 In a critique of the Cialdini et al. paper, Batson, Sager, et al. (1997) used three measures of self-other merging. One was the IOS Scale used by Cialdini et al. The second was a “perceived similarity” task in which “[p]articipants were asked, ‘How similar to you do you think the person …is?’ (1 = somewhat, 9 = extremely)” (1997: 500). In the third, participants rated both themselves and the target on a series of personal attributes. The “measure of merging was the mean absolute difference between ratings of self and other” (1997: 498).