trombonechamp

Joined 9 years ago

Karma
274
Submissions
74
Member since
Nov 17
http://maxshinnpotential.com
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Recent submissions

Comment · 1 month ago
Is there a reason besides performance that maintain_order=False by default? I ask because polars is used in many scientific data analysis pipelines, and non-deterministic behaviour is a well-documented source of bugs in scientific computing (e.g. https://pmc.ncbi.nlm.nih.gov/articles/PMC6919963/). The new default requires users to keep the implementation details of the API in their head while determining whether code is correct or not. This is tricky with scientific computing because the correct answer is not known in advance, so bugs can slide by and silently give incorrect results.
Comment · 2 years ago
Comment · 2 years ago
This is something a bit different, the effect in the paper comes from the eigenvectors of the data matrix. I'm no expert on kernel density estimation, but since it is basically just convolution, I would guess the effect you are describing comes from multiplication in Fourier space.
Comment · 2 years ago
Sorry, I didn't have funding to pay the open access fees. The published version is very similar to the preprint: https://www.biorxiv.org/content/10.1101/2023.06.20.545619v1 Alternatively, if you want the full version, PNAS gave me some eprints to share so just email me (link on my site in my profile) and I will send you a copy!

Not sure what you mean by "things are stable" in this context, could you elaborate?

Comment · 2 years ago
Oh wow, didn't expect to see my paper here. Happy to answer any questions!
Comment · 3 years ago
Comment · 3 years ago
Colemak and Rulemak work nicely together.
Comment · 3 years ago
I would be curious to hear more about your dad's opera.
Comment · 3 years ago
Is this the mattl I think it is? If so, hi!
Comment · 3 years ago
Do people contact you?
Comment · 3 years ago
Comment · 3 years ago
I knew it had to be him when you said Sutton and Barto.

Yeah, I think we just missed each other since your name sounds familiar.

Comment · 3 years ago
Sounds like the classic 4th Floor SHM committee
Comment · 4 years ago
I did my PhD on this topic.

One classic result from biophysics is that, if all of your decisions have a fixed level of difficulty, then what the author suggests is (mathematically) proven to be suboptimal: if a decision feels more difficult, you actually should spend more time on that decision. (Keywords to search for: drift diffusion model[2], sequential probability ratio test[3])

The technical term for what the author is suggesting one should do (not spending so much time on decisions with equal outcomes) is an "urgency signal", or just "urgency" for short. If you are using an urgency signal, then you will spend less time on difficult decisions (i.e. ones with near equal outcomes) than you would without an urgency signal, but still more than you would easy decisions. (For easy decisions, you spend approximately the same amount of time regardless of whether you have an urgency signal.) In the extreme case, for an infinitely strong urgency signal, you will spend equal time on both easy and difficult decisions. (See Paul Cisek's work, e.g., [1].) Conceptually speaking, you need time to detect that the current decision has near-equal outcomes.

It was only recently (mathematically) proven that if you have different levels of difficulty in your decisions, it is optimal to use an urgency signal [4,5]. So since most sequences of decisions aren't all equally difficult (as in the study referenced here), in practice, people will use an urgency signal in decision-making.

Of course, both the desired accuracy and the urgency signal depend on how the decision is being evaluated: if your goal is to make an accurate decision (e.g. buying a house), then you will have a weaker urgency signal and require more evidence before you make a decision. By contrast, if you prioritise decision speed, you will show more urgency signal and require less evidence to make a choice. (The technical term is "speed-accuracy tradeoff".)

Current work suggests that when you are making some decision for the first time, you will not use an urgency signal, but as you become an expert at making those decisions, you will gradually develop an urgency signal [6]. This makes sense conceptually: if you know approximately how hard you can expect these decisions to be, you will recognise the situation where they have approximately the same utility and adjust your strategy accordingly.

[1] https://www.jneurosci.org/content/29/37/11560

[2] https://en.wikipedia.org/wiki/Two-alternative_forced_choice#...

[3] https://en.wikipedia.org/wiki/Sequential_probability_ratio_t...

[4] https://psycnet.apa.org/fulltext/2017-16730-001.pdf

[5] https://link.springer.com/article/10.3758/s13423-017-1340-6

[6] https://www.sciencedirect.com/science/article/abs/pii/S00100...

Comment · 4 years ago
It is definitely not true. One of the many trivial examples is that Betz cells only appear in motor cortex.

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