A second possible argument is that, although the coefficient for atten-
dance is significant, it is quantitatively small. Our results indicate that
the estimated effect of attendance can be considered quantitatively relevant:
missing one lecture is associated to about a half percentage point drop in
test score. The opportunity cost of missing lectures is relevant not only in
absolute terms but also in relative terms: the return to each hour of self-
study is substantially lower than that to each hour spent attending lectures
or classes. In assessing the size of the estimated coefficient for attendance we
should also consider that measurement error, due to the self-reported nature
of attendance, is likely to produce a downward bias in the estimate of its ef-
fect on performance. In addition, to the extent that regressors such as grade
point average and exam speed reflect the effect of attendance in other courses
(and that attendance is positively correlated across courses), the inclusion
of these variables could lead to underestimate the effect of attendance on
performance in Introductory Microeconomics.
Summing up, can we conclude that we, as academics, are doing some-
thing useful for student learning? According to the results of this study, yes.
Alternative educational schemes, such as e-learning, would imply a positive
and significant cost in terms of the quality of student learning. When con-
sidering the introduction of alternative educational models, the benefits of
distance learning in terms of cost reduction for suppliers and time saving for
students should be carefully weighted against the loss for student learning.
Should then anything be done to increase attendance? Maybe yes. We find
that the costs of absenteeism are significant and quantitatively relevant. In
addition, we should consider that absenteeism implies not only a direct nega-
tive effect on learning, as reported in this study, but also significant negative
externalities, such as the nuisance to the rest of the class and the high costs
to the lecturer outside class.27
Does this mean that attendance should be made compulsory? Definitely
not. A compulsory attendance policy would distort the opportunity cost of
absenteeism and impose a welfare loss on students.28 In addition, besides the
fact that a captive audience is not a good learning environment, compulsory
attendance would take away an important signal for lecturers on the quality
27See Brauer (1994).
28As observed by Deere (1994), a compulsory attendance policy would contradict many
of the principles typically taught in introductory economics courses: “While students may
not always make the wisest use of their time, it seems rather arrogant to suggest that we
faculty know better the value of our sub ject just because we know our subject”.
17