arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2402.14979cs.LGcs.CLstat.ME
收藏

针对人类偏好优化语言模型是一个因果推断问题

Optimizing Language Models for Human Preferences is a Causal Inference Problem

Carnegie Mellon University(卡内基梅隆大学)

Victoria Lin, Eli Ben-Michael, Louis-Philippe Morency

AI总结:

本文将语言模型的人类偏好优化形式化为因果推断问题,提出因果偏好优化(CPO)及其双重稳健扩展DR-CPO,以无偏且低方差的方式优化大语言模型,并通过实验验证其有效性与稳健性。

摘要:

随着大语言模型(LLMs)在学术和商业环境中的应用日益广泛,人们对能够让语言模型生成符合人类偏好文本的方法越来越感兴趣。本文对基于直接结果数据集进行面向人类偏好的语言模型优化进行了初步探索,其中每个样本由一个文本和一个衡量读者反应的关联数值结果组成。我们首先提出,语言模型优化应被视为一个因果问题,以确保模型正确学习文本与结果之间的关系。我们将这一因果语言优化问题形式化,并开发了一种方法——因果偏好优化(CPO),该方法求解该问题的一个无偏代理目标。我们进一步将CPO扩展为双重稳健CPO(DR-CPO),在保持对偏差可证明的强保证的同时,降低代理目标的方差。最后,我们通过实验证明了(DR-)CPO在直接结果数据上优化最先进的大语言模型以符合人类偏好的有效性,并验证了DR-CPO在困难混杂条件下的稳健性。

英文摘要:

As large language models (LLMs) see greater use in academic and commercial settings, there is increasing interest in methods that allow language models to generate texts aligned with human preferences. In this paper, we present an initial exploration of language model optimization for human preferences from direct outcome datasets, where each sample consists of a text and an associated numerical outcome measuring the reader's response. We first propose that language model optimization should be viewed as a causal problem to ensure that the model correctly learns the relationship between the text and the outcome. We formalize this causal language optimization problem, and we develop a method--causal preference optimization (CPO)--that solves an unbiased surrogate objective for the problem. We further extend CPO with doubly robust CPO (DR-CPO), which reduces the variance of the surrogate objective while retaining provably strong guarantees on bias. Finally, we empirically demonstrate the effectiveness of (DR-)CPO in optimizing state-of-the-art LLMs for human preferences on direct outcome data, and we validate the robustness of DR-CPO under difficult confounding conditions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑