“…Indeed, several studies show based on multivariate regressions that persons with comparatively low socio-economic resources can be mobilized through cash incentives (Becker et al, 2019;Göritz, 2008;Göritz & Luthe, 2013;Schröder et al, 2013) and lotteries (Göritz & Luthe, 2013). Other studies, however, find no statistically significant demographic differences between various incentive groups (Becker & Mehlkop, 2011;Suzer-Gurtekin et al, 2016). Gajic et al (2012), for example, do not find statistically significant differences in characteristics like gender, education, or household income in mean comparisons.…”