Active Subspace
Active subspaces are low-dimensional representations of high-dimensional data that capture the most influential directions for a given function or model. Research focuses on identifying these subspaces efficiently, often employing techniques like gradient-based methods, principal component analysis extensions, and Riemannian geometry for specific data types (e.g., covariance matrices). This methodology improves efficiency in various applications, including deep learning training, uncertainty quantification in generative models, and robust subspace recovery in computer vision, by reducing computational complexity and enhancing interpretability. The impact spans diverse fields, from materials science and drug discovery to reinforcement learning and image processing.