Why Do We Reward Giving, but Not Giving Effectively?

Post by Amanda McFarlan

What's the science?

The concept of donating is one with which we are all familiar, and yet, very few of us actually take the time to think about the effectiveness of our giving. One potential explanation for this is that giving evolved to be mainly driven by social rewards - rewarding behaviours that are easily defined and observed. Thus, the efficacy and impact of donating, which are not easily defined or observed, may not have evolved to be important factors to consider when deciding to donate. This week in Nature Human Behaviour, Burum and colleagues performed a total of five studies to demonstrate that the social rewards associated with giving are sufficient to encourage people to give, but not to give effectively.

How did they do it?

In the first study, participants were divided into two groups, and each given a 30-cent bonus. The first group of participants was given the option of donating all, some, or none of their bonus to a charity of their choosing, while the second group of participants was given the option of saving all, some, or none of their bonus to receive later. In both groups, the amount of money donated or saved would be matched by a factor of 1 to 10. 

In a second study, participants were asked what percentage of their income they would be willing to donate in order to prevent one stranger, five strangers, one family member, or five family members from starving for a year. Participants in the third, fourth and fifth studies were matched with a donor who had selected their favorite charity from a list and was given the choice to keep or donate all of a bonus to that charity, varying with each study. In the third study, the donor was given the choice to donate all or some of a bonus that would either be matched (1:1) or not. In the fourth study, the donor had the same choice to keep or donate all of a bonus, but this time the participants were told that the bonus was either 10 cents or 20 cents. In the fifth study, the donor received a bonus of either 75 cents or 90 cents and was given the choice to donate one of several amounts. Participants were always matched with a donor who donated 60 cents. After reading about the donor’s decision, participants were given a 30-cent bonus and were given the option to reward the donor with some or all of their bonuses. Participants were also asked to rate the donor on characteristics including how generous, giving, good a person, ethical, moral, and deserving of praise they were. 

What did they find?

In the first study, the authors found that participants responded to efficacy when saving, but not when donating to charity. Matching the donation by a factor of 1 to 10 did not have an effect on the amount the participants donated, but it did have a significant effect on the amount they saved. In the second study, the authors showed that participants donated effectively when helping their family members, but not when helping strangers. Participants were willing to donate substantially more when helping family members compared to strangers. They were also willing to donate more when five family members were in need compared to one family member, while the amount they were willing to donate to strangers was similar regardless of the number of people in need. 

Next, the authors showed that in the third, fourth, and fifth studies, the donors who chose to donate were rewarded more by the participants than the donors who did not choose to donate. Notably, the authors found that the participants did not reward the donor more if their donation was larger, whether they donated a small or large bonus, or if the donor gave a larger portion of their total bonus. The participants’ character assessments of the donors mirrored these results such that donors that chose to give were seen as generous, but donors who gave more were not seen as more generous than donors who gave less.

What’s the impact?

This study demonstrates that people do not attend to efficacy when donating to charity but are capable of attending to efficacy in situations that are not dictated by social rewards, such as saving for the future and helping family members. Additionally, people are insensitive to the impact of giving. All together, these findings support the notion that donors evolved to be sensitive to clearly defined behaviors that bring social rewards.

Burum et al. An Evolutionary Explanation for Ineffective Altruism. Nature Human Behaviour (2020). Access the original scientific publication here.