Microtargeting works, just not the way people think

In politics, tailored ads make sense, but with real limits to the tailoring. Recent U.S. elections have raised the question of whether "microtargeting," the use of extensive online data to tailor persuasive messages to voters, has altered the playing field of politics. Now, a newly-published study led by MIT scholars finds that while targeting is effective in some political contexts, the "micro" part of things may not be the game-changing tool some have assumed. "In a traditional messaging context where you have one issue you're trying to convince people on, we found that targeting did have a substantial persuasive advantage," says David Rand, an MIT and co-author of the study. Indeed, the study found that tailoring political ads based on one attribute of their intended audience - say, party affiliation - can be 70 percent more effective in swaying policy support than simply showing everyone the single ad that is expected to be most persuasive across the entire population. But targeting political ads using multiple attributes - for instance, ideology, age, and moral values - did not add any further benefit, in the study. "We didn't find much evidence that microtargeting works," says Rand, who is the Erwin H. Schell Professor at the MIT Sloan School of Management.