{ "id": "2112.09181", "version": "v2", "published": "2021-12-16T20:10:56.000Z", "updated": "2023-03-16T12:57:21.000Z", "title": "Approximation of functions with one-bit neural networks", "authors": [ "C. Sinan Güntürk", "Weilin Li" ], "comment": "45 pages, 7 figures, significant changes and additions", "categories": [ "cs.LG", "cs.IT", "cs.NA", "math.IT", "math.NA" ], "abstract": "The celebrated universal approximation theorems for neural networks roughly state that any reasonable function can be arbitrarily well-approximated by a network whose parameters are appropriately chosen real numbers. This paper examines the approximation capabilities of one-bit neural networks -- those whose nonzero parameters are $\\pm a$ for some fixed $a\\not=0$. One of our main theorems shows that for any $f\\in C^s([0,1]^d)$ with $\\|f\\|_\\infty<1$ and error $\\varepsilon$, there is a $f_{NN}$ such that $|f(\\boldsymbol{x})-f_{NN}(\\boldsymbol{x})|\\leq \\varepsilon$ for all $\\boldsymbol{x}$ away from the boundary of $[0,1]^d$, and $f_{NN}$ is either implementable by a $\\{\\pm 1\\}$ quadratic network with $O(\\varepsilon^{-2d/s})$ parameters or a $\\{\\pm \\frac 1 2 \\}$ ReLU network with $O(\\varepsilon^{-2d/s}\\log (1/\\varepsilon))$ parameters, as $\\varepsilon\\to0$. We establish new approximation results for iterated multivariate Bernstein operators, error estimates for noise-shaping quantization on the Bernstein basis, and novel implementation of the Bernstein polynomials by one-bit quadratic and ReLU neural networks.", "revisions": [ { "version": "v2", "updated": "2023-03-16T12:57:21.000Z" } ], "analyses": { "keywords": [ "one-bit neural networks", "parameters", "iterated multivariate bernstein operators", "relu neural networks", "appropriately chosen real numbers" ], "note": { "typesetting": "TeX", "pages": 45, "language": "en", "license": "arXiv", "status": "editable" } } }