Sharing, selling and the things-in-common touch

People are more likely to buy things from a salesman if they feel they have something in common with him. In one study researchers from the University of British Columbia and the INSEAD business school in Singapore found that people were more likely to enjoy a fitness programme and buy personal-training sessions from a personal trainer if they shared a birthday with him. In another study people who found that they were born in the same place as their dentist were happier with their care and more likely to book another appointment with the same clinic. Sociable people were more likely to be influenced by this effect than less-sociable ones.

http://www.sciencedaily.com/releases/2009/07/090720163749.htm