, with similar results on an OCR task. 1