Local Optima Correlation Assisted Adaptive Operator Selection

TL;DR

This paper introduces an empirical analysis of local optima correlations among search operators in combinatorial optimization, proposing a new adaptive operator selection method that improves search efficiency.

Contribution

It develops a novel correlation measure for operators and leverages it to enhance adaptive operator selection in metaheuristics.

Findings

Correlation patterns are consistent across problem instances.

The proposed method outperforms existing adaptive operator selection techniques.

Improved search efficiency by avoiding redundant exploration.

Abstract

For solving combinatorial optimisation problems with metaheuristics, different search operators are applied for sampling new solutions in the neighbourhood of a given solution. It is important to understand the relationship between operators for various purposes, e.g., adaptively deciding when to use which operator to find optimal solutions efficiently. However, it is difficult to theoretically analyse this relationship, especially in the complex solution space of combinatorial optimisation problems. In this paper, we propose to empirically analyse the relationship between operators in terms of the correlation between their local optima and develop a measure for quantifying their relationship. The comprehensive analyses on a wide range of capacitated vehicle routing problem benchmark instances show that there is a consistent pattern in the correlation between commonly used operators. Based on this newly proposed local optima correlation metric, we propose a novel approach for adaptively selecting among the operators during the search process. The core intention is to improve search efficiency by preventing wasting computational resources on exploring neighbourhoods where the local optima have already been reached. Experiments on randomly generated instances and commonly used benchmark datasets are conducted. Results show that the proposed approach outperforms commonly used adaptive operator selection methods.