## Abstract

Networks in many real-world applications come with an inherent uncertainty in their structure, due to e.g., noisy measurements, inference and prediction models, or for privacy purposes. Modeling and analyzing uncertain graphs has attracted a great deal of attention. Among the various graph analytic tasks studied, the extraction of dense substructures, such as cores or trusses, has a central role. In this paper, we study the problem of (k, 3)-truss indexing and querying over an uncertain graph . A (k, 3)-truss is the largest subgraph of , such that the probability of each edge being contained in at least k - 2 triangles is no less than 3. Our first proposal, CPT-index, keeps all the (k, 3)-trusses: retrieval for any given k and ?can be executed in an optimal linear time w.r.t. the graph size of the queried (k, 3)-truss. We develop a bottom-up CPT-indexconstruction scheme and an improved algorithm for fast CPT-indexconstruction using top-down graph partitions. For trading off between (k, 3)-truss offline indexing and online querying, we further develop an approximate indexing approach ( Âµ, "r)-APXequipped with two parameters, Âµ and "r, that govern tolerated errors. Extensive experiments using large-scale uncertain graphs with 261 million edges validate the efficiency of our proposed indexing and querying algorithms against state-of-the-art methods.

Original language | English |
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Title of host publication | WWW '21: Proceedings of the Web Conference 2021 |

Editors | Jure Leskovec, Marko Grobelnik |

Publisher | Association for Computing Machinery (ACM) |

Pages | 354-366 |

Number of pages | 13 |

ISBN (Electronic) | 9781450383127 |

DOIs | |

Publication status | Published - 19 Apr 2021 |

Event | 2021 World Wide Web Conference, WWW 2021 - Ljubljana, Slovenia Duration: 19 Apr 2021 → 23 Apr 2021 |

### Conference

Conference | 2021 World Wide Web Conference, WWW 2021 |
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Country/Territory | Slovenia |

City | Ljubljana |

Period | 19/04/21 → 23/04/21 |

## Scopus Subject Areas

- Computer Networks and Communications
- Software

## User-Defined Keywords

- Indexing
- Probabilistic k-truss
- Query
- Uncertain graph