People who drink too much, have an eating disorder or who take drugs often think that their behaviour is more common than it really is. Initiatives aimed at tackling drinking in college have tried to point out that most students drink much less than their peers think they do - and these intiatives can change drinking behaviour. Researchers from the University of Washington interviewed 124 wife-batterers enrolled on a treatment programme to see if they too overestimated how common their behaviour was. They were asked how prevalent they thought various different types of abusive behaviour were and their answers were compared with the actual frequency of such abuse. The participants overestimated how frequent this behaviour was; they thought that 27.6% of men had thrown things at their partner when 'only' 11.9% have done this in reality and they also overestimated the frequency of marital rape - 23.6% vs 7.9%. However, it is not clear whether the men's overestimation of the frequency of this behaviour made them more likely to commit it, or whether the fact that they abused women led them to think that maltreating them was more common than it really is.
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