Scientists have discovered a new method with which people who post false reviews, comments or tweets from social media accounts to espouse opinions can be caught.
Researchers from the University of Texas at San Antonio (UTSA) in the US, describe a statistical method that analyses multiple writing samples - a practice known as 'astroturfing'.
They found that it is challenging for authors to completely conceal their writing style in their text.
Based on word choice, punctuation and context, the method is able to detect whether one person or multiple people are responsible for the samples.
Researchers used writing samples from the most prolific online commenters on various news web sites, and discovered that many people espousing their opinions online were actually all linked to a few singular writers with multiple accounts.
"Astroturfing is legal, but it is questionable ethically. As long as social media has been popular, this has existed," said Kim-Kwang Raymond Choo, associate professor at UTSA.
The practice has been used by businesses to manipulate social media users or online shoppers, by having one paid associate post false reviews on web sites about products for sale.
It is also used on social media wherein astroturferscreate several false accounts to espouse opinions, creating the illusion of a consensus when actually one person is pretending to be many.
"It can be used for any number of reasons. Businesses can use this to encourage support for their products or services, or to sabotage other competing companies by spreading negative opinions through false identities," Choo said.
Candidates for elected office have also been accused of astroturfing to create the illusion of public support for a cause or a campaign.
For example, US President George W Bush, the Tea Party movement, former Secretary of State Hillary Clinton and current Republican presidential candidate Donald Trump have all been accused of astroturfing to claim widespread enthusiasm for their platforms.
Now that Choo has the capability to detect one person pretending to be many online, he is considering further applications for his top-tier research.
Stressing that astroturfing, while frowned upon, is notillegal, he is now looking into whether the algorithm can be used to prevent plagiarism and contract cheating.
"In addition to raising public awareness of the problem,we hope to develop tools to detect astroturfers so that social media users can make informed choices and resist online social manipulation and propaganda," Choo said.