In this work, we consider the sample complexity required for testing the monotonicity of distributions over partial orders. A distribution p over a poset is {\em monotone} if, for any pair of domain elements x and y such that x⪯y, p(x)≤p(y). To understand the sample complexity of this problem, we introduce a new property called \emph{bigness} over a finite domain, where the distribution is Tbig if the minimum probability for any domain element is at least T. We establish a lower bound of Ω(n/logn) for testing bigness of distributions on domains of size n. We then build on these lower bounds to give Ω(n/logn) lower bounds for testing monotonicity over a matching poset of size n and significantly improved lower bounds over the hypercube poset. We give sublinear sample complexity bounds for testing bigness and for testing monotonicity over the matching poset. We then give a number of tools for analyzing upper bounds on the sample complexity of the monotonicity testing problem.
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Towards Testing Monotonicity of Distributions Over General Posets
In this work, we consider the sample complexity required for testing the monotonicity of distributions over partial orders. A distribution p over a poset is monotone if, for any pair of domain elements x and y such that x ⪯ y, p(x) ≤ p(y).
To understand the sample complexity of this problem, we introduce a new property
called bigness over a finite domain, where the distribution is Tbig if the minimum probability for any domain element is at least T. We establish a lower bound of Ω(n/ log n) for testing bigness of distributions on domains of size n. We then build on these lower bounds to give Ω(n/ log n) lower bounds for testing monotonicity over a matching poset of size n and significantly improved lower bounds over the hypercube poset. We give sublinear sample complexity bounds for testing bigness and for testing monotonicity over the matching poset. We then give a number of tools for analyzing upper bounds on the sample complexity of the monotonicity testing problem. The previous lower bound for testing Monotonicity of
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 NSFPAR ID:
 10112888
 Date Published:
 Journal Name:
 Proceedings of the ThirtySecond Conference on Learning Theory (COLT 2019)
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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