In his book 59 Seconds Professor Richard Wiseman writes about another experiment in 1970s, in which psychologist Dennis Regan invited volunteers to an art gallery to help rate paintings on show. In the gallery they met an assistant, who showed them around. In half of the cases, the assistant brought a volunteer a bottle of cola from a free drinks table. In other cases, the assistant only helped himself. At the end of the tour, the assistant asked a volunteer to buy some raffle tickets from him, priced at 25c, explaining that he only had a handful left and that he would win a $50 prize if he sold out: “Any would help, the more the better.” Even though the cola came from a free drinks table and did not cost the assistant anything, the small gesture of offering a drink prompted volunteers to buy twice as many raffle tickets than those who weren’t given refreshments.
Both studies show that apparently spontaneous acts of favour elicit a need to reciprocate.
Another effective experiment, described by Professor Wiseman, was published in the Journal of Applied Social Psychology in 2002 by Strometz, Rind, Fisher and Lynn: “Sweetening the Till: The Use of Candy to Increase Restaurant Tipping.” During the experiment waiters in a restaurant were instructed to hand customers their bills with or without sweets. The group of customers, given a single sweet per person, tipped 3% more than the control group, which did not received any sweets. Customers who received two sweets each, tipped 14% more than the control group. Finally, in the fourth group, customers received a bill with one sweet each but then, as waiters were turning away from the table, they reached into their pockets and handed each customer a second sweet. The customers ended up with two sweets each as in the other group, but the ‘spontaneous' gesture delivered a much more powerful effect, resulting in tipping increased by 23%.
Psychologists are fascinated by reciprocity or back-scratching. It only takes a simple gesture (of offering a free drink or handing out a couple of sweets) to induce someone to buy raffle tickets or leave a generous tip. We like to help people we like. To put it differently, if you want to help yourself, perhaps it is worth offering to help others first.
Professor Wiseman remarks that not all favours result in reciprocity. “Favours have their strongest effect when they occur between people who don’t know each other very well, and when they are small but thoughtful. When people go to a large amount of effort to help someone else, the recipients can often feel an uncomfortable pressure to reciprocate."
Morris, Podolny and Ariel (2001) also wrote about “Culture, Norms and Obligations: Cross-National Differences in Patterns of Interpersonal Norms and Felt Obligations Toward Co-Workers”. "Americans were heavily influenced by the reciprocity rule (‘Has this person helped me in the past?’), Germans were more concerned about whether their actions would be consistent with company rules, the Spanish were driven more by basic rules of friendship and liking, and the Chinese were swayed by the status of the co-worker.”