The reciprocity norm is when you expect that someone will treat you the way you treated them. As the book puts it “people will help, not hurt, those who have helped them.” This is one norm that I live by and never really thought about. In other words, the reciprocity norm is the same as ‘The Golden Rule’ that I learned about in Elementary school.
My example comes from Big Bang Theory. Here’s the video: (The first 45 seconds are the important part).
In the video, Penny gives Sheldon a gift and Sheldon is upset about it. He explains to Penny that because she gave him a gift he is now required to also get her a gift. The reciprocity norm could be shown in the following equation in regards to the example. Someone (Sheldon) will treat you (give you a gift) the way you (Penny) treated them (gave Sheldon a gift).