In this week's Statbusters, my column with Andrew Gelman in the Daily Beast, we take note of Slate's recent rant about "wasteful" anti-smoking advertising, and demonstrate how to think about cost-benefit analysis. The key point is: if you are going to make an extreme claim, you better have some numbers to back it up.
These numbers can be approximate, and based on (potentially dubious) Googled data. Not every analysis needs to be super precise.
The column is here.