This paper studies the influence mechanism of grassroots public service supply on local private economic vitality. Aiming at the problem that the existing research has a coarse description of the role path and insufficient utilization of unstructured governance data, this paper constructs a multi-source data system composed of public service statistical indicators, government affairs platform operation records and enterprise feedback texts, and combines text mining, feature fusion and interpretable machine learning methods to carry out mechanism identification. The research is based on 4576 valid samples from 286 districts and counties from 2021 to 2024. The results show that the local private economic vitality index rises from 0.418 to 0.641, the growth rate of new establishment of private enterprises rises from 4.9% to 12.3%, the enterprise survival rate rises from 71.6% to 84.7%, and the innovation input intensity rises from 2.8% to 5.0% when the level of grassroots public service supply rises from low to high. Among them, the impact of government service efficiency and digital public information service is more prominent, with the average contribution of 27.4% and 22.1% respectively. Research shows that the improvement of grassroots public services can continuously enhance the vitality of local private economy by reducing institutional transaction costs, enhancing information availability and stabilizing business expectations.
