Robust Mean Estimation on Highly Incomplete Data with Arbitrary Outliers
- URL: http://arxiv.org/abs/2008.08071v5
- Date: Mon, 3 May 2021 04:25:56 GMT
- Title: Robust Mean Estimation on Highly Incomplete Data with Arbitrary Outliers
- Authors: Lunjia Hu, Omer Reingold
- Abstract summary: We study the problem of robustly estimating the mean of a $d$-dimensional distribution given $N$ examples.
We show algorithms that estimate the mean of the distribution with information-theoretically optimal dimension-independent error guarantees in nearly-linear time.
- Score: 7.224832132296238
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We study the problem of robustly estimating the mean of a $d$-dimensional
distribution given $N$ examples, where most coordinates of every example may be
missing and $\varepsilon N$ examples may be arbitrarily corrupted. Assuming
each coordinate appears in a constant factor more than $\varepsilon N$
examples, we show algorithms that estimate the mean of the distribution with
information-theoretically optimal dimension-independent error guarantees in
nearly-linear time $\widetilde O(Nd)$. Our results extend recent work on
computationally-efficient robust estimation to a more widely applicable
incomplete-data setting.
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