We implement a regression discontinuity design using the continuous raw Advanced Placement (AP) exam scores, which are mapped into the observed 1-5 integer scores, for over 4.5 million students. Earning higher AP integer scores positively impacts college completion and subsequent exam taking. Specifically, attaining credit-granting integer scores increases the probability that a student will receive a bachelor’s degree within four years by 1 to 2 percentage points per exam. We also find that receiving a score of 3 over a 2 on junior year AP exams causes students to take between 0.06 and 0.14 more AP exams senior year.
Smith, Jonathan, Michael Hurwitz, and Christopher Avery. "Giving College Credit Where It Is Due: Advanced Placement Exam Scores and College Outcomes." HKS Faculty Research Working Paper Series RWP15-021, May 2015.