LAURA SULLIVAN, host: Online, a good review can make a hotel trendy and a bad one can put a plumber out of a job. It's no wonder that a few businesses are trying to fake us out. And it can be tough for a human to tell a real review from one dreamed up by someone paid to write it. But Jeff Hancock says he's got a computer program that can.

He's a researcher at Cornell University who studies deception, and his team came up with software to unmask fake online reviews.

JEFF HANCOCK: It gets at the very basic idea of what these reviews are about: trust. And as long as there's not so many deceptive reviews, we can continue to use them. But once deception gets too high, it becomes an unusable system.

SULLIVAN: So to develop the software that you did, you essentially trained it on a pool of truthful reviews from online and fake reviews written for the study. And then it went head-to-head against human judges. How did the humans do?

HANCOCK: The humans didn't do very well. And this is consistent with about 40 years of psychological research on deception detection. Our humans got, at best, up to around 60% trying to decide between the two. The computer, on the other hand, could get up to 90% accuracy.


SULLIVAN: Why are we so bad at figuring out when people are lying to us?

HANCOCK: Because we've been lying for as long as we've been talking.


HANCOCK: And that's about 60,000 years. So we have lots of practice.

SULLIVAN: So you've brought along a couple of the hotel reviews you used in the research, the same ones, one fake and one authentic.

HANCOCK: That's right.

SULLIVAN: Can we hear those? And let's see if we can figure it out.

UNIDENTIFIED WOMAN: My husband and I stayed at The James Chicago Hotel for our anniversary. This place is fantastic. We knew as soon as we arrived we made the right choice. The area of the hotel is great. Since I love to shop, I couldn't ask for more. We will definitely be back to Chicago, and we will for sure be back to The James Chicago.

SULLIVAN: OK. So let's hear the second one.

UNIDENTIFIED MAN: I've stayed at many hotels, traveling for both business and pleasure, and I can honestly say that The James is tops. The location is perfect, within walking distance to all the great sights and restaurants. Highly recommend to both business travelers and couples.

SULLIVAN: Oh, wow.


SULLIVAN: The first one kind of bugs me because it keeps using the name of the hotel, which, you know, I don't know if most people would do that. But the second one sounds like such an ad. I mean, there was something about it that just sounds so phony. I...

HANCOCK: So you're going to go with the second one as fake?

SULLIVAN: You know, I don't know. I'm going to go with the first. I don't know why there's...

HANCOCK: All right. You're correct.

SULLIVAN: Really? You're kidding.

HANCOCK: You did it. You did it.


SULLIVAN: Now, what was it about both of those?

HANCOCK: Well, I'll give you one reason. There's a kind of word called a function word: that's the the's and ah's, the prepositions, the pronouns, all the little words. We as humans, we completely ignore those. We don't pay attention to them. We don't think about them when we're producing them.


HANCOCK: And that's one of the things - yeah. That's one of the things we found in this study is that the fake review writers overused first-person reference. And you can hear in that ad that there's - or in that review, that there are quite a few references to herself in there: My family, I love shopping, it's perfect for me, I will be back.

SULLIVAN: So the second one talked generally, but it didn't - he didn't mention himself.


SULLIVAN: That's authentic...

HANCOCK: He didn't mention himself as much, but what he did do is something quite different. And one of the things that is difficult for liars to do is to produce spatial information. You heard in that review he was talking about location to shopping...

SULLIVAN: That's right.

HANCOCK: ...those sort of things.

SULLIVAN: You've done a lot of research about deception on the Internet. Do you - do people lie differently online than they have historically offline to each other?

HANCOCK: I don't think psychologically lying has changed that much. So we see that in online dating, for example, people will lie about their height and weight. And this is not new to the Internet. Men and women have been lying about those sort of things for millennia. What's new, though, is in the past, I would fake my height or weight through, say, clothing. Now online, it's much more of a tell me world rather than a show me world.

SULLIVAN: Jeff Hancock is an associate professor of communication at Cornell University. Jeff, thanks so much for being with us.

HANCOCK: Thank you, Laura. It was a pleasure.

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