Unsupervised Learning of the Set of Local Maxima
- URL: http://arxiv.org/abs/2001.05026v1
- Date: Tue, 14 Jan 2020 19:56:36 GMT
- Title: Unsupervised Learning of the Set of Local Maxima
- Authors: Lior Wolf, Sagie Benaim, Tomer Galanti
- Abstract summary: Two functions are learned: (i) a set indicator c, which is a binary classifier, and (ii) a comparator function h that given two nearby samples, predicts which sample has the higher value of the unknown function v.
Loss terms are used to ensure that all training samples x are a local maxima of v, according to h and satisfy c(x)=1.
We present an algorithm, show an example where it is more efficient to use local maxima as an indicator function than to employ conventional classification, and derive a suitable generalization bound.
- Score: 105.60049730557706
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: This paper describes a new form of unsupervised learning, whose input is a
set of unlabeled points that are assumed to be local maxima of an unknown value
function v in an unknown subset of the vector space. Two functions are learned:
(i) a set indicator c, which is a binary classifier, and (ii) a comparator
function h that given two nearby samples, predicts which sample has the higher
value of the unknown function v. Loss terms are used to ensure that all
training samples x are a local maxima of v, according to h and satisfy c(x)=1.
Therefore, c and h provide training signals to each other: a point x' in the
vicinity of x satisfies c(x)=-1 or is deemed by h to be lower in value than x.
We present an algorithm, show an example where it is more efficient to use
local maxima as an indicator function than to employ conventional
classification, and derive a suitable generalization bound. Our experiments
show that the method is able to outperform one-class classification algorithms
in the task of anomaly detection and also provide an additional signal that is
extracted in a completely unsupervised way.
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