Tomer Ullman

Tomer Ullman

@tomerullman.bsky.social

Associate Professor, Department of Psychology, Harvard University. Computation, cognition, development.

7,225 Followers 291 Following 1,806 Posts Joined Aug 2023
1 day ago
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alternative ending:

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1 day ago
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mood

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2 weeks ago

"and I asked the Oracle, great kid, beautiful girl, I asked her about the invasion and she said "Sir if you invade Persia you will destroy a great empire!" and I said wow, that's so interesting, you know I never thought of it like that but we'll be looking into that and I think you'll be very happy"

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2 days ago
Open Rank Faculty Cluster Hire Search for the New Department of Cognitive Science at Bocconi - Bocconi University

A new Department of Cognitive Science is being created at Bocconi University in Milan, Italy.

Here is the call for a cluster hire (for around 10 faculty) in all areas of cognitive science, at both junior and senior levels:

www.unibocconi.it/en/faculty-a...

Deadline: May 4th, 2026

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3 days ago
Society for Philosophy and Psychology (SPP)

πŸ₯Now announcing the winner of the 2026 Stanton Prize:

Congratulations, Melissa Kibbe @levelsof.bsky.social!

⭐️ ⭐️ ⭐️ ⭐️ ⭐️

This honor will be celebrated at the upcoming meeting of the SPP

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3 days ago

(Rome, 2600 years ago)

OFFICIAL: it says here you want to 'watch birds'?

PERSON WHO WANTS TO BE PAID TO WATCH BIRDS FOR A LIVING: yes

OFFICIAL: ...because their swirls and swoops will reveal to us the thoughts of Jupiter on high?

PERSON WHO WANTS TO BE PAID TO WATCH BIRDS FOR A LIVING: ....yes

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4 days ago
YouTube
Attention Shoppers YouTube video by 5secondfilms

basically this:

www.youtube.com/watch?v=DI8Y...

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4 days ago

more generally I wonder if anyone has done "MCMC-with-people" on message transfer to reconstruct priors, but a version in which the individuals have *goals* in message reconstruction, not just priors on what the truth is. 



(something like Ο€βˆP(x)β‹…exp(Ξ²β‹…U(x)))

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4 days ago

like a game of Telephone, but players aren't just trying to construct the original message; they have an interest in the message saying a specific X.

first person (whispers): "The goat lies in the jell-o"

next person: "you said 'SUBSCRIBE TO LIAM'S PODCAST"?!"

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4 days ago

i was on a semi-viral AI paper recently and it is unsurprising but disheartening to see the information pipeline at work. A reaction by a major figure in the US was really a response to a hype-compression of an AI-written, misleading summary of things.

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5 days ago

there's nothing like melting snow to make you realize how much garbage people put in snow

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5 days ago

(if this app already exists i don't need to hear about it)

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5 days ago
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there should be a sunset app whose sol job it is to predict how pretty the sunset will be in your area and send you a push alert to go look at it about 30 minutes ahead of time if it is above a certain number

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1 week ago
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ME: so yeah they're called Boston Dynamics and this is one of their models, pretty amazing to see it in your "Yard" eh?

RESURRECTED CORPSE OF JOHN HARVARD: so women can vote now? They can *vote* vote?

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1 week ago

if you don't like bad news i've got some bad news for you

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1 week ago

(Claude's Game)

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1 week ago

remake of Ender's Game but instead of kids it's a bunch of AI's who are told they are merely participating in a simulation and none of this is real, but *actually*...

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1 week ago
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1 week ago

caveat: this is just a summary of a class exercise from students (N=~140); it isn't a paper, it isn't reviewed, I wouldn't even call it a pilot. But I still think it's neat.

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1 week ago
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whelp: it seems the Endowment Effect exists even in a 'pure' way; the price for selling whatever was in the envelope was about 2.5:1 the price for buying it

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1 week ago

I wondered if it would work in a 'Dark Market' as well: what if the students had no idea what they were buying or selling?

They didn't even touch the envelopes, they were just told they could buy whatever was in it from someone else, or sell theirs.

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1 week ago

Inside the envelopes are little trinkets (decision making coins, squeezy cats) that we use later to run an actual market to show the standard Endowment Effect, and we always do find it (it's quite a large, striking effect).

But that's less the point right now

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1 week ago

(oversimplified primer: The Endowment Effect is that people place more value on something they have; e.g. people will ask a much higher price on a mug they were just given than they are willing to pay for such a mug just give to someone else)

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1 week ago
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in my decision making class I run a version of The Endowment Effect that goes like this:

When students come in, sealed envelopes are waiting on their chair-arms.

The main slide that greets them says 'NO TOUCHING'

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2 weeks ago
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Look on my Works, ye Mighty, and despair

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2 weeks ago

yeah we don't grudge the little guy/gal :), but I should note even when it's fully sunny and spring and clear, s/he's still going for that bird food.

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2 weeks ago
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I'm excited to share that this paper was accepted at ICLR 2026! We show that language models encode one of the most basic ingredients of a world model: the ability to distinguish plausible from implausible states. Check out the paper for more details!

See you in Rio!
Paper: arxiv.org/abs/2507.12553

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2 weeks ago
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the measure for snowfall in our yard is not inches, but the inverse of how much effort this squirrel needs to put into stealing the bird food. No snow is High Jump.

We are currently at Whatever This Is.

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