{ "id": "2402.07070", "version": "v2", "published": "2024-02-11T00:02:36.000Z", "updated": "2024-06-09T17:09:17.000Z", "title": "Efficient Algorithms for Sum-of-Minimum Optimization", "authors": [ "Lisang Ding", "Ziang Chen", "Xinshang Wang", "Wotao Yin" ], "categories": [ "math.OC" ], "abstract": "In this work, we propose a novel optimization model termed \"sum-of-minimum\" optimization. This model seeks to minimize the sum or average of $N$ objective functions over $k$ parameters, where each objective takes the minimum value of a predefined sub-function with respect to the $k$ parameters. This universal framework encompasses numerous clustering applications in machine learning and related fields. We develop efficient algorithms for solving sum-of-minimum optimization problems, inspired by a randomized initialization algorithm for the classic $k$-means (Arthur & Vassilvitskii, 2007) and Lloyd's algorithm (Lloyd, 1982). We establish a new tight bound for the generalized initialization algorithm and prove a gradient-descent-like convergence rate for generalized Lloyd's algorithm. The efficiency of our algorithms is numerically examined on multiple tasks, including generalized principal component analysis, mixed linear regression, and small-scale neural network training. Our approach compares favorably to previous ones based on simpler-but-less-precise optimization reformulations.", "revisions": [ { "version": "v2", "updated": "2024-06-09T17:09:17.000Z" } ], "analyses": { "keywords": [ "efficient algorithms", "lloyds algorithm", "initialization algorithm", "framework encompasses numerous clustering applications", "generalized principal component analysis" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }