“In line with this scenario, students expecting a graded test increased their confidence and absolute accuracy of confidence judgments to a greater extent from mid-term to final test than students expecting a pass-fail test (Study 1 and 2). Moreover, the graded group decreased the bias of their confidence judgments more than the pass-fail group. Consequently, the graded students outperformed the pass-fail students on these measures in the final tests in all three studies.” (p.138)
Barenberg, J., & Dutke, S. (2013). Metacognitive monitoring in university classes: anticipating a graded vs. a pass-fail test affects monitoring accuracy. Metacognition and Learning, 8(2), 121–143. doi: 10.1007/s11409-013-9098-3