tinyBenchmarks: evaluating LLMs with fewer examples

TL;DR

Proposes tinyBenchmarks using 100 examples with IRT and clustering to estimate LLM performance on benchmarks within 2% error.

cs.CL 🔴 Advanced 2024-02-23 44 views
Felipe Maia Polo Lucas Weber Leshem Choshen Yuekai Sun Gongjun Xu Mikhail Yurochkin
Large Language Models Efficient Benchmarking Bayesian Methods IRT Performance Estimation

Key Findings

Methodology

This work integrates Item Response Theory (IRT) with clustering and Bayesian inference to develop a sample-efficient performance estimation framework. It learns latent example parameters—difficulty and ability requirements—and employs anchor points to select representative samples. The Bayesian approach combines these with limited model responses to estimate full benchmark performance, achieving less than 2% error with only 100 curated examples. Extensive experiments on Open LLM Leaderboard, MMLU, HELM, and AlpacaEval demonstrate high correlation and ranking consistency, surpassing traditional sampling methods.

Key Results

  • On MMLU (14K questions), the IRT-based estimator with 100 examples achieved an average error below 1.9%, outperforming random sampling (>5%) and stratified sampling (~3%).
  • In HELM and AlpacaEval, tiny versions with 100 examples per scenario reliably reproduced full benchmark rankings with correlation coefficients above 0.95.
  • The hybrid gp-IRT estimator further improved stability, especially under model bias and distribution shifts, reducing variance and bias trade-offs.

Significance

This approach addresses the high cost and environmental impact of large-scale LLM evaluation, enabling rapid, low-cost performance monitoring. It facilitates iterative model development, hyperparameter tuning, and deployment decisions, fostering sustainable AI progress. By drastically reducing sample requirements, it democratizes access to benchmarking, especially for resource-constrained labs and industry players.

Technical Contribution

The paper introduces a novel combination of IRT modeling, anchor point clustering, and Bayesian inference for performance estimation. It develops a convex combination (gp-IRT) to balance bias and variance, with theoretical guarantees of consistency as sample size grows. The tools support multi-task, multi-scenario evaluation, representing a significant step beyond existing random or heuristic sampling methods, with formal error bounds and practical implementation.

Novelty

This is the first application of IRT in large-scale LLM performance estimation, integrating statistical psychometrics with modern NLP benchmarking. The combined use of anchor points, Bayesian modeling, and hybrid estimators offers unprecedented sample efficiency and accuracy, setting a new standard for low-cost benchmarking.

Limitations

  • IRT assumptions may break down in scenarios with extreme model biases or highly complex tasks, limiting estimation accuracy.
  • High-dimensional ability spaces and diverse task types pose challenges for stable parameter estimation.
  • Dependence on existing performance data restricts generalization to unseen models or novel tasks, requiring further validation.

Future Work

Future directions include adaptive sampling strategies, active learning integration, and extending models to multi-modal tasks. Improving robustness under distribution shifts and exploring deep learning-based ability modeling are also promising avenues.

AI Executive Summary

The rapid development of large language models (LLMs) has revolutionized NLP, but evaluating their performance remains costly and environmentally taxing. Traditional benchmarks like MMLU, HELM, and AlpacaEval contain tens of thousands of examples, making frequent assessments impractical. To address this, the authors introduce tinyBenchmarks, a novel framework that leverages statistical modeling—specifically Item Response Theory (IRT)—and clustering techniques to estimate model performance with only 100 curated examples per scenario.

The core idea is to learn latent parameters representing example difficulty and model ability, then select representative samples—anchor points—via clustering. Using Bayesian inference, the framework combines limited model responses with learned parameters to predict full benchmark performance, maintaining an error margin below 2%. Extensive experiments across multiple benchmarks demonstrate that this approach reliably reproduces full evaluation rankings, significantly reducing computational costs.

This methodology offers a transformative tool for AI research and industry, enabling rapid, cost-effective model monitoring, hyperparameter tuning, and deployment decisions. It also opens avenues for democratizing benchmarking, making high-quality evaluation accessible to resource-limited settings. The hybrid estimator (gp-IRT) further enhances robustness under distribution shifts and model biases. Future work will explore adaptive sampling, multi-modal capabilities, and deeper ability modeling, aiming to refine and extend this promising evaluation paradigm.

Deep Analysis

Background

随着GPT、BERT等模型的崛起,LLMs在多任务、多场景中的应用不断扩大。传统评估方法依赖庞大的示例集,导致成本高昂,难以快速迭代。已有工作如MMLU、HELM、AlpacaEval提供了丰富的基准,但规模庞大,评估耗时长。近年来,统计学中的IRT模型逐渐被引入AI评估,显示出潜力。本文结合IRT与贝叶斯推断,创新性地提出低样本、高精度的性能估算方法,旨在解决大规模模型评估的效率瓶颈。

Core Problem

当前大规模LLMs的性能评估面临样本量巨大、成本高昂的问题。传统方法需要数万示例,限制了模型快速迭代和调优。如何在保证准确性的同时,显著减少样本需求,成为行业难题。现有抽样策略在代表性和误差控制方面不足,难以满足实际需求。引入统计模型如IRT,结合智能样本选择,成为潜在解决方案。

Innovation

本文的创新点包括:1)将IRT模型引入大规模性能估算,学习示例的潜在难度和能力需求;2)利用anchor点聚类,优化样本代表性;3)结合贝叶斯推断,提升估算稳定性;4)提出混合估计(gp-IRT),融合随机抽样与模型推断优势。这些创新实现了低成本、高效率的性能评估体系,显著优于现有方法。

Methodology

  • �� 构建IRT模型,学习示例的潜在难度参数和能力需求。
  • �� 利用已有模型性能数据,进行anchor点聚类,提取代表性示例。
  • �� 采用贝叶斯推断,将少量模型响应与IRT参数结合,估算完整性能。
  • �� 设计混合估计(gp-IRT),调节参数λ,平衡两者优势。
  • �� 通过交叉验证确定IRT模型维度,确保模型表达能力。
  • �� 在多个基准上验证方法效果,比较不同采样策略的误差。

Experiments

使用公开模型性能数据,评估Open LLM Leaderboard、MMLU、HELM、AlpacaEval的样本效率。每个基准中,训练集占75%,测试集占25%。采样100示例,比较IRT、随机和分层采样的误差。指标包括平均误差(<2%优)、排名相关性(>0.95)等。验证模型偏差和任务复杂度的敏感性,确保方法鲁棒。

Results

在MMLU上,IRT策略用100示例实现了平均误差低于1.9%,优于随机采样的5%以上。在HELM和AlpacaEval中,tiny版本排名相关性超过0.95。混合估计(gp-IRT)提升了估算稳定性,尤其在模型偏差大时表现优越。多场景验证显示,该方法适应不同任务和偏差条件,显著降低评估成本。

Applications

适用于研究机构和企业快速监控模型性能,减少评估时间和成本。可用于模型调优、版本迭代,特别在资源有限或需频繁评估的场景。未来结合主动学习,动态调整样本采样策略,进一步提升效率。

Limitations & Outlook

模型偏差和任务复杂性可能影响IRT估算的准确性,尤其在极端场景。高维能力空间和多样任务带来参数估计难题。依赖已有性能数据,泛化到新模型或未知任务时存在偏差。未来需结合深度学习能力建模和自适应采样,增强鲁棒性。

Plain Language Accessible to non-experts

想象你在一家工厂里,要检查每个工人的工作水平。传统方式是让每个工人都做所有任务,既费时又费力。现在,你只挑几项代表性的任务(难度不同的),用这些任务来判断工人的整体水平。通过统计学的方法,你可以根据少量任务的表现,推算出他们在全部任务中的表现。这就像用少量试题,准确判断学生能力一样。这样既省时间,又能得到可靠的结果,非常适合需要频繁检测工人水平的工厂。

ELI14 Explained like you're 14

想象你在学校里,要知道每个学生的学习水平。以前,你可能让他们做很多题,花费很多时间。现在,你只挑几道不同难度的题,看看他们答对了多少,然后用数学方法推算出他们的整体水平。这就像用少量的试题,准确判断一个学生的能力一样。这样既快又准,还能节省老师的时间。这个方法用在AI模型上也是一样的,只用少量测试,就能知道它在所有任务中的表现,节省了很多计算资源和时间。

Abstract

The versatility of large language models (LLMs) led to the creation of diverse benchmarks that thoroughly test a variety of language models' abilities. These benchmarks consist of tens of thousands of examples making evaluation of LLMs very expensive. In this paper, we investigate strategies to reduce the number of evaluations needed to assess the performance of an LLM on several key benchmarks. For example, we show that to accurately estimate the performance of an LLM on MMLU, a popular multiple-choice QA benchmark consisting of 14K examples, it is sufficient to evaluate this LLM on 100 curated examples. We release evaluation tools and tiny versions of popular benchmarks: Open LLM Leaderboard, MMLU, HELM, and AlpacaEval 2.0. Our empirical analysis demonstrates that these tools and tiny benchmarks are sufficient to reliably and efficiently reproduce the original evaluation results.

cs.CL cs.AI cs.LG stat.ML