Challenges in Measuring Bias via Open-Ended Language Generation

Abstract: Researchers have devised numerous ways to quantify social biases vested in pretrained LLMs. As some LLMs are capable of generating coherent completions given a set of textual prompts, several prompting datasets have been proposed to measure biases between social groups -- posing language generation as a way of identifying biases. In this opinion paper, we analyze how specific choices of prompt sets, metrics, automatic tools and sampling strategies affect bias results. We find out that the practice of measuring biases through text completion is prone to yielding contradicting results under different experiment settings. We additionally provide recommendations for reporting biases in open-ended language generation for a more complete outlook of biases exhibited by a given LLM. Code to reproduce the results is released under https://github.com/feyzaakyurek/bias-textgen.