The Benefits of Population Diversity in Evolutionary Algorithms: A Survey of Rigorous Runtime Analyses
This is an incremental survey that synthesizes existing rigorous analyses to clarify the role of diversity in evolutionary algorithms for researchers in optimization.
The paper surveys runtime analyses demonstrating that population diversity in evolutionary algorithms improves global exploration, crossover effectiveness, dynamic optimization, and Pareto front search.
Population diversity is crucial in evolutionary algorithms to enable global exploration and to avoid poor performance due to premature convergence. This book chapter reviews runtime analyses that have shown benefits of population diversity, either through explicit diversity mechanisms or through naturally emerging diversity. These works show that the benefits of diversity are manifold: diversity is important for global exploration and the ability to find several global optima. Diversity enhances crossover and enables crossover to be more effective than mutation. Diversity can be crucial in dynamic optimization, when the problem landscape changes over time. And, finally, it facilitates search for the whole Pareto front in evolutionary multiobjective optimization. The presented analyses rigorously quantify the performance of evolutionary algorithms in the light of population diversity, laying the foundation for a rigorous understanding of how search dynamics are affected by the presence or absence of population diversity and the introduction of diversity mechanisms.