Every Linear Threshold Function has a Low-Weight Approximator

  • Authors:
  • Rocco A. Servedio

  • Affiliations:
  • Columbia University, USA

  • Venue:
  • CCC '06 Proceedings of the 21st Annual IEEE Conference on Computational Complexity
  • Year:
  • 2006

Quantified Score

Hi-index 0.01

Visualization

Abstract

Given any linear threshold function f on n Boolean variables, we construct a linear threshold function g which disagrees with f on at most an \in fraction of inputs and has integer weights each of magnitude at most \sqrt n· 2 x O(1/ \in^2). We show that the construction is optimal in terms of its dependence on n by proving a lower bound of O(\sqrt n) on the weights required to approximate a particular linear threshold function.