One persuasive tactic I can bet most of us have been exposed to is whereby we are offered free 'tasters' of a product, for example in a supermarket. These offers of free tasters take advantage fo many persuasive techniques; positive mood, reciprocity and evocation of freedom.
Firstly, getting something for free, providing it is not something aversive, is usually a positive outcome. It is positive when offered free food in the supermarket, otherwise people would not approach the opportunity. So inducing a positive mindset in response to the free trial, may induce more positive thoughts about the product. Petty, Schumann, Richman and Strathman (1993) found that positive mood results in persuasion through one of two routes; when we arent moticated to think about an issue, a positive mood directly impacts the positivity of the attitude or when we are motivated to think about an issue, positive mood results in more positive thoughts about the issue, resulting in a positive attitude towards it. So, when we are offered a freebie, and then asked whether we want to purchase the product there and then, the positive mood induced may affect our attitude towards the product, and perhaps persude us to part with our cash.
Secondly, reciprocity may play a role. If someone has given us something, then we feel obliged to repay the favour because we perceive that we are now indebted to the person that gave something to us. Regan (1971) showed reciprocity in a classic study. Participants were to take part in a study, supposedly on art appreciation. Two participants took part at one time, but the real participants did not know that the other was actually Regan's research assistant. They were allowed a short break inbetween two conditions iwthin the experiment, and the confederate seemed to ask the excperimenter whether he could go an dbuy a bottle of Coca Cola. On his return, the confederate handed the participant a bottle, too. Once the experiment was over, the confederate asked the participant whether he would buy some raffle tickets off him. In other conditions, the confederate did not offer the participant a drink. on average, when the confederate had given the participant a drink, the participant bought on average twice the number f tickets that others did who didnt recieve the Coke. This was found regardless of whether the participants actually liked the confederate. Showed massive support for the norm of reciprocity.
Evocation of freedom is another tactic that can be used here. This is whereby you are handed the sample, and asked if you wanted to make a purchase. However, the salesperson will usually reassure you that you dont have to buy the product. Reminding us that we have the choice inthe situation can increase our rate of cmpliance. Guégen and Pascual (2000) found that when freedom was evocated, compliance increased almost 5fold.
Guégen, N., & Pascual, A. (2000). Evocation of freedom and compliance: the 'but you are free of' technique.Current Research In Social Psychology, 5, 264-270.
Regan, D.T. (1971). Effects of a favour on liking and compliance. Journal of Experimental Social Psychology, 7, 627-639.
Petty, R.E., Schumann, D.W., Richman, S.A., & Strathman, A. (1993). Positive mood and persuasion: different roles for affect under high and low elaboration conditions. Journal of Personality and Social Psychology,64, 5-20.