Title: "Machine Learning Meets Signal Processing Algorithm Optimization" Subtitle: "Features? What are Features? Cooley-Tukey? Huh?" Abstract: This talk reports on our work and results framing signal processing algorithm optimization as a machine learning task. A single signal processing algorithm can be represented by many different but mathematically equivalent formulas. When these formulas are implemented in actual code, they have very different running times. Signal processing optimization is concerned with finding a formula that implements the algorithm as efficiently as possible. Unfortunately, a correct mapping between a mathematical formula and its running time is unknown. However empirical performance data can be gathered for a variety of formulas. This data offers an interesting opportunity to learn to predict running time performance. In this talk we present two major results along this direction: (1) Different sets of features are identified for mathematical formulas that distinguish them into partitions with significantly different running times, and (2) A function approximator can learn to accurately predict the running time of a formula given a limited set of training data. Showing the impact of selecting different features to describe the input, this work contributes an extensive study on the role of learning for this novel task.