Logically, the percentage of work that each team member contributes to a team project cannot add up to more than 100%. For example, if both authors of an academic paper insist that they did 75% of the work, the total work accomplished would be 150%. The inescapable conclusion is that one or both of them is over-claiming his or her contribution.
In a series of four experiments, Eugene M. Caruso and Nicholas Epley from Chicago-Booth School of Business and Juliana Schroeder from Berkeley’s Haas School of Business found that over-claiming is rampant in research teams — and the greater the number of contributors, the more contributors over-claim.
Their study confirms that individuals typically (but not intentionally) overestimate their contributions to team projects, especially if the teams are large. Managers trying to gauge the contribution of different team members — for reward or other purposes — should recognize when over-claiming is more likely, and use different strategies to remind individuals of the contributions of others.
In every case, the results were the same: the larger the group, the more over-claiming occurred. For example, in one experiment, the sum of contribution by MBA students in groups of 8 or more reached 140%, compared to approximately 105% for groups of less than four students.
The researchers believe that over-claiming is not done for egotistical reasons (e.g. to gain more credit); instead, egocentricity (focusing on oneself and forgetting about others) is to blame. This conclusion is supported by the decrease in over-claiming that occurs when team members are asked to list the contributions of the other members of the team or even, as in some experiments, when they are simply asked to give the names of the other team members. Egotists would still claim more credit; egocentrics are reminded about the contributions of others.
Asking employees working in a group to self-evaluate their contribution can be dangerous. The larger the group, the greater the danger that people will over-claim how much credit they should receive for the success of the overall group. There may be situations when such an evaluation is needed. Perhaps you are considering a person for a promotion and want an idea of how much they contributed to an important group project. Or perhaps there is a reward for a group’s success that you want to allocate based on individual contribution.
This study shows that even without an incentive, and without malice, individuals tend to be focused on how much they have contributed — which leads to over-claiming. Therefore, any self-evaluation should be taken with this in mind, especially in larger groups. And simply asking people to include every member’s contribution in their evaluation can make a difference. There may still be some over-claiming, but you are closer to the truth.
Many Hands Make Overlooked Work: Over-Claiming of Responsibility Increases with Group Size. Juliana Schroeder, Eugene M. Caruso & Nicholas Epley. Journal of Experimental Psychology: Applied (February 2016).