As observed throughout 17 ECON0110 (Principles of Economics) lectures:
One cough has the negative externality of inciting a rapid succession of coughs (up to two dozen) throughout the lecture hall. This chorus of coughs, in turn, produces the additional negative externality of preventing the scores of attentive students from hearing the lecture. This tends to occur during the first half of the spring semester, with several of these “bursts” per 50 minute lecture.
The most interesting aspect of the Cough Principle of Economics Lectures is that it, at least in my research, is exclusive to economics courses. Other large lectures tend to have a much lower coughing rate, so what makes barking so much more prevalent in Econ? Maybe it’s because it’s so early in the morning. Or maybe it’s Professor Friedberg’s tendency to use cigarettes as an example. Most likely, however, everybody is just cough-cursing N. Gregory Mankiw’s tendency to assert the general ineffectiveness of most government regulations — coughBushAdministrationcough. How can we solve this problem? Internalize the externality, of course! Hold that cough in or get yourself some Halls (or the perfect substitute CVS brand). For further confirmation of this phenomenon, a blogger at Princeton observed a similar situation in her ECO101 class.