THE MONTY HALL PROBLEM

A game of probabilities and how it affects your trading

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πŸ•’ 9:04 PM

πŸ“… Sep 22, 2025

✍️ By chrison2

πŸ”Ή Monty What?

"The Monty Hall Problem" is a probability puzzle.

Named after the original host of the American TV show "Lets make a deal"

Here's the the setup πŸ‘‡πŸ½
You're on a game show with 3 doors:

One hides a car, the others have goats.

You pick Door 1.
The host, knowing what's behind each, opens Door 3 to reveal a goat.

He asks if you want to switch to Door2.




πŸ”Ή Probabilities

There’s a 1/3 chance your first choice is correct and a 2/3 chance the car is behind one of the other doors.

When Monty opens a goat door, switching gives you the 2/3 chance of winning, while sticking only gives a 1/3 chance.

How is this related to trading?


Should you switch?
Is it to your advantage?

πŸ”Ή Trading & Probabilities

As a trader you always choose the setup with the highest probable outcome.

It's the only way of being profitable.

But how do you define those probabilities?

They're based on the:

DATA GIVEN BEFORE ENTERING THE TRADE

πŸ”Ή New Information

In the Monty Hall Puzzle we are receiving NEW DATA AFTER choosing a door.

Without that information our probabilities of winning stay the same.

This highlights the importance of flexibility when it comes to trading.

Now, should you switch your bias?

πŸ”Ή Flexibility

Most traders get rekt because they ignore the flow of information.

Especially if they're new and their risk management is subpar.

Sticking to a bias with conviction is a necessity, just as much as being open to a change of directions.

Be water my fren!