Benchmarking on Tasks That Matter: Dataset Selection for Preserving Model Rankings

2026-06-26

AI Summary

This work addresses the high cost of machine learning benchmarking by proposing a systematic framework to efficiently select small, representative subsets of datasets while preserving model ranking stability. The study presents the first comprehensive evaluation of various dataset selection strategies—including clustering, A/D-optimal experimental designs, random baselines, and a greedy farthest-first (FAFI) approach—on rank fidelity. It derives a theoretical upper bound on Spearman rank correlation error for FAFI and integrates bootstrap aggregation to yield statistically rigorous confidence intervals for comparing strategy performance. Empirical results demonstrate that as few as five datasets suffice to achieve 0.95 rank correlation in time series classification, significantly outperforming random selection in NLP tasks, though gains are limited in recommendation systems.

Abstract

Benchmarks of machine learning models often include many datasets, making evaluation expensive. For efficiency, it is preferable to perform evaluations on small, representative datasets instead. The selection of such subsets typically relies on heuristics and is rarely analyzed for the robustness of the resulting model rankings. We introduce a framework to perform the task of selecting datasets subsets with an evaluation of how different selection strategies preserve the global model rankings. Our framework includes bootstrap aggregation, which provides valid confidence intervals, allowing a principled comparison of selection strategies. We consider clustering, design criteria (A/D-optimality), random baselines, and greedy farthest-first (FAFI). For the latter, we derive upper bounds on selection quality in terms of ranking errors as a function of the number of selected datasets. Empirically, in time series classification (TSC, 112 datasets) and in a supplementary natural language processing benchmark derived from MTEB (57 tasks), several selection strategies improve rank preservation compared with random subsets, including simple FAFI. In contrast, in recommender systems (30 datasets), the improvement of strategies over random selection is small and typically statistically insignificant. For TSC, our best-performing strategy achieves a Spearman correlation of 0.95 with the full benchmark model rankings using only five selected datasets. Additional experiments indicate that the effectiveness of selection approaches depends on both the quality of dataset representations and the scale of the benchmarking regime.

Problem

• dataset selection
• model ranking
• benchmarking
• rank preservation
• representative subset

Innovation

• dataset selection
• model ranking preservation
• bootstrap aggregation
• farthest-first traversal
• benchmark efficiency