S-CARD-CMSA: A Score-Aware Candidate Archive with Density-Filtered Reporting for Multimodal Optimization

Dikshit Chauhan

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arXiv · 2607.13764

S-CARD-CMSA: A Score-Aware Candidate Archive with Density-Filtered Reporting for Multimodal Optimization

Dikshit Chauhan

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Abstract

Multimodal optimization aims to locate multiple globally optimal or near-optimal solutions in a single run. This paper presents \emph{S-CARD-CMSA}, a score-aware candidate-archive and density-filtered reporting framework built on the covariance matrix self-adaptation evolution strategy with repelling subpopulations (RS-CMSA-ESII). The method is developed for the IEEE CEC 2026 Competition on Benchmarking Niching Methods for Multimodal Optimization. Rather than modifying the core search dynamics of RS-CMSA-ESII, S-CARD-CMSA preserves its sampling, covariance adaptation, taboo-region update, restart, and termination mechanisms. Two conservative extensions are introduced. First, a passive secondary candidate archive records the restart-level best candidates without influencing the search trajectory. Second, a score-aware density-filtered reporting rule constructs the final solution set by balancing robust peak ratio and precision-driven F1-score. Development experiments show that the density-filtered rule preserves the peak coverage obtained by a medium score-aware rule while reducing redundant reports. On a broader validation subset, it maintains the same mean RPR while improving mean precision, F1-score, and the official-score-oriented average. The method does not use true global-minimum locations during optimization; such information is used only for offline development analysis and post-run scoring. The source code of S-CARD-CMSA is available at https://github.com/ChauhanDikshit.

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Dikshit Chauhan. 2026-07-15. S-CARD-CMSA: A Score-Aware Candidate Archive with Density-Filtered Reporting for Multimodal Optimization. https://arxiv.org/abs/2607.13764

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