Cameron Martel
@cameronmartel.bsky.social
Assistant Professor at Johns Hopkins Carey Business School.
Studies misinformation & inauthentic behavior online.
Studies misinformation & inauthentic behavior online.
Reposted by Cameron Martel
📣 Yale workshop, Oct 16-17! 📣 How could/should content ranking work? What's new in content moderation? How can platforms promote civility? Hosted by Yale's Institute for Foundations of Data Science (FDS). Great speakers! Submit posters by 9/22! Spread the word! yalefds.swoogo.com/socialalgori...
New Directions in Social Algorithms Research on October 16-17, 2025 at Yale University
As social media algorithms increasingly mediate social experiences, there has been a rapid increase in research on the effects of how these algorithms are configured, alternatives to engagement-centri...
yalefds.swoogo.com
September 12, 2025 at 12:28 PM
📣 Yale workshop, Oct 16-17! 📣 How could/should content ranking work? What's new in content moderation? How can platforms promote civility? Hosted by Yale's Institute for Foundations of Data Science (FDS). Great speakers! Submit posters by 9/22! Spread the word! yalefds.swoogo.com/socialalgori...
Reposted by Cameron Martel
New in TiCS w @dgrand.bsky.social @gordpennycook.bsky.social
It’s been ~10yrs since misinfo research exploded but our paradigms are stuck in the post-2016 “fake news” model
Time for new approaches:
o True/False → Content that misleads
o Belief → Behavior
o Eval interventions in ambiguous settings
It’s been ~10yrs since misinfo research exploded but our paradigms are stuck in the post-2016 “fake news” model
Time for new approaches:
o True/False → Content that misleads
o Belief → Behavior
o Eval interventions in ambiguous settings
August 6, 2025 at 1:40 PM
New in TiCS w @dgrand.bsky.social @gordpennycook.bsky.social
It’s been ~10yrs since misinfo research exploded but our paradigms are stuck in the post-2016 “fake news” model
Time for new approaches:
o True/False → Content that misleads
o Belief → Behavior
o Eval interventions in ambiguous settings
It’s been ~10yrs since misinfo research exploded but our paradigms are stuck in the post-2016 “fake news” model
Time for new approaches:
o True/False → Content that misleads
o Belief → Behavior
o Eval interventions in ambiguous settings
Reposted by Cameron Martel
🚨In PNAS🚨
The right often accuses fact-checkers of political bias
But we analyzed Community Notes on Musk's X and found posts flagged as "misleading" are 2.3x more likely to be written by Reps than Dems!
The issue is Reps sharing misinformation, not fact-checker bias...
www.pnas.org/doi/10.1073/...
The right often accuses fact-checkers of political bias
But we analyzed Community Notes on Musk's X and found posts flagged as "misleading" are 2.3x more likely to be written by Reps than Dems!
The issue is Reps sharing misinformation, not fact-checker bias...
www.pnas.org/doi/10.1073/...
June 17, 2025 at 12:51 PM
🚨In PNAS🚨
The right often accuses fact-checkers of political bias
But we analyzed Community Notes on Musk's X and found posts flagged as "misleading" are 2.3x more likely to be written by Reps than Dems!
The issue is Reps sharing misinformation, not fact-checker bias...
www.pnas.org/doi/10.1073/...
The right often accuses fact-checkers of political bias
But we analyzed Community Notes on Musk's X and found posts flagged as "misleading" are 2.3x more likely to be written by Reps than Dems!
The issue is Reps sharing misinformation, not fact-checker bias...
www.pnas.org/doi/10.1073/...
🚨New in @plosone.org🚨
Corrections of misinfo are often ignored. What can drive engagement?
Twitter field exp & survey followups find
-Social ties matter: users more likely to engage w corrections from accounts who followed user
-Shared partisanship had smaller effects on engagement
shorturl.at/0Ycdp
Corrections of misinfo are often ignored. What can drive engagement?
Twitter field exp & survey followups find
-Social ties matter: users more likely to engage w corrections from accounts who followed user
-Shared partisanship had smaller effects on engagement
shorturl.at/0Ycdp
April 14, 2025 at 2:28 PM
🚨New in @plosone.org🚨
Corrections of misinfo are often ignored. What can drive engagement?
Twitter field exp & survey followups find
-Social ties matter: users more likely to engage w corrections from accounts who followed user
-Shared partisanship had smaller effects on engagement
shorturl.at/0Ycdp
Corrections of misinfo are often ignored. What can drive engagement?
Twitter field exp & survey followups find
-Social ties matter: users more likely to engage w corrections from accounts who followed user
-Shared partisanship had smaller effects on engagement
shorturl.at/0Ycdp
Reposted by Cameron Martel
In the latest episode of the OII podcast, we're tackling misinformation and polarization on social media. What's the real-world impact? How are governments responding? And what about AI and deepfakes?
Listen here: podcasts.ox.ac.uk/why-social-m...
Listen here: podcasts.ox.ac.uk/why-social-m...
Why social media is the new frontier for misinformation, and what we can do about it: Professor Mohsen Mosleh and Cameron Martel
In the sixth episode of the OII Podcast, our experts discuss topics such as: * The real world impacts that arise when people increasingly identify with their political tribes online * What role govern...
podcasts.ox.ac.uk
March 13, 2025 at 1:28 PM
In the latest episode of the OII podcast, we're tackling misinformation and polarization on social media. What's the real-world impact? How are governments responding? And what about AI and deepfakes?
Listen here: podcasts.ox.ac.uk/why-social-m...
Listen here: podcasts.ox.ac.uk/why-social-m...
Reposted by Cameron Martel
Nice blog post by @cameronmartel.bsky.social on our NHB paper showing fact-checker warnings work even for people who distrust fact-checkers. Particularly relevant re Meta's rollback of fact checking based (among other things) on claim that fact-checkers lost publics trust spsp.org/news/charact...
Fact-checker Warnings Are Surprisingly Effective Even For Skeptics | SPSP
Even when people distrust fact-checkers, they’re still influenced by warning labels on false news.
spsp.org
March 6, 2025 at 9:06 PM
Nice blog post by @cameronmartel.bsky.social on our NHB paper showing fact-checker warnings work even for people who distrust fact-checkers. Particularly relevant re Meta's rollback of fact checking based (among other things) on claim that fact-checkers lost publics trust spsp.org/news/charact...
Reposted by Cameron Martel
New WP!
The illusory truth effect (repetition -> belief) is core to psych of beliefs, & thought to be a deep bias impacting misinfo, persuasion & advertising
Why would cognition include such a flaw? We argue it is a rational adaptation to high-quality info environments 🧵1/
The illusory truth effect (repetition -> belief) is core to psych of beliefs, & thought to be a deep bias impacting misinfo, persuasion & advertising
Why would cognition include such a flaw? We argue it is a rational adaptation to high-quality info environments 🧵1/
February 1, 2025 at 10:50 PM
New WP!
The illusory truth effect (repetition -> belief) is core to psych of beliefs, & thought to be a deep bias impacting misinfo, persuasion & advertising
Why would cognition include such a flaw? We argue it is a rational adaptation to high-quality info environments 🧵1/
The illusory truth effect (repetition -> belief) is core to psych of beliefs, & thought to be a deep bias impacting misinfo, persuasion & advertising
Why would cognition include such a flaw? We argue it is a rational adaptation to high-quality info environments 🧵1/
Reposted by Cameron Martel
🚨New WP🚨
Remember Musk+Zuck+Trump+Jordan etc crying fact-checker bias b/c Reps were flagged more than Dems? We analyzed Community Notes on Musk's X and guess what: posts flagged as "misleading" are 67% more likely to be written by Reps! The issue is Reps, not fact-checkers...
osf.io/preprints/ps...
Remember Musk+Zuck+Trump+Jordan etc crying fact-checker bias b/c Reps were flagged more than Dems? We analyzed Community Notes on Musk's X and guess what: posts flagged as "misleading" are 67% more likely to be written by Reps! The issue is Reps, not fact-checkers...
osf.io/preprints/ps...
January 31, 2025 at 2:54 PM
🚨New WP🚨
Remember Musk+Zuck+Trump+Jordan etc crying fact-checker bias b/c Reps were flagged more than Dems? We analyzed Community Notes on Musk's X and guess what: posts flagged as "misleading" are 67% more likely to be written by Reps! The issue is Reps, not fact-checkers...
osf.io/preprints/ps...
Remember Musk+Zuck+Trump+Jordan etc crying fact-checker bias b/c Reps were flagged more than Dems? We analyzed Community Notes on Musk's X and guess what: posts flagged as "misleading" are 67% more likely to be written by Reps! The issue is Reps, not fact-checkers...
osf.io/preprints/ps...
Reposted by Cameron Martel
Three new articles discuss Meta’s decision to drop fact-checkers and shift to a "Community Notes" model, sparking concerns about misinformation.
What's at stake? Here are three smart takes from experts.
A short thread: 🧵
What's at stake? Here are three smart takes from experts.
A short thread: 🧵
January 29, 2025 at 9:39 PM
Three new articles discuss Meta’s decision to drop fact-checkers and shift to a "Community Notes" model, sparking concerns about misinformation.
What's at stake? Here are three smart takes from experts.
A short thread: 🧵
What's at stake? Here are three smart takes from experts.
A short thread: 🧵
Reposted by Cameron Martel
🚨OpEd+data: Meta is out of step with public opinion🚨
Zuck cut moderation b/c he said people no longer want it. But he's wrong!
We polled 1k Americans and most people, including majority of Reps:
i) want content moderation
ii) don't want Community Notes w/o fact-checkers
thehill.com/opinion/tech...
Zuck cut moderation b/c he said people no longer want it. But he's wrong!
We polled 1k Americans and most people, including majority of Reps:
i) want content moderation
ii) don't want Community Notes w/o fact-checkers
thehill.com/opinion/tech...
January 28, 2025 at 7:44 PM
🚨OpEd+data: Meta is out of step with public opinion🚨
Zuck cut moderation b/c he said people no longer want it. But he's wrong!
We polled 1k Americans and most people, including majority of Reps:
i) want content moderation
ii) don't want Community Notes w/o fact-checkers
thehill.com/opinion/tech...
Zuck cut moderation b/c he said people no longer want it. But he's wrong!
We polled 1k Americans and most people, including majority of Reps:
i) want content moderation
ii) don't want Community Notes w/o fact-checkers
thehill.com/opinion/tech...
Reposted by Cameron Martel
🚨New WP🚨
We examine news sharing on 7 platforms:
1)Right-leaning platforms=lower quality news
2)Echo-platforms: Right-leaning news gets more engagement on right-leaning platforms, vice-versa for left-leaning
3)But low-quality news gets more engagement EVERYWHERE, even BlueSky!
osf.io/preprints/ps...
We examine news sharing on 7 platforms:
1)Right-leaning platforms=lower quality news
2)Echo-platforms: Right-leaning news gets more engagement on right-leaning platforms, vice-versa for left-leaning
3)But low-quality news gets more engagement EVERYWHERE, even BlueSky!
osf.io/preprints/ps...
December 9, 2024 at 7:48 PM
🚨New WP🚨
We examine news sharing on 7 platforms:
1)Right-leaning platforms=lower quality news
2)Echo-platforms: Right-leaning news gets more engagement on right-leaning platforms, vice-versa for left-leaning
3)But low-quality news gets more engagement EVERYWHERE, even BlueSky!
osf.io/preprints/ps...
We examine news sharing on 7 platforms:
1)Right-leaning platforms=lower quality news
2)Echo-platforms: Right-leaning news gets more engagement on right-leaning platforms, vice-versa for left-leaning
3)But low-quality news gets more engagement EVERYWHERE, even BlueSky!
osf.io/preprints/ps...
🚨New in JEP:G🚨
Why do ppl preferentially reciprocate follows by co-partisans online? In a Twitter field exp & online survey exp we find:
-Both content *and* social prefs drive co-party tie-making
-Distinct roles for in-party pref & out-party dispref
dx.doi.org/10.1037/xge0...
Why do ppl preferentially reciprocate follows by co-partisans online? In a Twitter field exp & online survey exp we find:
-Both content *and* social prefs drive co-party tie-making
-Distinct roles for in-party pref & out-party dispref
dx.doi.org/10.1037/xge0...
October 16, 2024 at 4:16 PM
🚨New in JEP:G🚨
Why do ppl preferentially reciprocate follows by co-partisans online? In a Twitter field exp & online survey exp we find:
-Both content *and* social prefs drive co-party tie-making
-Distinct roles for in-party pref & out-party dispref
dx.doi.org/10.1037/xge0...
Why do ppl preferentially reciprocate follows by co-partisans online? In a Twitter field exp & online survey exp we find:
-Both content *and* social prefs drive co-party tie-making
-Distinct roles for in-party pref & out-party dispref
dx.doi.org/10.1037/xge0...
Reposted by Cameron Martel
🚨Out in Nature!🚨
Many (eg Trump JimJordan Musk Vance) have accused social media of anti-conservative bias - but is this accurate?
We test empirically, and it's more complicated than you might think: conservatives ARE suspended more, but also share more misinfo
www.nature.com/articles/s41...
Many (eg Trump JimJordan Musk Vance) have accused social media of anti-conservative bias - but is this accurate?
We test empirically, and it's more complicated than you might think: conservatives ARE suspended more, but also share more misinfo
www.nature.com/articles/s41...
October 2, 2024 at 5:03 PM
🚨Out in Nature!🚨
Many (eg Trump JimJordan Musk Vance) have accused social media of anti-conservative bias - but is this accurate?
We test empirically, and it's more complicated than you might think: conservatives ARE suspended more, but also share more misinfo
www.nature.com/articles/s41...
Many (eg Trump JimJordan Musk Vance) have accused social media of anti-conservative bias - but is this accurate?
We test empirically, and it's more complicated than you might think: conservatives ARE suspended more, but also share more misinfo
www.nature.com/articles/s41...
Reposted by Cameron Martel
In a new article in Political Communication, @mattgraham.bsky.social and I study how to increase readership of fact-checks. It's hard! Social pressure, civic duty and small payments help; leveraging Party ID doesn't.
www.tandfonline.com/doi/full/10....
Ungated: osf.io/preprints/os...
www.tandfonline.com/doi/full/10....
Ungated: osf.io/preprints/os...
September 19, 2024 at 8:13 PM
In a new article in Political Communication, @mattgraham.bsky.social and I study how to increase readership of fact-checks. It's hard! Social pressure, civic duty and small payments help; leveraging Party ID doesn't.
www.tandfonline.com/doi/full/10....
Ungated: osf.io/preprints/os...
www.tandfonline.com/doi/full/10....
Ungated: osf.io/preprints/os...
And here is a Research Briefing summary of our work in Nature Human Behaviour from myself & @dgrand.bsky.social :
rdcu.be/dT3dq
rdcu.be/dT3dq
September 18, 2024 at 2:47 PM
And here is a Research Briefing summary of our work in Nature Human Behaviour from myself & @dgrand.bsky.social :
rdcu.be/dT3dq
rdcu.be/dT3dq
Reposted by Cameron Martel
🚨Out in Science!🚨
Conspiracy beliefs famously resist correction, ya?
WRONG: We show brief convos w GPT4 reduce conspiracy beliefs by ~20%!
-Lasts over 2mo
-Works on entrenched beliefs
-Tailored AI response rebuts specific evidence offered by believers
www.science.org/doi/10.1126/...
Conspiracy beliefs famously resist correction, ya?
WRONG: We show brief convos w GPT4 reduce conspiracy beliefs by ~20%!
-Lasts over 2mo
-Works on entrenched beliefs
-Tailored AI response rebuts specific evidence offered by believers
www.science.org/doi/10.1126/...
September 12, 2024 at 6:02 PM
🚨Out in Science!🚨
Conspiracy beliefs famously resist correction, ya?
WRONG: We show brief convos w GPT4 reduce conspiracy beliefs by ~20%!
-Lasts over 2mo
-Works on entrenched beliefs
-Tailored AI response rebuts specific evidence offered by believers
www.science.org/doi/10.1126/...
Conspiracy beliefs famously resist correction, ya?
WRONG: We show brief convos w GPT4 reduce conspiracy beliefs by ~20%!
-Lasts over 2mo
-Works on entrenched beliefs
-Tailored AI response rebuts specific evidence offered by believers
www.science.org/doi/10.1126/...
Reposted by Cameron Martel
Ungated link sites.dartmouth.edu/nyhan/files/...
New 🚨 The Narrow Reach of Targeted Corrections: No Impact on Broader Beliefs About Election Integrity 🚨 link.springer.com/article/10.1...
The dangers of fact-check Whac-A-Mole: debunking false claims about the 2022 AZ election reduced misperceptions but did not improve overall election confidence
The dangers of fact-check Whac-A-Mole: debunking false claims about the 2022 AZ election reduced misperceptions but did not improve overall election confidence
September 5, 2024 at 3:23 PM
Ungated link sites.dartmouth.edu/nyhan/files/...
🚨New in Nature Human Behaviour🚨
Will misinfo warning labels backfire for ppl who distrust fact-checkers? No!
Labels reduce belief in & sharing of false news even for those highly distrusting of fact-checkers - warning labels are a key tool for platforms!
rdcu.be/dSHtF
Will misinfo warning labels backfire for ppl who distrust fact-checkers? No!
Labels reduce belief in & sharing of false news even for those highly distrusting of fact-checkers - warning labels are a key tool for platforms!
rdcu.be/dSHtF
September 5, 2024 at 5:01 PM
🚨New in Nature Human Behaviour🚨
Will misinfo warning labels backfire for ppl who distrust fact-checkers? No!
Labels reduce belief in & sharing of false news even for those highly distrusting of fact-checkers - warning labels are a key tool for platforms!
rdcu.be/dSHtF
Will misinfo warning labels backfire for ppl who distrust fact-checkers? No!
Labels reduce belief in & sharing of false news even for those highly distrusting of fact-checkers - warning labels are a key tool for platforms!
rdcu.be/dSHtF
Reposted by Cameron Martel
Harnessing the wisdom of high-quality online crowds could help scale up efforts to identify and intervene on
#misinformation, @cameronmartel.bsky.social said.
#misinformation, @cameronmartel.bsky.social said.
Crowding Out Falsehoods
Psychological scientists are harnessing the biases and expertise of imperfect individuals to enhance the wisdom of crowds.
www.psychologicalscience.org
July 16, 2024 at 12:29 PM
Harnessing the wisdom of high-quality online crowds could help scale up efforts to identify and intervene on
#misinformation, @cameronmartel.bsky.social said.
#misinformation, @cameronmartel.bsky.social said.
Reposted by Cameron Martel
📢POSTDOC OPPORTUNITY📢
Come join me Gord Pennycook and @tomcostello.bsky.social
as we launch a research program using dialogues with LLMs as a tool to study human psychology and decision-making! Located at MIT or Cornell, and open applicants from all kinds of intellectual backgrounds/training!
Come join me Gord Pennycook and @tomcostello.bsky.social
as we launch a research program using dialogues with LLMs as a tool to study human psychology and decision-making! Located at MIT or Cornell, and open applicants from all kinds of intellectual backgrounds/training!
June 25, 2024 at 4:23 PM
📢POSTDOC OPPORTUNITY📢
Come join me Gord Pennycook and @tomcostello.bsky.social
as we launch a research program using dialogues with LLMs as a tool to study human psychology and decision-making! Located at MIT or Cornell, and open applicants from all kinds of intellectual backgrounds/training!
Come join me Gord Pennycook and @tomcostello.bsky.social
as we launch a research program using dialogues with LLMs as a tool to study human psychology and decision-making! Located at MIT or Cornell, and open applicants from all kinds of intellectual backgrounds/training!
Reposted by Cameron Martel
Partisans blocking counter-partisans drives polarization on Twitter, with Dems more likely to block Reps than vice versa because Dems want to block accounts that post low-quality information, finds @cameronmartel.bsky.social @mmosleh.bsky.social @dgrand.bsky.social et al. doi.org/10.1093/pnas...
June 3, 2024 at 4:40 PM
Partisans blocking counter-partisans drives polarization on Twitter, with Dems more likely to block Reps than vice versa because Dems want to block accounts that post low-quality information, finds @cameronmartel.bsky.social @mmosleh.bsky.social @dgrand.bsky.social et al. doi.org/10.1093/pnas...
Reposted by Cameron Martel
Prior work on political assortment on social networks mostly focus on "connect" to like-minded others. In our recent work, we showed "disconnect" (blocking) is also a key driver of polarized social networks. h/t @cameronmartel.bsky.social @dgrand.bsky.social Tauhid Zaman Qi yang #socialmedia
🚨New in PNAS Nexus🚨
Twitter field exps:
-Users block counter-partisans 12x more than co-partisans
-Dems block Reps more than vice-versa
Survey exps:
-Why block? To not see blocked user's posts
-Dem/Rep diff prob bc Dems block misinfo/toxic sharers more
academic.oup.com/pnasnexus/ar...
Twitter field exps:
-Users block counter-partisans 12x more than co-partisans
-Dems block Reps more than vice-versa
Survey exps:
-Why block? To not see blocked user's posts
-Dem/Rep diff prob bc Dems block misinfo/toxic sharers more
academic.oup.com/pnasnexus/ar...
May 29, 2024 at 9:36 AM
Prior work on political assortment on social networks mostly focus on "connect" to like-minded others. In our recent work, we showed "disconnect" (blocking) is also a key driver of polarized social networks. h/t @cameronmartel.bsky.social @dgrand.bsky.social Tauhid Zaman Qi yang #socialmedia
🚨New in PNAS Nexus🚨
Twitter field exps:
-Users block counter-partisans 12x more than co-partisans
-Dems block Reps more than vice-versa
Survey exps:
-Why block? To not see blocked user's posts
-Dem/Rep diff prob bc Dems block misinfo/toxic sharers more
academic.oup.com/pnasnexus/ar...
Twitter field exps:
-Users block counter-partisans 12x more than co-partisans
-Dems block Reps more than vice-versa
Survey exps:
-Why block? To not see blocked user's posts
-Dem/Rep diff prob bc Dems block misinfo/toxic sharers more
academic.oup.com/pnasnexus/ar...
May 28, 2024 at 8:29 PM
🚨New in PNAS Nexus🚨
Twitter field exps:
-Users block counter-partisans 12x more than co-partisans
-Dems block Reps more than vice-versa
Survey exps:
-Why block? To not see blocked user's posts
-Dem/Rep diff prob bc Dems block misinfo/toxic sharers more
academic.oup.com/pnasnexus/ar...
Twitter field exps:
-Users block counter-partisans 12x more than co-partisans
-Dems block Reps more than vice-versa
Survey exps:
-Why block? To not see blocked user's posts
-Dem/Rep diff prob bc Dems block misinfo/toxic sharers more
academic.oup.com/pnasnexus/ar...
🚨New review🚨 Do warning labels on misinformation actually work?
In Current Opinion in Psychology, @dgrand.bsky.social & I show that the answer is YES: warnings can reduce belief & sharing by ~25-50%!
We also review moderators (eg more visible=bigger effect)
www.sciencedirect.com/science/arti...
In Current Opinion in Psychology, @dgrand.bsky.social & I show that the answer is YES: warnings can reduce belief & sharing by ~25-50%!
We also review moderators (eg more visible=bigger effect)
www.sciencedirect.com/science/arti...
April 24, 2024 at 9:38 PM
🚨New review🚨 Do warning labels on misinformation actually work?
In Current Opinion in Psychology, @dgrand.bsky.social & I show that the answer is YES: warnings can reduce belief & sharing by ~25-50%!
We also review moderators (eg more visible=bigger effect)
www.sciencedirect.com/science/arti...
In Current Opinion in Psychology, @dgrand.bsky.social & I show that the answer is YES: warnings can reduce belief & sharing by ~25-50%!
We also review moderators (eg more visible=bigger effect)
www.sciencedirect.com/science/arti...
🚨Out in Psych Sci🚨
Prompting accuracy can increase news sharing quality - but is this true for those on the political right?
In an ADVERSARIAL COLLABORATION we find:
➡️ Acc prompts increase sharing quality of Republicans
➡️ Some evidence of greater efficacy for those on left v right
Prompting accuracy can increase news sharing quality - but is this true for those on the political right?
In an ADVERSARIAL COLLABORATION we find:
➡️ Acc prompts increase sharing quality of Republicans
➡️ Some evidence of greater efficacy for those on left v right
March 29, 2024 at 9:08 PM
🚨Out in Psych Sci🚨
Prompting accuracy can increase news sharing quality - but is this true for those on the political right?
In an ADVERSARIAL COLLABORATION we find:
➡️ Acc prompts increase sharing quality of Republicans
➡️ Some evidence of greater efficacy for those on left v right
Prompting accuracy can increase news sharing quality - but is this true for those on the political right?
In an ADVERSARIAL COLLABORATION we find:
➡️ Acc prompts increase sharing quality of Republicans
➡️ Some evidence of greater efficacy for those on left v right