I am doing research on students and their perception of their grades. Specifically, I want to do an experiment where students either (a) see their actual grades in a course (as a percentage) - the control condition or (b) their actual grades in a course (as a percentage) as well as their percentile in the class - the treatment condition. For example, a student could be earning a 90% in the class (as a percentage) but be in the 99th percentile for their class. The key question of interest is whether seeing the percentile information influences students motivation etc.
However, I was wondering about treatment interference. That is, the percentile information in the treatment condition is dependent. If one student is in a higher percentile, that necessarily means that another student in the class is in a lower percentile. With this in mind, is my experiment valid? Is there any ways I can get around this problem? I want to be sure I'm drawing the correct causal interpretation.