BIAS OF THE WEEK

Reciprocity

Participants in a study were unexpectedly offered a drink by an accomplice. They were then asked to buy lottery tickets by the same accomplice. 

The results showed that those who had received the drink were more likely to buy tickets than those who had not.

We are more likely to respond favorably to a request when we have received a favor from the person making the request.

See the full study here :

Dennis T. Regan (1971). Effects of a favor and liking on compliance. , 7(6), 0–639. doi:10.1016/0022-1031(71)90025-4 

Want to know more about biases?

Negavity Bias

Reactive devaluation

Take-the-best Heurisitc

Pratfall Effect