Jennjou Chen (National Chengchi University) & Tsui-Fang Lin (National Taipei University) have posted Class Attendance and Exam Performance: A Randomized Experiment on SSRN.  Here is the abstract:

The study of determinants of a college student’s academic performance is an important issue in higher education. Among all factors, whether or not attending lectures affects a student’s exam performance has received considerable attention. In this paper, we conduct a randomized experiment to study the average attendance effect for students who have chosen to attend lectures, which is the so-called the average treatment effect on the treated in program evaluation literature. This effect has long been neglected by researchers when estimating the impact of lecture attendance on students’ academic performance. Under the randomized experiment approach, least squares, fixed effects, and random effects models all yield similar estimates for the average treatment effect on the treated. We find that, class attendance has produced a positive and significant impact on students’ exam performance. On average, attending lecture corresponds to a 7.66% improvement in exam performance.