Sunday, February 25, 2007

The lexical patterns of liars

If you’re emailing a teacher with excuses for not being at a lesson, not giving in coursework or being late, and you’re telling porkies, beware; new software has been developed which can – according to this article in The Sunday Times - spot lies through your lexis.

The software has been designed by a team at Cornell University led by Jeff Hancock, and scans messages to discover a number of lexical patterns and trends, which might indicate that the writer is lying, with a 70% success rate so far.

One of the main giveaways is the length of a message. E-mails that mask a lie have, on average, 28% more words than truthful messages. “When you’re lying, you are trying to give a credible story so you provide more detail, you are in persuasive mode,” said Hancock.

Liars are also more likely to use third-person pronouns, such as “they” and “he”, in a bid to distance themselves from a lie because of the guilt associated with it.

“People also tend to use negative emotional terms because they feel uncomfortable when they are lying,” said Hancock. “So they tend to use terms like ‘sad’, ‘angry’, ‘unhappy’ and ‘stressed out’.”

Another telltale sign of a fib is the overuse of “sense terms”, such as “see”, “feel” and “touch”, which Hancock believes are employed to build up an elaborate and evocative account of a scenario that may never have happened.

Finally, liars tend to use fewer “causal phrases” to minimise the chances of being caught out. So, for example, a person conducting an illicit affair is less likely to say they were unable to get home early last night because they were with someone else. “They will just say, ‘Sorry, I couldn’t meet you’ and be deliberately vague,” said Hancock.

Email is often described as a blunt tool, which doesn’t convey the nuances and tones of real face to face conversation, and it’s often blamed for misunderstandings between people. So, can a computer programme really reveal lies in people’s email style? There are skeptics, including psychologist, Peter Collett who says “The thing about lying is that a lot of it can be picked up from body language when you talk, it’s got something to do with the timing, the pacing and the actual utterances,” he said. “How can you get software to spot all this? With e-mails you are just left with lexical patterns”.

But with so much communication now carried out by email, maybe we’ve all developed our own styles – our own email idiolects - and the technology can work to reveal our little white lies. Or the big fat ones, like when my children try to get sweets and biscuits out of me by saying that I’m not bald. So, don’t try that one at college…

No comments: