### Abstract

Original language | English |
---|---|

Pages (from-to) | 96-103 |

Number of pages | 8 |

Journal | Pattern Recognition Letters |

Volume | 87 |

Early online date | 9 Sep 2016 |

DOIs | |

Publication status | Published - 1 Feb 2017 |

### Cite this

*Pattern Recognition Letters*,

*87*, 96-103. https://doi.org/10.1016/j.patrec.2016.08.019

}

*Pattern Recognition Letters*, vol. 87, pp. 96-103. https://doi.org/10.1016/j.patrec.2016.08.019

**Quantum kernels for unattributed graphs using discrete-time quantum walks.** / Bai, Lu; Rossi, Luca; Cui, Lixin; Zhang, Zhihong; Ren, Peng; Bai, Xiao; Hancock, Edwin R.

Research output: Contribution to journal › Article

TY - JOUR

T1 - Quantum kernels for unattributed graphs using discrete-time quantum walks

AU - Bai, Lu

AU - Rossi, Luca

AU - Cui, Lixin

AU - Zhang, Zhihong

AU - Ren, Peng

AU - Bai, Xiao

AU - Hancock, Edwin R.

PY - 2017/2/1

Y1 - 2017/2/1

N2 - In this paper, we develop a new family of graph kernels where the graph structure is probed by means of a discrete-time quantum walk. Given a pair of graphs, we let a quantum walk evolve on each graph and compute a density matrix with each walk. With the density matrices for the pair of graphs to hand, the kernel between the graphs is defined as the negative exponential of the quantum Jensen–Shannon divergence between their density matrices. In order to cope with large graph structures, we propose to construct a sparser version of the original graphs using the simplification method introduced in Qiu and Hancock (2007). To this end, we compute the minimum spanning tree over the commute time matrix of a graph. This spanning tree representation minimizes the number of edges of the original graph while preserving most of its structural information. The kernel between two graphs is then computed on their respective minimum spanning trees. We evaluate the performance of the proposed kernels on several standard graph datasets and we demonstrate their effectiveness and efficiency.

AB - In this paper, we develop a new family of graph kernels where the graph structure is probed by means of a discrete-time quantum walk. Given a pair of graphs, we let a quantum walk evolve on each graph and compute a density matrix with each walk. With the density matrices for the pair of graphs to hand, the kernel between the graphs is defined as the negative exponential of the quantum Jensen–Shannon divergence between their density matrices. In order to cope with large graph structures, we propose to construct a sparser version of the original graphs using the simplification method introduced in Qiu and Hancock (2007). To this end, we compute the minimum spanning tree over the commute time matrix of a graph. This spanning tree representation minimizes the number of edges of the original graph while preserving most of its structural information. The kernel between two graphs is then computed on their respective minimum spanning trees. We evaluate the performance of the proposed kernels on several standard graph datasets and we demonstrate their effectiveness and efficiency.

U2 - 10.1016/j.patrec.2016.08.019

DO - 10.1016/j.patrec.2016.08.019

M3 - Article

VL - 87

SP - 96

EP - 103

JO - Pattern Recognition Letters

JF - Pattern Recognition Letters

SN - 0167-8655

ER -