A study conducted at Northwestern University determined that celebrities like Ashton Kutcher with millions of Twitter followers are mostly ignored on the social media site, resulting in very little if any influence.

When the researchers applied their mathematical algorithm to the countless tweets that appear on Twitter each day, they found that experts in certain fields were much more likely to cause topics of discussion to become trends. That might come as a relief to social media enthusiasts who crave discussions of substance, and a surprise to critics who argue that social media is prone to inanity.

These findings hit the wire a few months after social media analytics company Sysomos claimed that celebrities' followers don't have any influence, either.

It might all depend on how you crunch the numbers. Don't forget that Justin Bieber used to consistently sit near the top of Twitter's official trends list, and that one source close to Twitter claimed 3% of the network's servers are dedicated to tweets from Bieber and the retweets from his followers. But the Northwestern researchers don't place him very high at all in their own list of trends, which is currently topped by topics related to the Brazilian music awards.

Northwestern professor Alok Choudhary and graduate student Ramanathan Narayanan say that if a celebrity tweets about his or her area of expertise, he or she may actually have some influence in that case — for example, if LeBron James tweets about basketball. But an actor's political statements generally won't hold as much weight as those tweeted by political analysts or politicians.

The researchers set up a website called Pulse of the Tweeters that lists the top trends based on their algorithm, along with the most influential users for each trend. The site is a little ugly, but the data is worth the trip.

[Via Telegraph]