Bayesian Optimization is Superior to Random Search for Machine Learning Hyperparameter Tuning: Analysis of the Black-Box Optimization Challenge 2020
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Abstract (arXiv)
This paper presents the results and insights from the black-box optimization (BBO) challenge at NeurIPS 2020 which ran from July-October, 2020. The challenge emphasized the importance of evaluating derivative-free optimizers for tuning the hyperparameters of machine learning models. This was the first black-box optimization challenge with a machine learning emphasis. It was based on tuning (validation set) performance of standard machine learning models on real datasets. This competition has widespread impact as black-box optimization (e.g., Bayesian optimization) is relevant for hyperparameter tuning in almost every machine learning project as well as many applications outside of machine learning. The final leaderboard was determined using the optimization performance on held-out (hidden) objective functions, where the optimizers ran without human intervention. Baselines were set using the default settings of several open-source black-box optimization packages as well as random search.
Key facts. Cited by 146 papers in the map (data through 7 Oct 2026). Builds on 24 of its 67 references that are in the map. First posted on arXiv 20 Apr 2021.
Builds on
24 of 67 references.
References · 24
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Citing papers per year: 2021: 19; 2022: 36; 2023: 30; 2024: 26; 2025: 22; 2026: 13.
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