Kahneman's framing experiment showed that people make different decisions based on how information is presented or "framed". When treatments for saving lives were framed positively, people chose the secure option, but when framed negatively in terms of deaths, they chose the risky option. Zajonc's mere exposure study found that repeated exposures to a stimulus increases people's positive feelings towards it. Regan's reciprocity experiment demonstrated that people feel obligated to return favors, so providing customers value increases the chance they will purchase products.