In a famous experiment, researchers ran a lottery with a twist. Half the participants were randomly assigned a lottery number. The remaining half were given a blank piece of paper and a pen and asked to write down any number they would like as their lottery number. Just before drawing the winning number, the researchers offered to buy back the tickets. The question researchers wanted to answer is, "How much more do you have to pay someone who 'wrote their own number' versus someone who was handed a number randomly?" The rational answer would be that there is no difference (given that a lottery is pure chance and therefore every ticket number, chosen or assigned, should have the same value). A more savvy answer would be that you would have to pay less for the tickets where the participant chose the number, given the possibility of duplicate numbers in the population who wrote their own number. The real answer? No matter what location or demographic the experiment has taken place in, researchers have always found that they have to pay at least five times more to those who wrote their own number. http://blogs.hbr.org/cs/2012/04/increase_your_teams_motivation.html?awid=8364967012691203781-3271