MAASTRICHT , Germany, March 27 (UPI) -- Vindictive people experience more unemployment, have fewer friends and say they are less satisfied with their lives, German researchers say.
Bonn University and Maastricht University researchers said many people are inclined to deal with inequity on a tit-for-tat basis. A person who repays friendly actions in a like manner -- one person does a favor like helping someone move and the favor is returned -- is said to behave with positive reciprocity, and one who avenges unfairness acts with negative reciprocity.
Many people incline to positive reciprocity, others more to negative; others both, the researchers said.
The researchers used socio-economic information gathered by the German Institute for Economic Research in its annual surveys of about 20,000 respondents and found positively reciprocal people tend, on average, to perform more overtime, but only when they find the remuneration fair.
"As they are very sensitive to incentives, they also tend to earn more money," Dr. Thomas Dohmen of Maastricht University said in a statement.
However, the study, published in the Economic Journal, found even pay cuts are not an effective means of bringing negatively reciprocal people back into line -- ultimately the danger arises that they will take revenge -- for example, by refusing to work, or by sabotage, Dohmen said.
Anyone who prefers to act according to the Old Testament motto of "An eye for an eye, and a tooth for a tooth" has, on average, fewer friends and is clearly less than satisfied with his or her life, the researchers said.
