Understanding the inventor team size: A view from “The Rice Theory”

The inventor is a vital input in acquiring new technologies. Collaboration among inventors is an essential topic for scholars. Talhelm et al. proposed The Rice Theory, highlighting the cultural differences between rice and wheat regions. This paper explores the differences in inventor team size under rice and wheat cultures using invention patent data in China. The results of ordinary least square estimation and instrumental variable estimation indicate that the size of inventor teams under rice culture is significantly smaller than that under wheat culture by 0.558–0.721 persons. Using the Chinese Qinling–Huaihe line, this paper constructs a regression discontinuity (RD) design. The local average treatment effect estimation confirms the difference in rice and wheat cultures. Subsequently, we demonstrate the significant existence of this difference through lots of robustness checks. We try to explain the phenomenon from the perspective of “The Rice Theory” by arguing that inventors in rice regions may be more inclined to collaborate but with a smaller inventor team size. This paper demonstrates the cultural differences in the performance of inventor team size, informing our understanding of input in research and development (R&D) activities.