Niko Jaakkola
@nikoecon.bsky.social
Associate Prof, Uni Bologna, Economics of climate & natural resources. Tweeting also as citizen, 🇫🇮/🇪🇺 and as resident 🇮🇹. Views are mine, most likely borrowed from somewhere.
Suomeksi @nikoekon.bsky.social
https://sites.google.com/view/jaakkola
Suomeksi @nikoekon.bsky.social
https://sites.google.com/view/jaakkola
I.e., if you say "this is too complicated to think about using a model, you should do X because that leads to Y" -- you're also using a model there -- and that model is s black box, because it's hard to know what assumptions have led you to your conclusion.
November 2, 2025 at 2:21 PM
I.e., if you say "this is too complicated to think about using a model, you should do X because that leads to Y" -- you're also using a model there -- and that model is s black box, because it's hard to know what assumptions have led you to your conclusion.
That's because the world is complicated and we need to simplify drastically to be able to solve a mathematical model. Whether the simplifications make the model "too simple" depends on the phenomenon and question at hand. But that also holds for your preferred casual English-language model!
November 2, 2025 at 2:21 PM
That's because the world is complicated and we need to simplify drastically to be able to solve a mathematical model. Whether the simplifications make the model "too simple" depends on the phenomenon and question at hand. But that also holds for your preferred casual English-language model!
Of course models are simplifications, and they may be wrong. Decisionmakers should absolutely keep this in mind when interpreting predictions based on explicit, mathematical models: most things are not included, and some may be important.
November 2, 2025 at 2:21 PM
Of course models are simplifications, and they may be wrong. Decisionmakers should absolutely keep this in mind when interpreting predictions based on explicit, mathematical models: most things are not included, and some may be important.
Economists often write down explicit models which typically make numerical predictions of observable quantities in the world. The nice thing about this is that it makes it very clear what assumptions go into the model, and that the predictions can be tested against data.
November 2, 2025 at 2:21 PM
Economists often write down explicit models which typically make numerical predictions of observable quantities in the world. The nice thing about this is that it makes it very clear what assumptions go into the model, and that the predictions can be tested against data.
Like, predicting that gravity will not disappear 5 seconds from now is a prediction from a casual model of physics we all have in our heads. Or "the prime minister should not flatter Trump, he's going to be unreliable anyway" is a prediction based on a model of Trump.
November 2, 2025 at 2:21 PM
Like, predicting that gravity will not disappear 5 seconds from now is a prediction from a casual model of physics we all have in our heads. Or "the prime minister should not flatter Trump, he's going to be unreliable anyway" is a prediction based on a model of Trump.
We Europeans are all in the same boat. We've got the institutions already, to do this together -- the EU, and NATO. Given Russia’s regrettable, criminal, imperialist, downright evil behaviour, funding Ukraine in its struggle is a cheap way to stop Putin.
October 31, 2025 at 11:47 AM
We Europeans are all in the same boat. We've got the institutions already, to do this together -- the EU, and NATO. Given Russia’s regrettable, criminal, imperialist, downright evil behaviour, funding Ukraine in its struggle is a cheap way to stop Putin.
The only issue is that, for Europe, Ukraine provides a public good by fighting Russia. So all countries would like someone else to finance it. But at least it's a *European* public good -- not global, like a stable climate is (which makes climate change a very wicked problem).
October 31, 2025 at 11:47 AM
The only issue is that, for Europe, Ukraine provides a public good by fighting Russia. So all countries would like someone else to finance it. But at least it's a *European* public good -- not global, like a stable climate is (which makes climate change a very wicked problem).
Many things to highlight but let me go with this. Ukraine's financing needs are actually not that much as a share of EU/NATO GDP (even assuming US is not participating). And the costs of deterrence failing are potentially VERY high. It's a no-brainer.
October 31, 2025 at 11:47 AM
Many things to highlight but let me go with this. Ukraine's financing needs are actually not that much as a share of EU/NATO GDP (even assuming US is not participating). And the costs of deterrence failing are potentially VERY high. It's a no-brainer.