1/ A thread about the relationship between getting older and learning new things.
🧵👉👉
2/ It’s a weird relationship. One way of looking at it is through the lens of the explore-exploit tradeoff.
3/ In reinforcement learning, when you have to act in a novel environment and learn in an online way, there's a tension between trying new things vs doing the things you’ve already learned are good.
4/ When you’re new to an environment, you know nothing so you’re better off spending all your time exploring.
But when that environment is pretty well-known, exploration doesn’t buy you much and so you should focus on exploiting the things you’ve learned already.
5/ Figuring out that tradeoff in general is a hard problem.
This is all pretty well-known.
6/ And this is what we do already in life. When allowed, kids spend all their time playing, exploring, and generally learning about this new environment called “the universe”. In fact, their brains are wired to do so.
7/ Conversely, old ppl will get less value from trying new things, supposedly, so they stick to what they know.
In the ancestral environment that makes sense, since that world wasn’t nearly as diverse as ours is today.
Which is why old people can seem “stuck in a rut”.
8/ I see this happening to myself too.
When I was a kid, learning about a new thing felt like “Ooh, new thing! Let’s learn about it!” I see it in my kids. But for me, now the reaction usually “Oh, new thing. It’s probably dumb.”
But, what does that transition look like?
9/ I claim it goes in 3 stages:
A. New thing, I like learning new things.
B. New thing, sounds interesting but I’m busy. I’ll look later.
C. New thing, I know nothing about it. Not worth my time.
10/ A -> B happens because life happens. You leave school, get a job, and it’s your time in life to make hay.
“Get ahead in life” by doing the important things. Start exploiting!
11/ But why does B -> C happen?
I claim it’s caused by A -> B. The more new things you pass up on learning about, the harder it gets to learn about subsequent new things! You fall farther and farther behind.
12/ The easiest place to see this is old ppl and tech. Even ppl who lived a whole career doing tech fall victim to this. My dad, for example.
They slowly fall behind, and now they’re 10 years+ behind and there’s no chance of getting them to jump on a Discord server or Tiktok.
13/ If course if you ask them, they’ll tell you “it’s stupid”.
And it is, to them, but that’s partly a post-facto justification for the fact they don’t know about it, or don’t care to learn.
14/ Case in point: my relationship with crypto and DLT.
I’ve known about it for over a decade now. When it first came out, I thought “wow, that’s cool, I should look into it”. And I did a bit, enough to learn how the tech works, but then I ignored it.
I was busy.
15/ Fast forward a few years, and it’s clear that crypto trading was a thing. But by then my instinct was:
“Bah, crypto has no obvious economic value, I’ve got better things to trade.”
And I probably would have left it at that except for two lucky facts.
16/
A. I have younger friends, ones who aren’t as far along on the ossification spectrum.
B. I like making money. I’ll learn anything if there’s EV there.
17/ So I started. Now a few months into the journey, and I’m still faced with the same learning problem.
“MEV, what’s that? Sounds weird, I’ll stick to my CEX trading.”
“NFTs? So stupid, and plus you can’t even get short. Forget it.”
18/ Do I *have* to learn this?
Then I start, and I remember that I *like* learning.
And that “what’s important” isn’t written in stone.
19/ What's important changes, and the only way you’ll figure out the new important things is by learning some things that feel dumb and worthless.
If you’re never learning stupid stuff, you’re not learning much.
20/ And so it goes. I have to keep reminding myself I’m not a hunter gatherer. The world I live in is so rich in opportunities, and getting richer all the time.
100% exploit, or even 85%, is just clearly too much.
True at age 45, and it’ll be true at age 85.
21/ The good news in all of this, for older people, is that old knowledge is VALUABLE.
Some of the biggest joys and best trades happen when old knowledge is applied in new areas. Because usually those new areas are being created by young people who don’t have much experience.
22/ An old person being flexible enough to learn new things, and partnering with younger people, is the great sweet spot where anything can happen.
ps. Don’t yell at me about old/young. Y’all know what I mean.
/END
Addendum because I already got a DM about it: the people I most like to read on the Twitter are people who seem enthralled with learning new things.
The better the trader, the less they care about which specific product/market they're trading.
That doesn't mean they don't have deep knowledge of the market or product. Far from it.
It means they don't *care*.
2/ Conversely, I see a lot of aspiring, new, and frankly bad traders who care a *lot* about the product.
"I trade options," "I trade futures" like it's a religious commitment. It's not. The product you're trading is a means to an end, at least if you care about money.
3/ One of the founders of my former company loved saying something like:
"If they made financial markets illegal tomorrow, we'd probably suffer for a while but we'd eventually be fine. We'll just go find something else to trade."
There’s a subtle but very real fallacy about backtesting that lots of smart quant-y people fall into. I’ve fallen into it many times. And arguably I still do, just in more and more subtle ways.
A thread 👉👉
1/n
So you have a trading strategy, and you want to backtest it to see if it’s any good. Being good boys and girls and others, we know we mustn’t overfit to the data we already have.
We know that historical data is precious gold, and it must be used carefully.
2/n
Well, imagine I propose the following solution: build a model of the market in all its gory detail: fat tails, heteroskedasticity, vol clustering, etc etc. I calibrate this model using historical data, and it’s pretty good.
"In all honesty, most finfluencers have pretty shit takes on the market. It kind of arises based on the mismatch between the skills required to actually trade and the skills required to market oneself."
"I'm a smart engineering/CS/math student/graduate. How do I get into quant trading?"
A thread. 👉
1/n
2/ I'm going to preface this by asking an important question:
Why trading?
Almost every outsider has an idea of what trading is that's pretty far from the reality. It's not "deploy cool ML models on gigabytes of data". It's:
3/ - Do I have enough cash margin in account JP44315A?
- Why does the data format disseminated by broker X suck so much with this new update?
- How do I optimize my tax footprint?