Vanessa Bohns:

Imagine you need people to donate to a cause you care about. How do you get as many people as possible to donate? You could send an email to 200 of your friends, family members, and acquaintances. Or you could ask a few of the people you encounter in a typical day—face-to-face—to donate. Which method would mobilize more people for your cause?

Despite the reach of email, asking in person is the significantly more effective approach; you need to ask six people in person to equal the power of a 200-recipient email blast. Still, most people tend to think the email ask will be more effective.

In research Mahdi Roghanizad of Western University and I conducted, recently published in the Journal of Experimental Social Psychology, we have found that people tend to overestimate the power of their persuasiveness via text-based communication, and underestimate the power of their persuasiveness via face-to-face communication.

In one study, we had 45 participants ask 450 strangers (10 strangers each) to complete a brief survey. All participants made the exact same request following the exact same script; however, half of the participants made their requests over email, while the other half asked face-to-face.

We found that people were much more likely to agree to complete a survey when they were asked in-person as opposed to over email. These findings are consistent with previous research showing that people are more likely to comply with requests in person than over email.