English: Median cumulative productivity in a group of productive Wikipedians who randomly received a barnstar (red) and a control group (blue). Cumulative productivity is measured as the running total number of post-treatment edits to encyclopedic articles divided by the total number of such edits made during the 30 days prior to the treatment for each subject. The treatment was given on day 0 (vertical line). By the end of the 90-day observation period, subjects in the experimental group exhibited a median productivity that was 2.94 times their pre-treatment total versus 2.21 in the control group, for a post-treatment difference of 60%. Also shown are additional awards received by subjects from third-parties after the treatment. Twelve subjects in the experimental condition received a total of fourteen awards, whereas two subjects in the control condition received a total of three awards.