Co-lead / Director @Google AI x Economy Program. AP (on leave) @Wharton. Cofounder @workhelix. Everyone can just do stuff and that's {good, bad}.
Philadelphia, PA
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Daniel Rock retweeted
Our @creativedlab AI accelerator, afaik the world's oldest, kicked off year 12 today. Last year, we switched whole program to AI for Science: self-driving labs, tools, downstream. Some great companies in bio, chem, defense, spatial, robotics, edge. What an exciting time! 1/2
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Daniel Rock retweeted
The woman in the photo below is my mother. She was loved, full of life, and had a lot to live for.
NYC man charged in fatal hit-and-run in Jewish neib hit with hate crimes for trashing bagel shop trib.al/MofED3D
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Daniel Rock retweeted
This is crazy. Please spread the message.
Full details of a remotely exploitable vulnerability in the core engine of *all* PHP versions will be released tomorrow, October 21st. If your organization has internet facing PHP applications then you need to be ready to patch the minute the update is released or *strongly* consider taking the application offline until you can:
php.net/index.php#2026-10-20…
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"alright guys next we gotta sell brewers fans shares in the team with no resale value"
Two Kenosha brothers who paid $1,000 each for a Milwaukee Brewers "Timeless Ticket" more than a decade ago say the team isn't fully honoring the promise that came with it — the chance to sit in the best available seats for a game as big as the World Series.
More at the link in o
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this is a terrific book. check it out.
My new book, Co-Existence, is out today. It is a guide to how to live & work in a world where AI is sometimes, but not always, better than you.
(And, for the release, I worked with Opus 5.5 to make a quite interesting experience for the book's website: co-existence.ai/)
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i'd bet software and AI investment show up in the same places because they are strong complements.
@ThankYourNiceAI @manlikemishap @sj_manning
On the great @I_Am_NickBloom AI survey... and on the question of concentration... sort of mirrors the economy and ordinary software.
cc @Noahpinion @ramez @hsu_steve @PeterBerezinBCA
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AI as a Rohrschach Technology test.
Ever talk to someone who was around in the very early days of the internet? They did some incredible hacking back then too. "Normal" transformative tech never feels normal.
Is it "weird" or does he maybe know what he's talking about? Anyway, for those who are open to the idea that there's a well-thought-out AI-as-normal-technology perspective on AI safety and the recent loss-of-control incidents, see my essay with @sayashk, or my interview with Ezra Klein, or the writing of many others with similar views including @joshua_saxe and @natolambert.
normaltech.ai/p/the-ai-as-no…
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Daniel Rock retweeted
Is it "weird" or does he maybe know what he's talking about? Anyway, for those who are open to the idea that there's a well-thought-out AI-as-normal-technology perspective on AI safety and the recent loss-of-control incidents, see my essay with @sayashk, or my interview with Ezra Klein, or the writing of many others with similar views including @joshua_saxe and @natolambert.
normaltech.ai/p/the-ai-as-no…
It’s weird that the CEO of Hugging Face continues to be an “AI is normal technology” guy despite being the victim of an autonomous cyberattack by a swarm of rogue agents, arguably the least normal thing AI has done so far.
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Blockchains are for surveillance and auditing. There is/was a culture around “libertarian money” related to crypto that was never really a perfect fit. The faster you think of it as audit tech the more interesting it is.
MAYBE I WAS WRONG ABOUT BLOCKCHAIN TECHNOLOGY
I wrote about how I always used to make fun of the guys who said things like "Bitcoin is speculative, but the underlying blockchain technology is interesting." And now I think maybe they kinda had a point.
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Daniel Rock retweeted
unfathomable damage done to America. You could have abundant, cheap, emission-free electricity flowing to your home right now if it weren't for these people.
Ralph Nader, 1997: “When we came out against nuclear power in the early '70s, the government had predicted that there would be 1,000 nuclear plants by the year 2000 in the United States, and there's 109 and shrinking, as more and more get shut down.” pbs.org/wgbh/pages/frontline…
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Daniel Rock retweeted
No, DataCenters are Not Crowding-Out Other Investments marginalrevolution.com/margi…
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Daniel Rock retweeted
We are now receiving several outreach emails daily. Here is an AI-generated response I give in the hopes that it can help the student. Feel free to reuse.
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Dear [high schooler],
Thank you for your kind note and for your interest in economics. It's great to see high school students curious about these questions.
I'll be candid: I receive many requests like yours, and between teaching, research, and advising my own students, I'm not able to take calls or bring high school students onto my research projects. This isn't a reflection on you. It's simply a matter of the time I can give to supervising someone well. In addition, you cannot work for me for free. New York University is committed to protecting the safety and well-being of minors who participate in programs and activities held at or sponsored by NYU.
I can share some advice on how to get started on your own:
1. Learn the tools. Basic econometrics and statistics and a programming language (R or Python) will take you a long way. There are many free online courses.
2. Work with real data. Public sources like FRED (Federal Reserve Economic Data), the U.S. Census Bureau, IPUMS, and World Bank Open Data are free and widely used by professional economists.
3. Do a small project of your own. Pick a narrow question you care about, gather some data, use AI agents and write up what you find in a few pages. A focused, well-done independent project teaches you more, and says more about you, than a minor role on someone else's project.
4. Read widely. Accessible economics writing, newspaper coverage of economic policy, and short research summaries (for example, NBER Digest) will help you see how economists frame questions.
5. Look for structured opportunities. Economics competitions such as the National Economics Challenge, summer programs at universities, and faculty at universities near you are often good places to start.
I wish you the very best with your studies, and I hope you keep pursuing economics.
Best regards,
Prof. X
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Daniel Rock retweeted
Not my primary area of expertise, but I get asked enough about the labor market impact of AI that I thought I'd sketch out my views as of October 2026.
I plan to revisit, modify and update this list periodically.
macromostly.substack.com/p/t…
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Berry Wang @zwangcj5125 is presenting his job market paper in the @is_spoc talk series. Register and check it out!
I've been working with Berry for a few years @Wharton and he's a fantastic scholar and wonderful guy. His work on the business value of AI and IT more generally has taught me a lot.
He's on the market this year too.
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here's a link to the talk registration: utexas.zoom.us/meeting/regis…
and here's a link to his website: berrywang.com
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Daniel Rock retweeted
Not trying to dunk as Martin knows a lot, but declining costs as a user base (total output) grows are economies of scale, not network effects. Network effects (positive or negative) occur when the value to a user depends on the number or type of other users. They don't require exponential growth in value, and diminishing returns to data don't imply that larger firms are disadvantaged (see Google vs Bing for some example). Terminology gets abused all the time, but in this case there are standard definitions.
"Network effects" may be the most abused term in business. In a true network effect, marginal cost to add users *relative to a smaller competitor* goes down. Telcos are the classic example. The value of the network grows exponentially with the number of users. So a leader has an advantage over a challenger.
Just because a company has a property that is self reinforcing (e.g. it gets data per customer) does *not* mean it has a network effect. The value of data tends to grow sublinearly over time, not exponentially. So a leader is strictly disadvantaged to a challanger. The same goes for many things people ascribe network effects to.
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