Sometimes a model can be used to find convincing data, for an end run around the "it's just a model" foolishness metasd.com/2025/09/some... #systemdynamics

AI-powered speculators sustain collusive profits without communication or intent, undermining market efficiency and liquidity. Identifying two algorithmic mechanisms and when each arises, from Winston Wei Dou, Itay Goldstein, and Yan Ji https://www.nber.org/papers/w34054

#SystemDynamics graphical conventions for conveyor stocks are flawed metasd.com/2025/07/conv...

Don't worry, the GOP will soon fill the GAO with sycophants who won't say such things.

A bit of history: Barry Richmond on shoehorning the problem into the #systemdynamics archetype: metasd.com/2025/07/shoe...

Catching up on What Is #SystemDynamics? metasd.com/2025/07/what-i

Car-centric infrastructure is a big part of the problem, and it's self-reinforcing. Everyone wants to drive a full-size truck to escape the congestion and noise created by all the full-size trucks.

I think it's hard to solve any housing problem when a tiny fraction of the population holds 50% of the wealth. Here in MT, land availability is not a constraint, but we still have a housing crisis (which the legislature tries and fails to solve with more land availability).

He's right. "Nothing short of devastating"
By @holdenthorp.bsky.social @science.org
www.science.org/doi/10.1126/...

And this may seem like a good rate after BBB inflates the debt and rates go nuts.

Senate Passes Bipartisan Resolution Preventing Themselves From Stopping Trump

Senate Passes Bipartisan Resolution Preventing Themselves From Stopping Trump theonion.com/senate-...

Ah ... that's just what I was asking. So sounds like the issue is ~ that in the update state(t)=state(t-dt)+flux*dt, the flux*dt term ends up contributing 0 due to precision, even though flux*1e6yr would be influential? Apologies if this is in the paper - can't penetrate paywall ATM.

YouTube video by Gene Bellinger Understanding What You Don't Know You Don't Know

www.youtube.com/watch?v=l0Sa...

Does the numerical precision sensitivity also imply noise sensitivity?

A major loss to our understanding of how extreme weather events are affecting us. There are 3 alternative databases I will be using:
Gallagher Re: www.ajg.com/gallagherre/...
Aon: img.clients.aonunited.com/Web/Aon5/%7B...
EM-DAT: www.emdat.be

How climate change is raising your electricity bill a case study of Texas' electricity market

Neat new paper by Andrew Dessler on how climate change is driving up electricity costs in Texas by producing more extreme demand. Details over at The Climate Brink: www.theclimatebrink....

I think this post metasd.com/2024/12/dest... is relevant to practically every bit of news I've seen lately.

I think this post metasd.com/2024/12/dest... is relevant to practically every bit of news I've seen lately.

Silly to think that AI will step in and save us right when the government is at peak stupid.

Tariff dumbnamics in the penguin island autarky - MetaSD The formula behind the recent tariffs has spawned a lot of analysis, presumably because there’s plenty of foolishness to go around. Stand Up Maths has a good one: I want to offer a slightly different ...

The infamous tariff formula as a control system metasd.com/2025/04/tari... #systemdynamics

An video take on policy sensitivity metasd.com/2025/04/comm... #systemdynamics

Sources of Uncertainty - MetaSD The confidence bounds I showed in my previous post have some interesting features. The following plots show three sources of the uncertainty in simulated surveillance for Chronic Wasting Disease in de...

Some cool features from our CWD model metasd.com/2025/04/sour... #systemdynamics

Understanding Prediction - MetaSD I posted my recent blogs on Forrester and forecasting uncertainty over at LinkedIn, and there’s been some good discussion. I want to highlight a few things. First, a colleague pointed out that the way...

This probably should have been "communicating prediction" metasd.com/2025/04/unde...

Forecasting Uncertainty - MetaSD Here’s an example that illustrates what I think Forrester was talking about. This is a set of scenarios from a simple SIR epidemic model in Ventity. There are two sources of uncertainty in this model:...

Catching up on some following posts on forecasting, uncertainty, etc.

metasd.com/2025/03/fore...

Trump’s EPA Plans to Stop Collecting Greenhouse Gas Emissions Data From Most Polluters Climate experts expressed shock and dismay at the move. “It would be a bit like unplugging the equipment that monitors the vital signs of a patient that is critically ill,” one said.

If we unplug a patient’s heart rate monitor, we won’t know if she’s dead. Immortality achieved!

It's kind of amazing how deep the pool of candidates eager to be sycophants and grifters really is.

"Notice and comment is unnecessary because I am ordering the repeal."

For a minute there, the optimists among us thought the courts might provide a bulwark against the United States becoming a "lawless regime".

They still 'need' money, and it's a big, sexy business with no self-motivated customers. The market will only exist if governments create it - which implies sufficient cooperation.

I was proud to write for the New York Times for more than 20 years, but I’m not proud of the newspaper’s buried coverage of the nationwide #handsoff protests. Compare the printed front page today to 1970 Earth Day.