Better answers, broader thinking: What students gain from ChatGPT and critical-thinking training

A randomized experiment involving 1,000+ first-year undergraduates at Bocconi University, conducted with OpenAI Economic Research, tested the separate and combined effects of ChatGPT access and critical-thinking training on a real-world marketing assignment. Students with ChatGPT access scored nearly one full point higher on a five-point rubric, producing more expert-like, logically coherent work, while a causal-reasoning exercise independently drove greater idea originality and diversity without improving rubric scores. Students receiving both interventions captured gains across the widest range of measured outcomes, demonstrating complementary rather than competing effects. The findings challenge traditional evaluation rubrics, which reward polished outputs but fail to capture originality or reasoning depth—qualities that become more strategically important as AI lowers the cost of producing professional-quality work.