What qualifies as fair in each of these situations may be different, of course. Children often see fairness as equal treatment. If one child gets a larger slice of cake than another, then you can almost guarantee cries of "That's not fair!" In a work setting, though, we don't expect everyone to be paid the same amount. Instead, it seems fair if each person is paid in proportion to their effort or their value to the company.

A fascinating paper in the December, 2011 issue of the Journal of and Social Psychology by Shoham Choshen-Hillel and Ilan Yaniv explores another factor that influences judgments of fairness-who is in charge.

When psychologists talk about whether someone is in control of their situation, they talk about agency. A person with high agency controls their destiny. A person with low agency is at the mercy of others for their situation.

The research in this paper demonstrates that when people have a low degree of control over their situation, they tend to favor equal divisions of resources. When they have a high degree of control, they tend to favor options that give the best possible outcome for everyone concerned, even if they don't benefit as much as others do.

In one study, they had participants perform a task in which they had to estimate the prices of a variety of products. It took about 10 minutes to complete the task, at which point the participants were paid about $3 for their time. (The study was done in Israel, so participants actually received 10 Israeli shekels.)

Participants were then told that another person was also going to do the same task. Those in the low agency version of the study were then asked whether they would be more satisfied if the other participant received the same amount of money for completing the task (10 shekels) or more money for completing the task (20 shekels). People were about evenly split between the two options. That is, about half the people wanted the other person to get the same amount of money as they did, while the other half would be happiest if the other person actually got paid more than they did.

Participants in the high agency version of the study were told that they could decide whether the other person doing the task would get the same amount of money (10 shekels) or more (20 shekels). In this case, over 80% of the people in the study said that the other person should get more. That is, when people had control, they wanted the outcome that would give the most combined benefit.

In another version of the study, the researchers found that high agency even led people to pick options that gave the greatest combined benefit when it would leave them with a lower payment overall. In this study, one option was that the participant would get 11 shekels, while the other person would get 10. The second option was that the participant would get 10 shekels (less money), but the other person would get 20.

Participants who had no control over this situation generally preferred the option where they got slightly more money than the other person. Those who could control the payment, though, generally preferred the option where they got less money, but the pair got more money overall.

This is a fascinating finding. It suggests that when a group wants to maximize its overall gain, it is important to give everyone some control over how resources are allocated. In this case, people will be most likely to accept an outcome that benefits the group most, even if they themselves don't get as much of the pie as others do.

Of course, it will be important to see how well these findings extend to more real-world situations with higher stakes. After all, in these studies people were being paid between $3 and $6. People might feel differently if the sums of money were larger.

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