10-K Diver Profile picture
Oct 12, 2021 11 tweets 5 min read Read on X
1/

Ed Thorp (@EdwardOThorp) is a pioneer in the field of "how to recognize and take advantage of mis-priced bets".

This question has led Thorp to discover all kinds of fascinating and highly profitable strategies -- in Blackjack, Options Trading, Statistical Arbitrage, etc.
2/

In 2004 and 2005, Thorp published a 6-part article in Wilmott magazine.

In these parts, Thorp reminisced about his ventures into Statistical Arbitrage -- the science of profiting from the statistics of a large number of bets placed at once.
3/

I found this article to be an absolute gold mine.

It contains a wealth of investing/trading wisdom, plus a bunch of interesting nuggets from Thorp's extraordinary career.

👇👇👇
4/

Key insights/nuggets from Part 1:

- What does "market neutral" mean?
- How should we measure "risk-adjusted alpha"?
- Fundamentals of risk control via position sizing
- The importance of keeping transaction costs low ImageImage
5/

Key insights/nuggets from Part 2:

- What is "arbitrage"?
- Types of arbitrage: riskless vs risky
- The fundamentals of Statistical Arbitrage
- Are markets efficient? ImageImage
6/

Key insights/nuggets from Part 3:

- The importance of rigorous back-testing
- The fundamentals of Factor Analysis
- The founding of DE Shaw and Amazon ImageImage
7/

Key insights/nuggets from Part 4:

- Why size tends to be an anchor of returns
- The fascinating story of Thorp buying an oil tanker ImageImage
8/

Key insights/nuggets from Part 5:

- A precise definition of "haggling"
- Pros and cons of "haggling" while buying stocks
- Satisficers vs Maximizers: Good Enough vs The Best
- How Thorp got involved with Ken Griffin and Citadel ImageImage
9/

Key insights/nuggets from Part 6:

- Fund manager fees, alignment of incentives
- The importance of running a lean organization
- The marginal value of "Time" vs "Money" ImageImageImage
10/

If you want to learn more about Thorp, and about many other super-interesting characters who profited handsomely from asymmetric bets, I recommended the wonderful book "Fortune's Formula" by William Poundstone (@WPoundstone): amazon.com/Fortunes-Formu… Image
11/

Thanks for reading. I hope you enjoyed this thread!

/End

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Jan 1, 2023
1/

Get a cup of coffee.

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This is a classic exercise in probability theory.

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2/

In my mind, Gambler's Ruin is the math of "David vs Goliath" ("Skill vs Size") type situations.

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Get a cup of coffee.

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3/

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Imagine we have 2 companies, A and B.

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Get a cup of coffee.

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2/

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3/

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