Firms spend billions of dollars each year advertising consumer products in order to influence demand. Much of these outlays are on the creative design of advertising content. Creative content often uses nuances of presentation and framing that have large effects on consumer decision making in...

We measure the causal effects of online advertising on sales, using a randomized experiment performed in cooperation between Yahoo! and a major retailer. After identifying over one million customers matched in the databases of the retailer and Yahoo!, we randomly assign them to treatment and...