Perception bias: how official statistics shape attitudes towards immigrants

Drawing on the Intergroup Competition Hypothesis and the Intergroup Threat Theory, this study examines whether correcting misperceptions about the size of the foreign population affects attitudes towards migrants. Specifically, it assesses the impact of providing corrective statistical information about the share of children born to families with at least one immigrant parent and about how this share changed over the past 25 years. The research relies on a large-scale multi-arm survey experiment (n = 2,000) conducted in Italy in 2024, a country increasingly characterised as a migration state. Participants first estimated the current share of children with a migrant background and its change over time. One treatment group received accurate information about the current share of these children, while another received information about its increase over time. After treatment, all respondents, including both treatment and control groups, answered a series of questions measuring different dimensions of attitudes towards migrants and their children. The results show, with few exceptions and some instances of backlash, that individuals tend to resist revising their attitudes towards migrants even when presented with corrective statistical information.