Nathan Bartley

@nbartley.bsky.social

CS PhD from USC / social networks, games, recommender systems, audits, ⚽️

New preprint with @carlbergstrom.com, Kevin Gross, and @mjcrockett.bsky.social. See Carl's thread. Surprise! Even if LLMs work perfectly, they'll make scientists refine their work less deeply, because they raise the opportunity cost of time, pushing researchers to do more, less well.

A figure describing the results.
Carl T. Bergstrom@carlbergstrom.com · 2w ago

1. We—@eduede.bsky.social, @mjcrockett.bsky.social, Kevin Gross, and I—have a new preprint on the arXiv today, based on ideas that emerged during an @sfiscience.bsky.social workshop in November 2024: The unintended consequences of large language models as a labor-augmenting technology in science.

Hoping Bluesky Communities launches before Musk manages to clean up X, which may take a while given the incentives at work, but maybe not. Even people who remain loyal to Musk know it has become a dumpster fire. It’s a big opportunity, but only if Bluesky provides space for many more communities.

creenshot of an X/Twitter thread in dark mode. Andrej Karpathy writes: “I’ve been on Twitter for almost 2 decades now so I can say with confidence that it has never been this toxic and Reddit-like. I think the alg actively encourages it and people get RL’d by it. Main reason I’ve been coming here less and posting less.” His post shows about 571 replies, 689 reposts, 7.4K likes, and 877K views.

Below it, Elon Musk replies: “We need a complete overhaul of the algorithm.” The reply is timestamped 10:49 PM, 6/24/26, and shows 1.5M views, about 1.9K replies, 1.3K reposts, 10K likes, and 635 bookmarks.
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A few PDSes I haven't seen in awhile broke into the top ten in raw # of active repos (June 2026) 👀 Looking at repos on pds.ls suggests a fair amount of bsky spam. Are there any lists of 'spammy' PDSes (or do devs just roll their own)? I know @mackuba.eu tags some PDSes w/ high bot activity.

A table screenshot showing 6 top independent PDSes by number of active repos, led by brid.gy and eurosky.social

I'd want the opposite of "mute thread" on @bsky.app as a feature: "subscribe to thread" à la slacks "get reply notifications". Really useful when someone asks a good question and I'm interested in seeing the answers.

So I've been digging into bluesky retention data to see what is preventing growth of the ecosystem. Using likes/posts/follows you can see who is active or dormant on ATProto. The headline is that only 5% of users are retained at 28d and 10% of current users churn. That's not pretty

Layer cake of cohorts who joined bsky that are still active -- dominated by Pre Q1 2025 influxRetention metrics showing new users are 5% likely to stay and churn is 10% of current user base (they get resurrected) A break down of growth that shows resurrections / new users / new churn / old churn. It's hovering around steady state
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