🤖 AI Summary
This study addresses a critical gap in current evaluation methods, which focus solely on final answer accuracy while overlooking how models identify and annotate biased content during reasoning, thereby creating blind spots in accountability assessment. To remedy this, the authors propose a fine-grained diagnostic framework based on reasoning traces that evaluates model behavior along two dimensions: bias sensitivity and bias acknowledgment—the latter being a novel metric introduced in this work to measure whether a model explicitly flags biased content within its Chain-of-Thought reasoning. By integrating human-defined surface indicator rules, the framework enables automated analysis of reasoning trajectories. Experiments on GSM8K reveal that while GPT-4o and Claude Sonnet 4 exhibit comparable bias sensitivity, their bias acknowledgment rates differ markedly at 13.0% and 75.0%, respectively, highlighting substantial disparities in responsible reasoning capabilities.
📝 Abstract
Reasoning models are increasingly used in settings where the final answer is not the only object of review: educational tools may show students intermediate steps, decision-support systems may require human oversight, and audit workflows may inspect traces for misleading or biased input. In such settings, two responses can receive the same final-answer score while differing in whether the trace explicitly flags injected biasing content. Accuracy-only evaluation collapses these cases. We study this gap as a measurement blind spot for responsible evaluation and introduce a minimal trace-level diagnostic with two axes: \emph{susceptibility} (whether the bias breaks a previously correct answer) and \emph{acknowledgment} (whether the trace contains a rubric-defined surface reference to the injected content). Across thousands of biased GSM8K trials, GPT-4o and Claude Sonnet~4 have similar susceptibility rates ($1.3\%$ vs.\ $1.2\%$) but substantially different acknowledgment rates ($13.0\%$ vs.\ $75.0\%$) under the same rubric.