New psychology research looks at why we help our friends when they need it

(The Conversation is an independent and nonprofit source of news, analysis and commentary from academic experts.)

Authors: Jessica D. Ayers , Boise State University and Athena Aktipis , Arizona State University

Despite how natural friendship can feel, people rarely stop to analyze it. How do you know when someone will make a good friend? When is it time to move on from a friendship? Oftentimes, people rely on gut intuitions to answer these kinds of questions.

In psychology research, there’s no universally accepted definition of a friend. Traditionally, when psychologists have analyzed friendship, it’s often been through the lens of exchange. How much did that friend do for me? How much did I do for them? The idea is that friendships are transactional, where friends stick around