The Measure of All Things Finding Out That Something Doesn't Work Is the First Step Toward Learning What Does Work

Duncan Watts shares insights from his new book Everything is Obvious, including a recent randomized experiment testing online advertising with 1.6 million Yahoo! users. The researchers estimated that the additional revenue generated by the advertising was roughly four times the cost of the campaign in the short run, and possibly much higher over the long run. But what they also discovered was that almost all the effect was for older consumers-the ads were largely ineffective for people under 40. At first, this latter result seems like bad news. But the right way to think about it is that finding out that something doesn't work is also the first step toward learning what does work.