Alex Tabarrok defends online education:
The importance of leverage was brought home to me by a personal anecdote. In 2009, I gave a TED talk on the economics of growth. Since then my 15 minute talk has been watched nearly 700,000 times. That is far fewer views than the most-watched TED talk, Ken Robinson’s 2006 talk on how schools kill creativity, which has been watched some 26 million times. Nonetheless, the 15 minutes of teaching I did at TED dominates my entire teaching career: 700,000 views at 15 minutes each is equivalent to 175,000 student-hours of teaching, more than I have taught in my entire offline career. Moreover, the ratio is likely to grow because my online views are increasing at a faster rate than my offline students.