Super-Nice People May Be More Likely to Betray You


When it comes to people, it’s the sickly-sweet ones you have to watch out for. That’s the conclusion of a study by a team of linguists and computer scientists, who analyzed the conversational patterns of people playing an online strategy game.

As writer Rachel Ehrenberg explains in Science News, interpersonal conflicts like betrayal can be very difficult to study. It’s not as if you can bring two people into the lab, instruct one to backstab the other, and draw reasonable conclusions from their behavior while they’re being watched. “We all know betrayal exists,” computer scientist Cristian Danescu-Niculescu-Mizil told Ehrenberg. “But finding relevant data is really hard.”

So when Danescu-Niculescu-Mizil heard about the game Diplomacy, a lightbulb went off in his head. In this strategy game, which was invented during the Cold War, players compete to gain territories not with weapons or armies, but with words. The game has maintained a dedicated fanbase for more than half a century. Today, most games of Diplomacy are played online, with players conducting their negotiations, alliances, treaties, manipulations, coups, and, of course, betrayal from behind their keyboards. 

Danescu-Niculescu-Mizil realized that the transcripts of these conversations could be a data goldmine. He joined forces with fellow computer scientist (and diehard Diplomacy fan) Jordan Boyd-Graber, as well as computational linguist Vlad Niculae and data mining expert Srijan Kumar. The researchers compiled 145,000 messages between players and analyzed them in the hopes of finding what they called “linguistic harbingers of betrayal.” 

They found them, all right. “Sudden changes in the balance of certain conversational attributes—such as positive sentiment, politeness, or focus on future planning—signal impending betrayal,” they wrote in a report. In other words, if somebody starts being really, really polite or eager all of a sudden, it might be time to start edging away. 

An example, taken from a game transcript:

GERMANY: Can I suggest you move your armies east and then I will support you? Then next year you move [there] and dismantle Turkey. I will deal with England and France, you take out Italy.  AUSTRIA: Sounds like a perfect plan! Happy to follow through. And—thank you Bruder!

“Immediately after this exchange,” the researchers noted, “Austria invaded German territory.”

It is important to keep in mind this study is only looking at players in a betrayal-centric game. It’s possible that the really super-friendly person in your office is legitimately super-friendly and not out to get you. We’ll have to wait on more research to find out for sure.

Danescu-Niculescu-Mizil and his colleagues presented their findings last summer at the Annual Meeting of the Society for Computational Linguistics. The acknowledgments section of their report [PDF] was both topical and pointed: “This work is dedicated to all those who betrayed us.”