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arXiv · 2002.11541

On Learning a Hidden Directed Graph with Path Queries

Mano Vikash Janardhanan·Lev Reyzin
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Abstract

In this paper, we consider the problem of reconstructing a directed graph using path queries. In this query model of learning, a graph is hidden from the learner, and the learner can access information about it with path queries. For a source and destination node, a path query returns whether there is a directed path from the source to the destination node in the hidden graph. In this paper we first give bounds for learning graphs on $n$ vertices and $k$ strongly connected components. We then study the case of bounded degree directed trees and give new algorithms for learning "almost-trees" -- directed trees to which extra edges have been added. We also give some lower bound constructions justifying our approach.

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BibTeXRIS

Mano Vikash Janardhanan, Lev Reyzin. 2021-03-16. On Learning a Hidden Directed Graph with Path Queries. https://arxiv.org/abs/2002.11541

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