Firstly they argue that observation of an emergency situation creates an emotional arousal in bystanders. This arousal may be perceived as fear, disgust or sympathy, depending on aspects of the situation.
Costs of helping, such as effort, embarrassment and possible physical harm;Cost of not helping, such as self-blame and perceived censure from others;Rewards of helping, such as praise from self, onlookers and the victim;Rewards of not helping, such as getting on with one's own business and not incurring the possible costs of helping.
Aimed to study bystander behaviour in a natural setting.Also wanted to investigate the effect of four situational variables on helping behaviour or 'Good Samaritanism' :The type of victim.The race of the victim.The behaviour of a 'model'.The size of the group of bystanders.
Four groups of four, containing two males and two females. Female participants observed and recorded the investigation, further away from the incident, while the men were confederates, one was in need and one assisted.