The Monty Hall Problem

[RSE]

Suppose you are on Let's Make A Deal, and Monty Hall shows you three doors. Behind two doors are booby prizes, behind the third a million dollars. You choose Door A. Monty then shows you that behind Door C is a booby prize and asks you if you want to switch to Door B or stick with Door A. What do you do?

[TerpEagle]

Suppose you are on Let's Make A Deal, and Monty Hall shows you three doors. Behind two doors are booby prizes, behind the third a million dollars. You choose Door A. Monty then shows you that behind Door C is a booby prize and asks you if you want to switch to Door B or stick with Door A. What do you do?

I've heard this problem. I think it depends on what perspective you choose, but you pick the other door in the second round.

Your first choice had a 66.7% probability of being a dud so a 33.3% success rate. You now have the option at a 50% success rate - your odds have improved so you take it.

[Susquehanna Birder]

You just had to start that shit again, didn't you.

[RSE]

People are bored here? This is worse than being bored.

[PackWest]

Suppose you are on Let's Make A Deal, and Monty Hall shows you three doors. Behind two doors are booby prizes, behind the third a million dollars. You choose Door A. Monty then shows you that behind Door C is a booby prize and asks you if you want to switch to Door B or stick with Door A. What do you do?

If you're an Igglephan, you pull out your gun and press it against Monty's temple.... and tell him to choose for you.

However, if you're KG, you happily take the booby prize

[Susquehanna Birder]

People are bored here? This is worse than being bored.

Bwah...yeah, it's a "be careful what you wish for" thing.

[Overbrook]

Level of agreement (c) 100%

You just had to start that shit again, didn't you.

We had this solved years ago. 🐸 (I just now discovered this frog on my iPad, so I put it in here)

The correct answer, as I recall, is to beat Bob over the head with a 5 iron until he coughs up where the prize is.

[Loki]

bwahahaha

Pigfucker!

[Two Gap Penetrator]

Hitler

[Loki]

Or play him Bonnie Raitt songs until he just gives you all the shit

[Drama Queen]

Hahaha.

[common wealth]

I've heard this problem. I think it depends on what perspective you choose, but you pick the other door in the second round.

Your first choice had a 66.7% probability of being a dud so a 33.3% success rate. You now have the option at a 50% success rate - your odds have improved so you take it.

The odds of your first choice being right or wrong do not change. I agree you switch, but if you do your odds of being right are 2/3, not 1/2

[TerpEagle]

The odds of your first choice being right or wrong do not change. I agree you switch, but if you do your odds of being right are 2/3, not 1/2

Is that because once one poor choice is removed, the odds of an original poor choice (2/3) are multiplied by 1/2 thus becoming 1/3?

[IronEagle]

Is that because once one poor choice is removed, the odds of an original poor choice (2/3) are multiplied by 1/2 thus becoming 1/3?

It's because Monty has knowledge and by using it to show you a booby prize whether or not you originally selected the winning prize he takes randomness away.

You originally had a 1/3 chance of selecting the winning prize. If you didn't originally select the winning prize and selected a boob, Monty has to show the other remaining booby prize. So by switching your odds go from 1/3 to 2/3. In other words, if your original selection was not the winning prize, by switching you win the prize.

Let's say the prize is in door 1.

Case 1: You originally pick door 1. Monty shows you a boob in either door 2 or 3. You switch = BOOB

Case 2: You orginally pick door 2. Monty has to show you door 3 since door 1 has the prize. You switch = WIN

Case 3: You orginally pick door 3. Monty has to show you door 2 since door 1 has the prize. You switch = WIN

Thus in 2 out of 3 cases a switch equals WIN and 1 out of 3 equals BOOB.

It's simple algebra.

[Irish George]

Jeffrey Dahmer

Jeffrey Dahmer