A new study finds 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 experiment, 45 participants were instructed to ask 10 strangers to complete a survey. Half the participants made the request over email, and half made it face-to-face. Participants who made requests over email felt just as confident about the effectiveness of their requests as those who made their requests face-to-face, and yet the face-to-face requests were 34 times more effective than the emailed ones.

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.

However, prior to making their requests, we asked participants in each condition to predict how many of the 10 strangers they asked would agree to fill out the survey. Participants in the face-to-face condition guessed that on average 5 out of 10 people would agree. Participants in the email condition guessed that on average 5.5 out of 10 people would agree. This difference was not statistically significant; participants who made requests over email felt essentially just as confident about the effectiveness of their requests as those who made their requests face-to-face, even though face-to-face requests were 34 times more effective than emailed ones.

Why do people think of email as being equally effective when it is so clearly not? In our studies, participants were highly attuned to their own trustworthiness and the legitimacy of the action they were asking others to take when they sent their emails. Anchored on this information, they failed to anticipate what the recipients of their emails were likely to see: an untrustworthy email asking them to click on a suspicious link.

Indeed, when we replicated our results in a second study we found the nonverbal cues requesters conveyed during a face-to-face interaction made all the difference in how people viewed the legitimacy of their requests, but requesters were oblivious to this fact.

If your office runs on email and text-based communication, it’s worth considering whether you could be a more effective communicator by having conversations in person. It is often more convenient and comfortable to use text-based communication than to approach someone in-person, but if you overestimate the effectiveness of such media, you may regularly—and unknowingly—choose inferior means of influence.