smartphone screen showing multiple social media apps
Sarah Biren
Sarah Biren
January 20, 2024 ·  5 min read

Posting a lot on social media can make you a jerk, study finds

A new study finds that sharing articles on social media makes people think they know more about the topic than they actually do. For instance, when a person shares a news article, they feel like they are knowledgeable about the subject, even if they had only read the headline and not the article itself. “Sharing can create this rise in confidence because by putting information online, sharers publicly commit to an expert identity,” the study says. “Doing so shapes their sense of self, helping them to feel just as knowledgeable as their post makes them seem.[1]

Sharing articles on social media can make people overconfident 

Marketing professor and co-author of the study Susan M. Broniarczyk explains that people might assume they don’t need to learn more about a certain topic when they feel more knowledgeable about it than they might actually be. “This miscalibrated sense of knowledge can be hard to correct,” she says.

The findings from the study become more apparent alongside data from the Reuters Institute for the Study of Journalism. The 2017 report indicated that when people say they read an online news story, about half of them actually read the whole article, about a quarter read part of it, and about a fifth just read the headline and a few lines. [2]

To prove the theory of people becoming overconfident when sharing news stories, the authors conducted several studies. The first one involved the researchers presenting a series of online news articles to 98 undergraduate students. The headlines included things like “Why Does Theatre Popcorn Cost So Much” and “Red Meats Linked to Cancer.” The students were free to read, share, or do both however they wanted. Then the researchers tested the students’ subjective and objective knowledge from each article, testing what they knew and what they thought they knew. Reading the articles increased subjective and objective knowledge while sharing them increased their sense of subjective knowledge — even when the students only shared the content without reading any of it. 

The second study found that people who shared an article about cancer prevention seemed to believe they knew more about cancer than those who didn’t share it — even if they hadn’t read a word. 

Read: Elon Musk Wonders Whether TikTok Is Destroying Civilization

Overconfidence about knowledge leads to riskier decisions

The next three studies discovered that this phenomenon happens when people internalize the act of sharing information, making it part of their identity, which leads them to think they are as knowledgeable as the articles make them appear to be. In general, posting articles publicly posing as an expert identity makes people think they knew more than they did. The studies compared when participants shared under their own name or an alias, when they shared with friends or strangers, and when they had free choice in what to share.

For the last study, the authors asked 300 active Facebook users to read an article about “How to Start Investing: A Guide for Beginners.” Then they divided the users into a sharing group or no sharing group. They told all of the participants that the content is on several websites and showed them Facebook posts from those websites. However, the researchers told the sharing group to look at all of the articles and choose to share on their own Facebook page. 

In the next phase, the participants undertook what seemed to be an unrelated task. A robo-advisor simulation spoke to them about retirement planning and said placing more money into stocks is “more aggressive” and more money into bonds is “more conservative”. The participants each got a customized investment recommendation and a hypothetical $10,000 to distribute into retirement funds between stocks and bonds. Those in the sharing group were twice as likely to take more risk than what the robo-advisor recommended.

“When people feel they’re more knowledgeable, they’re more likely to make riskier decisions,” said Adrian Ward, assistant professor of marketing, at UT’s McCombs School of Business and co-author of the study. [3]

Read: Facebook’s Own AI Chat Bot Calls Mark Zuckerberg ‘creepy and manipulative’

Overconfidence and sharing fake news on social media

A similar study examined overconfidence in Americans when it comes to new articles. However, this 2021 study examined overconfidence when it comes to spotting fake news. In fact, those who incorrectly think themselves adept at identifying false news can contribute to the news’ circulation. The researchers suggest that overconfidence is one explanation why fast and low-quality information spreads online and on social media. [4]

The study included 8,285 Americans asked to evaluate the accuracy of Facebook headlines then to rate their own accuracy. “No matter what domain, people on average are overconfident… but over 70% of people displaying overconfidence is just such a huge number,” said the lead author, Ben Lyons, an assistant professor of communication at the University of Utah. [5]

The study notes that overconfident people fail to realize when they are wrong, so they are less likely to improve. Other studies found that overconfident people learn the least compared to others in a classroom setting. When it comes to fake news, overconfident people can have an invulnerability bias. Essentially, they don’t think they need many preventative actions, such as being cautious about engaging in questionable websites. Plus, high confidence often comes with less reflection, which makes people less likely to question a dubious news story and more likely to accept false claims.

Stay humble, stay safe

Meanwhile, humble people who are thoughtful, reflective and self-monitoring when online are less likely to fall prey to false information — a good mode to exercise while on social media. “Overconfidence is truly universal. I would be shocked if we didn’t find this in every country we looked at,” said Lyons. “...Although we might not see this extreme level of overconfidence, just based on cultural differences.

Keep Reading: Has Social Media Has Created a Generation of Narcissists?


  1. “I share, therefore I know? Sharing online content – even without reading it – inflates subjective knowledge.” Journal of Consumer Psychology. Adrian F. Ward, Jianqing (Frank) Zheng, Susan M. Broniarczyk.
  2. Digital News Report 2017.” Reuters Institute. Nic Newman, Dr. Richard Fletcher, Dr. Antonis Kalogeropoulos, Dr. David Levy.
  3. “Sharing on Social Media Makes Us Overconfident in Our Knowledge.The University of Texas at Austin.
  4. “Overconfidence in news judgments is associated with false news susceptibility.” PNAS. Benjamin A. Lyons.
  5. “Overconfident of spotting fake news? If so, you may be more likely to fall victim.The Guardian. Natalie Grover. .