We study the following computational problem: for which values of k, the majority of n bits MAJn can be computed with a depth two formula whose each gate computes a majority function of at most k bits? The corresponding computational model is denoted by MAJk ∘ MAJk. We observe that the minimum value of k for which there exists a MAJk ∘ MAJk circuit that has high correlation with the majority of n bits is equal to Θ(n1/2). We then show that for a randomized MAJk ∘ MAJk circuit computing the majority of n input bits with high probability for every input, the minimum value of k is equal to n2/3 + o(1). We show a worst case lower bound: if a MAJk ∘ MAJk circuit computes the majority of n bits correctly on all inputs, then k ≥ n13/19 + o(1).

Original languageEnglish
Pages (from-to)956-986
JournalTheory of Computing Systems
Volume63
Issue number5
Early online date29 Nov 2018
DOIs
StatePublished - Jul 2019
Externally publishedYes

    Research areas

  • Average case, Circuit complexity, Constant depth, Correlation, Majority, Threshold, Worst case

    Scopus subject areas

  • Theoretical Computer Science
  • Computational Theory and Mathematics

ID: 49820484