Most interesting! The Wikipedia entry for "Bystander effect" claims "These researchers launched a series of experiments that resulted in one of the strongest a

Most interesting! The Wikipedia entry for "Bystander effect" claims "These researchers launched a series of experiments that resulted in one of the strongest and most replicable effects in social psychology." citing Fischer et al https://doi.apa.org/doiLanding?doi=10.1037%2Fa0023304 https://doi.apa.org/doiLanding?doi=10.1037%2Fa0023304 - 'The bystander-effect: A meta-analytic review on bystander intervention in dangerous and non-dangerous emergencies.' The abstract says "In a fixed effects model, data from over 7,700 participants and 105 independent effect sizes revealed an overall effect size of g = –0.35. The bystander effect was attenuated when situations were perceived as dangerous (compared with non-dangerous), perpetrators were present (compared with non-present), and the costs of intervention were physical (compared with non-physical)." but I am unwilling to pay for access to read that paper. Marie R. Lindegaard's publication "Bystander Intervention in Street Violence: Current Evidence and Implications for Practice" from https://osf.io/preprints/socarxiv/7m9uv/download https://osf.io/preprints/socarxiv/7m9uv/download comments "Decades of subsequent research established the bystander effect as one of the best-replicated findings within social psychology (Manning, Levine, & Collins, 2007). Recently, however, this apathetic view of bystanders has been challenged. In a meta-analytical synthesis of the experimentally-based bystander effect research field, Fischer et al. (2011) showed that the bystander effect does not generalize to dangerous emergencies." Wikipedia and Lindegaard both quote Fischer, with rather different interpretations, and the Wikipedia example is clearly more suspect, quoting a 1969 experiment for its example. Thank you for pointing this out! I commented "the story was more parable than fact" to summarize the Genovese case, leaving full discussion up to the Wikipedia article.