PNAS Nexus

And for years, it was where developers from all over the world shared questions and solutions for free.

A study published in 2024 in the scientific journal PNAS Nexus measured what happened to the site after ChatGPT has launched.

In just six months, activity on Stack Overflow dropped by 25%.

25%.

In their paper, large language models are homogeneously creative.

PNAS Nexus, 2026.

Duke researcher Emily Wenger and Technion cognitive scientist Yoed Kennett tested 22 commercial LLMs against more than 100 humans on standard creativity tasks.

Individual models sometimes outperformed individual people.

OK, this was a very stressful time on multiple levels.

So the paper was published in PNAS Nexus and I was on the job market.

This was, I think, late October 2025. and I was preparing my job talk, which centered on this paper.

When I was looking at a particular plot that was one of the plots to illustrate the trajectory of follower accumulation for both the reposted and the control accounts, I noticed that the error bars were smaller than I thought they should be.

But that actually changed this year.

Two researchers at Wharton ran a very large study, seven separate experiments, north of 10,000 participants, published on the PNAS Nexus back in October.

Ordinary topics, nothing exotic, things like vegetable gardening and spotting a financial scam.

Half the people learned from an AI summary and half the people from ordinary search results.