Unleashing the Potential of Differential Evolution through Individual-Level Strategy Diversity

TL;DR

This paper introduces iStratDE, a simple yet effective variant of Differential Evolution that assigns fixed strategies at the individual level, enhancing performance and enabling efficient parallel computation without adaptation.

Contribution

The paper presents iStratDE, a novel DE variant with static individual-level strategy assignment, demonstrating improved performance and scalability over adaptive methods.

Findings

iStratDE matches or surpasses adaptive DE variants on benchmarks.

It enables efficient parallel execution suitable for GPU computing.

The convergence of iStratDE is theoretically established.

Abstract

Since Differential Evolution (DE) is sensitive to strategy choice, most existing variants pursue performance through adaptive mechanisms or intricate designs. While these approaches focus on adjusting strategies over time, the structural benefits that static strategy diversity may bring remain largely unexplored. To bridge this gap, we study the impact of individual-level strategy diversity on DE's search dynamics and performance, and introduce iStratDE (DE with individual-level strategies), a minimalist variant that assigns mutation and crossover strategies independently to each individual at initialization and keeps them fixed throughout the evolutionary process. By injecting diversity at the individual level without adaptation or feedback, iStratDE cultivates persistent behavioral heterogeneity that is especially effective with large populations. Moreover, its communication-free construction possesses intrinsic concurrency, thereby enabling efficient parallel execution and straightforward scaling for GPU computing. We further provide a convergence analysis of iStratDE under standard reachability assumptions, which establishes the almost-sure convergence of the best-so-far fitness. Extensive experiments on the CEC2022 benchmark suite and robotic control tasks demonstrate that iStratDE matches or surpasses established adaptive DE variants. These results highlight individual-level strategy assignment as a straightforward yet effective mechanism for enhancing DE's performance. The source code of iStratDE is publicly accessible at: https://github.com/EMI-Group/istratde.