TY - RPRT AU - Askitas, Nikos TI - The Behavioral Signature of GenAI in Scientific Communication PY - 2025/Aug/ PB - Institute of Labor Economics (IZA) CY - Bonn T2 - IZA Discussion Paper IS - 18062 UR - https://www.iza.org/publications/dp18062 AB - We examine the uptake of GPT-assisted writing in economics working paper abstracts. Using data from the IZA DP series, we detect a clear stylistic shift after the release of ChatGPT-3.5 in March 2023. This shift is evident in core textual metrics—mean word length, type-token ratio, and readability—and reflects growing convergence with machine-generated writing. While the ChatGPT launch was an exogenous shock, adoption is endogenous: authors choose whether to use AI. To capture this behavioral response, we combine stylometric analysis, machine learning classification, and prompt-based similarity testing. Event-study regressions with fixed effects and placebo checks confirm that the change is abrupt, persistent, and not explained by pre-existing trends. A similarity experiment using OpenAI’s API shows that post-ChatGPT abstracts resemble their GPT-optimized versions more closely than pre-ChatGPT resemble theirs. A classifier, trained on these variants, flags a growing share of post-March 2023 texts as GPT-like. Rather than suggesting full automation, our findings indicate selective human–AI augmentation. Our framework generalizes to other contexts such as e.g. resumes, job ads, legal briefs, research proposals, or programming code. KW - AI-assisted writing KW - linguistic metrics KW - event study KW - machine learning KW - natural language processing (NLP) KW - text analysis KW - academic writing KW - GPT adoption KW - diffusion of technology ER -