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| bio | website | linkedin.com/in/crntaylor |
|---|---|---|
| location | London, United Kingdom | |
| age | 29 | |
| visits | member for | 2 years, 5 months |
| seen | 23 mins ago | |
| stats | profile views | 2,476 |
I'm interested in functional programming, type theory and very applied math - including systematic trading, statistics, artificial intelligence and machine learning.
I'm working on an AI Library in Haskell. Feel free to fork.
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May 11 |
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How often does it happen that the oldest person alive dies? Thanks for this gwern. Love your site, by the way! |
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May 10 |
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How often does it happen that the oldest person alive dies? @GarethMcCaughan Nice spot! That changes the rate to 1 in every 1.08 years. And now you mention it, I'm not testing for the possibility that the event "the oldest person alive dies" happens more than once every year... |
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May 10 |
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How often does it happen that the oldest person alive dies? @gugg I deleted it to keep the answer simple, I could regenerate it and include it again. |
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May 10 |
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How often does it happen that the oldest person alive dies? @GarethMcCaughan My code is in a gist here: gist.github.com/chris-taylor/5554669 |
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May 10 |
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How often does it happen that the oldest person alive dies? @GarethMcCaughan It's possible! I'll put the code in a gist so you can check it (unfortunately you won't be able to run it as it uses some of my proprietary library of utilities... but you can at least check it for errors manually). |
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May 10 |
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How often does it happen that the oldest person alive dies? I fitted a power law to the mortality rate and extrapolated it. It appears to underestimate the acceleration of the mortality rate between 60 and 100 somewhat. However, an exponential fit (which is what I tried first) significantly overestimates the acceleration of the mortality rate between 60 and 100. If the true mortality rate increases faster than my extrapolation, it would increase the rate at which you get a new "oldest person in the world". Without better data I can't check this. Anyway, +1 :) |
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Apr 10 |
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MATH PUZZLES involving chess board It depends how big the chess board is. Additionally, are you asking how many squares there are, or how many cubes? |
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Apr 5 |
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Why should a combinatorialist know category theory? You might be interested in combinatorial species, which are most naturally described as an endofunctor on the category of finite sets and bijections. |
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Mar 18 |
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Finding $\frac{d^2x}{dy^2}$ Do you know about implicit differentiation? |
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Mar 18 |
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how prove $\rho\wedge d\rho=0$ and how to show if $d(f\rho)=0$ for $f$ on $\Bbb R^{n}$ then $\rho\wedge d\rho=0$ Do you know any rules for expanding $\d(f\rho)$? If so, what happens when you take the wedge product with $\rho$? |
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Mar 1 |
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Incorrect use of the scaling relation for Brownian motion? Yes - when you compute ${\rm E}(XY)$ it can be true that $Y=_{\rm d} X$, but that doesn't justify the substitution $Y=X$ to get ${\rm E}(X^2)$. |
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Feb 26 |
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Eilenberg Moore category @TomEllis Something like newtype Algebra t a = Algebra (t a -> a) and newtype Morphism t a b = Morphism (a -> b) - so you don't actually need to pair a type with a value, it's implicit in the definition. So given an algebra $(a,h:Ta \to a)$ and a morphism $f:a\to b$ you can't actually return the algebra that the morphism maps to, but you can check that some morphism $f:a\to b$ is an algebra homomorphism between $(a,h:Ta\to a)$ and $(b,k:Tb\to b)$ by checking (modulo newtypes) that $k\circ Tf = f\circ h$. |
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Feb 26 |
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Eilenberg Moore category I suppose my issue is that I'm actually trying to implement these things - my intuition was that an algebra homomorphism should be a function that returns $(B,k)$ when given $(A,h)$, but clearly that doesn't have to be the case. |
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Feb 19 |
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KdV and forest dynamics As you say, there appears to be no information on the internet related jointly to the terms "KdV" (or "Korteweg de Vries" etc) and "Forest dynamics" (or "forest", "computational ecology" etc). There are three explanations I can think of: (1) there is a connection, but no one has written about it on the internet or published any papers about it, (2) whoever told you that the KdV equation models forest dynamics was mistaken, or (3) you misheard 'fluid dynamics' as 'forest dynamics'. I will leave you to assign your own relative likelihoods to those possibilities. |
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Feb 15 |
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Corroboration Of Simple Algebra For A Physics Lab All look right to me. |
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Feb 13 |
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Prove that $\left (\frac{a^2 + b^2 +c^2}{a+b+c} \right) ^ {(a+b+c)} > a^a b^b c^c$ @Iuli Answers that only include a link are bad, for exactly this reason - very often the page that was linked to disappears. Can you edit your answer so that it's useful again? |
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Feb 8 |
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Finding the ratio I like this more than my answer. |
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Feb 7 |
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What are the odds of the pattern “2 black, followed by 2 red” occurring in a roulette game? A quick comment - if your 'system' is one designed to win at roulette, you should be aware that rolls of a roulette wheel are random (and biased in favour of the house) and that there is no 'system' that consistently wins at roulette. If, on the other hand, you mean something else by 'system' then feel free to ignore this comment! |
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Feb 6 |
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Fit a semicircle in a distribution: MATLAB Then you need to modify the code appropriately! |
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Feb 4 |
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if $a= O(N^2)$, can I also say $a=O(N^4)$? I think the reason many people get confused with "big O" notation is that it's common to write $a(n) = O(n^2)$ when strictly it is more accurate to say that $a(n) \in O(n^2)$ (since $O(n^2)$ is a set, and $a(n)$ is an element of that set). Then since $O(n^2) \subset O(n^4)$ (as sets), it is trivially true that if $a(n)\in O(n^2)$ then also $a(n) \in O(n^4)$. |
