Abstract
A signed majority function is a linear threshold function f:{+1,−1}n→{+1,−1} of the form \(f(x)=\operatorname{sign}(\sum_{i=1}^{n} \sigma _{i} x_{i})\) where each σ i ∈{+1,−1}. Signed majority functions are a highly symmetrical subclass of the class of all linear threshold functions, which are functions of the form \(\operatorname{sign} (\sum_{i=1}^{n} w_{i} x_{i} - \theta)\) for arbitrary real w i ,θ.
We study the query complexity of testing whether an unknown f:{+1,−1}n→{+1,−1} is a signed majority function versus ϵ-far from every signed majority function. While it is known (SIAM J. Comput. 39(5):2004–2047, 2010) that the broader class of all linear threshold functions is testable with poly(1/ϵ) queries (independent of n), prior to our work the best upper bound for signed majority functions was \(O(\sqrt{n}) \cdot \mathrm{poly} (1/\epsilon)\) queries (via a non-adaptive algorithm), and the best lower bound was Ω(logn) queries for non-adaptive algorithms (Proceedings of the 13th International Workshop on Approximation, Randomization and Combinatorial Optimization (RANDOM), pp. 646–657, 2009).
As our main results we exponentially improve both these prior bounds for testing signed majority functions:
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(Upper bound) We give a poly(logn,1/ϵ)-query adaptive algorithm (which is computationally efficient) for this testing problem;
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(Lower bound) We show that any non-adaptive algorithm for testing the class of signed majorities to constant accuracy must make n Ω(1) queries. This directly implies a lower bound of Ω(logn) queries for any adaptive algorithm.
Our testing algorithm performs a sequence of restrictions together with consistency checks to ensure that each successive restriction is “compatible” with the function prior to restriction. This approach is used to transform the original n-variable testing problem into a testing problem over poly(logn,1/ϵ) variables where a simple direct method can be applied. Analysis of the degree-1 Fourier coefficients plays an important role in our proofs.
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Notes
In particular, in all that follows we make statements that hold with high probability, without explicitly stating this.
This can be done either by running the \(O(\sqrt{n}\cdot\mathrm{poly}(1/\epsilon))\)-queries algorithm of [27] (which runs in poly(n,1/ϵ) time), or by simply running a proper learning algorithm with time and query complexity poly(n,1/ϵ) for the class SMAJ and applying the well-known result that the query complexity of testing a class of functions is essentially upper bounded by the query complexity of proper learning the class [19, Prop. 3.1.1]. To properly learn a function f∈SMAJ, i.e., f=Maj σ for σ∈{+1,−1}n, it suffices to find σ i for each i∈[n] and this can easily be done by performing poly(n) queries.
References
Ailon, N., Chazelle, B.: Information theory in property testing and monotonicity testing in higher dimension. Inf. Comput. 204(11), 1704–1717 (2006)
Alon, N., Kaufman, T., Krivelevich, M., Litsyn, S., Ron, D.: Testing Reed-Muller codes. IEEE Trans. Inf. Theory 51(11), 4032–4039 (2005)
Blais, E.: Improved bounds for testing juntas. In: Proceedings of the 12th International Workshop on Approximation, Randomization and Combinatorial Optimization (RANDOM), pp. 317–330 (2008)
Blais, E.: Testing juntas nearly optimally. In: Proceedings of the 41st Annual ACM Symposium on Theory of Computing (STOC), pp. 151–158 (2009)
Blais, E., O’Donnell, R.: Lower bounds for testing function isomorphism. In: Proceedings of the 25th Annual IEEE Conference on Computational Complexity (CCC), pp. 235–246 (2010)
Blum, M., Luby, M., Rubinfeld, R.: Self-testing/correcting with applications to numerical problems. J. Comput. Syst. Sci. 47(3), 549–595 (1993)
Briët, J., Chakraborty, S., García-Soriano, D., Matsliah, A.: Monotonicity testing and shortest-path routing on the cube. Combinatorica 32(1), 35–53 (2012)
Brody, J., Matulef, K., Wu, C.: Lower bounds for testing computability by small width OBDDs. In: Proceedings of the 8th Annual Conference on Theory and Applications of Models of Computation (TAMC), pp. 320–331 (2011)
de Wolf, R.: A brief introduction to Fourier analysis on the boolean cube. Theory Comput. 1, 1–20 (2008)
Diakonikolas, I., Lee, H., Matulef, K., Onak, K., Rubinfeld, R., Servedio, R., Wan, A.: Testing for concise representations. In: Proceedings of the 48th Annual Symposium on Computer Science (FOCS), pp. 549–558 (2007)
Dodis, Y., Goldreich, O., Lehman, E., Raskhodnikova, S., Ron, D., Samorodnitsky, A.: Improved testing algorithms for monotonicity. In: Proceedings of the Third International Workshop on Randomization and Approximation Techniques in Computer Science (RANDOM), pp. 97–108 (1999)
Dubhashi, D., Panconesi, A.: Concentration of Measure for the Analysis of Randomized Algorithms. Cambridge University Press, Cambridge (2009)
Fischer, E.: The art of uninformed decisions: a primer to property testing. Bull. Eur. Assoc. Theor. Comput. Sci. 75, 97–126 (2001)
Fischer, E., Kindler, G., Ron, D., Safra, S., Samorodnitsky, A.: Testing juntas. J. Comput. Syst. Sci. 68(4), 753–787 (2004)
Fischer, E., Lehman, E., Newman, I., Raskhodnikova, S., Rubinfeld, R., Samorodnitsky, A.: Monotonicity testing over general poset domains. In: Proceedings of the 34th Annual ACM Symposium on Theory of Computing (STOC), pp. 474–483 (2002)
Goldreich, O.: On testing computability by small width OBDDs. In: Proceedings of the 14th International Workshop on Approximation, Randomization and Combinatorial Optimization (RANDOM), pp. 574–587 (2010)
Goldreich, O. (ed.): Property Testing: Current Research and Surveys. LNCS, vol. 6390. Springer, Berlin (2010)
Goldreich, O., Goldwasser, S., Lehman, E., Ron, D., Samordinsky, A.: Testing monotonicity. Combinatorica 20(3), 301–337 (2000)
Goldreich, O., Goldwasser, S., Ron, D.: Property testing and its connection to learning and approximation. J. ACM 45(4), 653–750 (1998)
Gopalan, P., O’Donnell, R., Servedio, R., Shpilka, A., Wimmer, K.: Testing Fourier dimensionality and sparsity. SIAM J. Comput. 40(4), 1075–1100 (2011)
Gopalan, P., O’Donnell, R., Wu, Y., Zuckerman, D.: Fooling functions of halfspaces under product distributions. In: Proceedings of the 25th Annual IEEE Conference on Computational Complexity (CCC), pp. 223–234 (2010)
Halevy, S., Kushilevitz, E.: Testing monotonicity over graph products. Random Struct. Algorithms 33(1), 44–67 (2008)
Jutla, C.S., Patthak, A.C., Rudra, A., Zuckerman, D.: Testing low-degree polynomials over prime fields. Random Struct. Algorithms 35(2), 163–193 (2009)
Kaufman, T., Ron, D.: Testing polynomials over general fields. SIAM J. Comput. 35(3), 779–802 (2006)
König, H., Schütt, C., Tomczak-Jaegermann, N.: Projection constants of symmetric spaces and variants of Khintchine’s inequality. J. Reine Angew. Math. 511, 1–42 (1999)
Matulef, K., O’Donnell, R., Rubinfeld, R., Servedio, R.: Testing halfspaces. SIAM J. Comput. 39(5), 2004–2047 (2010)
Matulef, K., O’Donnell, R., Rubinfeld, R., Servedio, R.A.: Testing ±1-weight halfspaces. In: Proceedings of the 13th International Workshop on Approximation, Randomization and Combinatorial Optimization (RANDOM), pp. 646–657 (2009)
Mossel, E.: Gaussian bounds for noise correlation of functions and tight analysis of long codes. In: Proceedings of the 49th IEEE Symposium on Foundations of Computer Science (FOCS), pp. 156–165 (2008)
O’Donnell, R.: Some topics in analysis of Boolean functions. In: Proceedings of the 40th Annual ACM Symposium on Theory of Computing (STOC), pp. 569–578 (2008)
Parnas, M., Ron, D., Samorodnitsky, A.: Testing basic Boolean formulae. SIAM J. Discrete Math. 16(1), 20–46 (2002)
Ron, D.: Property testing: a learning theory perspective. Found. Trends Mach. Learn. 1(3), 307–402 (2008)
Ron, D.: Algorithmic and analysis techniques in property testing. Found. Trends Theor. Comput. Sci. 5(2), 73–205 (2010)
Ron, D., Tsur, G.: Testing computability by width-two OBDDs. Theor. Comput. Sci. 420, 64–79 (2012)
Shiganov, I.S.: Refinement of the upper bound of a constant in the remainder term of the central limit theorem. J. Sov. Math. 35(3), 109–115 (1986)
Wikipedia contributors. Central binomial coefficient. Wikipedia, The Free Encyclopedia, accessed June 8 (2012). http://en.wikipedia.org/wiki/Central_binomial_coefficient
Yao, A.: Probabilistic computations: towards a unified measure of complexity. In: Proceedings of the Seventeenth Annual Symposium on Foundations of Computer Science (STOC), pp. 222–227 (1977)
Acknowledgements
We would like to thank Ryan O’Donnell and Gilad Tsur for discussions in the initial stages of this work.
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D. Ron was supported by ISF grants number 246/08 and 671/13.
R.A. Servedio was supported by NSF grants CCF-0915929 and CCF-1115703.
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Ron, D., Servedio, R.A. Exponentially Improved Algorithms and Lower Bounds for Testing Signed Majorities. Algorithmica 72, 400–429 (2015). https://doi.org/10.1007/s00453-013-9858-0
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DOI: https://doi.org/10.1007/s00453-013-9858-0