People who believe the world is a just place trust salespeople¹ more than consumers who don't -- but only after they've made a purchase, according to a new study in the Journal of Consumer Research. "As consumers, we make many decisions each day that may or may not turn out the way we hope. Since we know salespeople may have their own reasons for the advice and recommendations they give, trusting a salesperson² may put us at further risk of making a bad decision," write authors Andrew E. Wilson (Saint Mary's College of California) and Peter R. Darke (York University).

The authors examined how consumers balance the tension between trust and protecting themselves from making bad decisions. For example, in one study, they asked participants to choose between two digital cameras that a salesperson had recommended. Half the participants told the researchers how much they trusted the salesperson before they made their choice; the other half rated their trust after the made their choice. The authors asked all the participants to tell them how much they believed their personal world was a place where they generally got what they deserved. "Our data analysis shows that after making a choice, individuals who believed in a just world trusted the salesperson more than those who did not hold this belief," the authors write. Before making the choice, both groups trusted the salesperson equally, which demonstrates that people use their belief in a just world to cope with the possibility of having made a bad decision.

In another study, the authors manipulated worldviews and found that optimism also led to increased trust in salespeople after purchase decisions, but only when participants did not detect an ulterior motive³（隐秘不明的动机） in the salesperson.

Finally, in a third study, the authors discovered that the coping mechanism⁴ they studied only occurred when consumers were considering their own purchases, not others'. They also found that consumers who showed "optimistic trust" ended up more satisfied with their purchase decisions.

"Consumers who believe they live in a just world use this belief as a resource in coping with the difficulty of making consumer decisions, and this has the somewhat surprising effect that they end up trusting salespeople more following a choice," the authors conclude.