6.34 Lévy Distributions and Market Extremes
The Lévy distribution fits the body of returns far better than the Gaussian, with real power-law tails, and still misses the crashes. No single elegant curve captures the tail that kills you.
Author
ali askar
6.33 Fat Tails: Why Gaussian Thinking Breaks Trading Systems
The bell curve calls crashes impossible, and they keep happening, because real returns have fat power-law tails. Gaussian models fail in the crisis they exist for. Size for the move you can't model.
6.32 Variance Ratio Tests for Traders
For a random walk, variance grows linearly with time. The variance ratio compares real growth to that benchmark: above 1 trends, below 1 mean-reverts. It measures the past, not the future.
6.31 Random Walk and Efficient Markets Are Not the Same Thing
Random walk and efficiency are different claims, one statistical, one economic, neither implying the other. Reject the random walk without calling the market inefficient, and that's where edges hide.
6.30 How to Remove Yourself from Your Trading System
Removing yourself is engineering, not willpower: inventory where you intervene, close each point with pre-committed rules, automate what you can, and hand authority from the live you to the calm you.
6.3 Why Volatility-Adjusted Position Sizing Matters
Equal dollars isn't equal bets; the loudest instrument owns your P&L. Size inversely to volatility so each position carries the same risk, and the volatility you scale by is only an estimate.
6.29 The Discipline Premium in Trading
The discipline premium is the return for not making the mistakes everyone else makes. It can't be arbitraged away because instinct doesn't learn, but it multiplies a sound edge, not replaces one.
6.28 Why Discretionary Traders Need Rules Even If They Hate Systems
A discretionary trader without rules expresses skill laced with bias, and the two feel identical inside. Rule-bind sizing, exits, and re-entry, keep discretion for real reads, and test which is which.
6.27 Near Misses and Revenge Trading
A near miss feels like a stolen win, not a loss, which breeds revenge trading: re-entry sized by anger, timed by impatience. Break the loop with cooling-off rules and automation, not willpower.
6.26 Why Systematic Trading Feels Emotionally Unsatisfying
A working system is boring to run, and that's the barrier. It stops paying you in control and thrills, and the emptiness is the edge: every reward removed was a channel a bias used to cost you money.
6.25 The Illusion of Control in Active Trading
Active trading pays you in the feeling of control, disconnected from whether the market moves your way. Near misses and fast feedback amplify it, so the most engaging styles are the least profitable.
6.24 Why Traders Take Profits Too Early and Losses Too Late
Selling winners early and holding losers late is one asymmetry: prospect theory makes you risk-averse in gains and risk-seeking in losses, inverting a positive-skew edge into the blow-up shape.