After handing back exams, I sometimes overhear reactions from the students regarding their grades. For example, “I got an A!!” (said with enthusiasm and pride) or “She gave me an F!” (said with less enthusiasm and anger). It is interesting to note that the attribution of the source of the grade changes depending upon the students’ perceptions of the grades. They “earned” the A, but their professor (me) “gave” them an F.
Taking credit for successes and blaming failures on an external source is not unique to my students. It is a well-established psychological phenomenon known as “self-serving bias.” In fact, it is quite a robust finding in psychological research. We all do it (even college professors).
As humans we tend to think very highly of ourselves. In fact, most of us rate ourselves as “above average” on just about everything! Whether we are assessing our physical attractiveness, intelligence, driving ability, tolerance of others, or sense of humor, we tend to believe that we are better than most. To be clear, we don’t all think we are beauty queens or geniuses….that would be conceited! No, we just believe that we are at the higher end of the scale when it comes to positive qualities relative to other people in the general population.
Of course, it is logically impossible for ALL of us to be above average. By definition, just less than half of us can be. The problem is that we are all sure that WE are in that upper half and that “other people” are in the “average” or “below average” categories….not us.
To demonstrate the concept of self-serving bias to students in my Social Psychology classes, I do a simple demonstration at the start of every semester.* After informing them that the average grade for previous students in the course was a “C+,” I ask them to predict what their final grade will be. I tally the results and use them to teach the concepts of self-serving bias and “unrealistic optimism” (a related phenomenon). Here’s what happens:
If students have realistic expectations about their performance, I would expect a distribution that looks like this:
That NEVER happens! Here is a typical distribution of students’ predictions of their course grades. [These are actual data from one semester, but truly it always looks almost exactly like this. I have the data for most semesters since 2001 if you would like to see it.]
Notice that NO ONE predicts that his/her score will be below average. Heck, no one even predicts the stated average grade of “C+”. All of my students believe that they will receive an above average grade in my course. That has never happened yet, but it’s possible that one of these years I will have a class filled with only above average students. Who knows? Maybe this semester my students will be correct in their predictions!
*Note: This demonstration was not my original idea. Source: Brink, J. “Academic Survey: Social Psychology” (Demo 2-10). In Bolt, M. (1999). Instructor’s Manual to Accompany “Social Psychology” by David Myers.