Seeing is Deceiving? AI-Manipulated Images and Protest Size Estimates

The size of the crowd at large political protests is a highly politicized number, as it is often interpreted as the level of popular support. Not surprisingly, it is in the interest of political actors to manipulate perceptions of the crowd size, to boost support for or to delegitimize a particular political issue. This paper examines how perceptions of the crowd size can be manipulated using AI-generated protest images. In an experiment, participants are asked to rate the size of the protest crowd from a series of social media images. These images are manipulated to display larger (or smaller) crowd sizes using a generative image model. Results show that manipulation works, and that AI-inflated (or reduced) crowd portrayals lead to higher (or lower) crowd estimates as compared to the unmodified images. These results demonstrate the effectiveness of AI-generated visual content in shaping popular perceptions of mass protests on social media.