twitter topics and why they become popular

NYTimes | AMID the talk last week of a Facebook revolution across the Middle East, Americans and other English speakers took to Twitter — to post about their love lives.

Hashtags — the community-driven shorthand used to identify conversation themes — like “icantdateyou” and “worstpickuplines” were vastly more popular a few days ago than ones like “Egyptians” or “jan25,” a reference to Day 1 of the Egyptian protests. In just one hour last Tuesday, “icantdateyou” racked up nearly 274,000 mentions on Twitter, with posts like “icantdateyou if all you wanna do is fuss” and “icantdateyou if you look like your brother.”

Alas, poor “Mubarak” rated fewer than 11,000 during the same hour. (Many Egyptians could not post on Twitter because their government had temporarily cut off most Internet and cellphone service.)

Sure, many of us are more inclined to toss off frivolous posts than politically charged ones. But a new study of hashtags offers some insight into how and why some topics become popular quickly online while others don’t.

People generally pass on the latest conversational idioms — like “cantlivewithout” or “dontyouhate” — the first few times they see them on Twitter, or they never adopt them at all, according to the study by computer scientists. The researchers analyzed the 500 most popular hashtags among more than three billion messages posted on Twitter from August 2009 to January 2010.

“Idioms are like a sugar rush,” explains Jon Kleinberg, a professor of computer science at Cornell and a co-author of the study. “You see it once, you either use it or you don’t, but the rush wears off.”

More contentious themes like politics take longer to catch on, the researchers found. People tend to wait until they have seen a more polarizing phrase — like “sarahpalin” or “hcr,” short for health care reform — four, five or six times on Twitter before posting it themselves.

We already know that people often influence one another’s behavior. That is the monkey-see-monkey-do premise behind advertising. And it may seem intuitive that different kinds of information spread differently on the Web.

Now, however, researchers at Cornell and a few other universities like Stanford are finding patterns in the way information catches on in cyberspace. Their models could be useful for politicians, social activists, news organizations, marketers, public relations teams and anyone else trying to reach their target audience — or market.

It turns out that the way information spreads online is often more complicated than viral transmission, in which one person passes a link to, say, a YouTube video directly to another person. As with political topics, people often wait until a number of friends or trusted sources have promoted an idea before promulgating it themselves.

The structure of a social network — for example, whether it is made up of close friends and colleagues or of like-minded strangers who follow Lady Gaga — can have more influence than the size of a group, researchers say.