A brain teasing probability puzzle

Siddar

Bronze Baronet of the Realm
6,356
5,898
God damnit, some sadistic MMO Dev needs to sit down and find a way to structure loot distribution like this. I cannot even imagine the debates there would be in guildchat over this.
They would simply be told the right answer and would take the hosts box every time because tha'ts what the raidleader told them to do.
 

Erronius

Macho Ma'am
<Gold Donor>
16,491
42,458
They would simply be told the right answer and would take the hosts box every time because tha'ts what the raidleader told them to do.
GL Araysar: Look you stupid fucks, it's a 50/50 chance no matter what, just keep the cloth caps. Christ!
Raid: Fuck you, we want the other chest loot asshole!
GL Araysar: Seriously, it doesn't even matter anyways. The loot table is fucked, they're ALL CLOTH CAPS!!
RAID: Yeah, sure, blame the Devs! The loot table is fine, Brad said it's working as intended!
You have received [cloth cap].
You have been removed from the raid.
 

The Ancient_sl

shitlord
7,386
16
No, the host could just not offer you the option to switch at all. This happened on the actual show, and the OP does not say anything about how the host always opens a door, just that he did in this instance. Switching only benefits you if the host is forced to always reveal an unchosen booby prize regardless of what door you picked, and this is not made clear.
No, wrong. The original question posed is that the host reveals a booby prize. It does not matter if he knew the booby prize is there or if he always opens a door, once a booby prize is revealed your options improve by switching. The host's knowledge has nothing to do with it.
 

Ambiturner

Ssraeszha Raider
16,040
19,501
I'm not sure who's trolling and who's serious. It's starting to look like some people started off serious and now realized they were wrong and are going the "I was just trolling LOL" route. But of course it depends on the host always picking one of the boxes it isn't. That's why it says the host knows ahead of time which one has the prize.

This problem is essentially giving you 2 choices of the three boxes. It's also not like a coin flip where each flip is independent of the last, because the box the host opens depends on which one you chose in the first place.
 

Eomer

Trakanon Raider
5,472
272
Bro, if I didnt agree with the dozen other clowns who trotted this out, what makes you think I'll agree with you and the moose you rode in on?
Please explain why the second choice is independent of the first choice, when in between the host must only reveal a booby prize. The two choices are linked by the host's removal of one booby prize.
 

foddon

Silver Knight of the Realm
747
5
No, wrong. The original question posed is that the host reveals a booby prize. It does not matter if he knew the booby prize is there or if he always opens a door, once a booby prize is revealed your options improve by switching. The host's knowledge has nothing to do with it.
Exactly, you never get the choice if the good prize is revealed so it doesn't matter whether it's pointed out in the hypothetical or whether the host knows. The scenario with the choice only exists if the booby prize is revealed every time.

The question is really: you get to pick 1 door, the host gets the remaining 2... do you want your 1 door or the hosts' 2 doors? What's revealed doesn't matter.
 

Kaines

Potato Supreme
16,942
46,248
God damnit, some sadistic MMO Dev needs to sit down and find a way to structure loot distribution like this. I cannot even imagine the debates there would be in guildchat over this.
Wouldn't be hard to implement. When you kill BossMob3574 three locked chests spawn. The revs have already said that two of the boxes contains cloth caps and the third is a sword of aweomesauce. You choose one chest but it dosnt block right away. Instead a different chest opens revealing a cloth cap. You can them choose to go ahead and unlock the initial chest you chose or unlock the remaining chest you didn't choose.
 

Ambiturner

Ssraeszha Raider
16,040
19,501
Also, you're only chance of winning without switching is if you chose the right box initially. That's a 33% chance. If you choose the wrong box initially (66%) then you'll win by switching.
 

Loser Araysar

Chief Russia Correspondent / Stock Pals CEO
<Gaming Ghost>
75,767
150,446
I already did like 50x times in this thread.

Eomer should reread the thread.
 

Szlia

Member
6,572
1,328
I wonder how many pages we would have if the problem was an actual paradox that has yet to be convincingly solved. Like:

There are two indistinguishable envelopes. Both contain money. One has twice as much as the other. You can pick an envelope and keep its content. You pick one, but before opening it you wonder... should you open this one or switch? If X is the amount of money in your envelope, the other contains 2X or X/2 with equal odds, so the expected result of a switch is 1.25X: so you switch. But then you start to wonder... you can make the exact same reasoning with this new envelope and therefor find that the best course of action is to switch again... and again... and again. What went wrong?
 

The Master

Bronze Squire
2,084
2
At what point does the amount of money actually merit that much thinking about it? Because if it is like $1 and $2, I'll just grab one. If it is $10,000,000 vs $20,000,000 I'll just grab one, I'm set for life either way. There has to be some middle amount of money where you'd really want to spend the time on it.
 

Kaines

Potato Supreme
16,942
46,248
I wonder how many pages we would have if the problem was an actual paradox that has yet to be convincingly solved. Like:

There are two indistinguishable envelopes. Both contain money. One has twice as much as the other. You can pick an envelope and keep its content. You pick one, but before opening it you wonder... should you open this one or switch? If X is the amount of money in your envelope, the other contains 2X or X/2 with equal odds, so the expected result of a switch is 1.5X: so you switch. But then you start to wonder... you can make the exact same reasoning with this new envelope and therefor find that the best course of action is to switch again... and again... and again. What went wrong?
The amounts in the envelopes never changes, so while the average result of switching the first time is 1.5X, the result of a second switch is always X. The amount of money in the first envelope doesn't change and will always be X.
 

Melvin

Blackwing Lair Raider
1,399
1,168
I wonder how many pages we would have if the problem was an actual paradox that has yet to be convincingly solved. Like:

There are two indistinguishable envelopes. Both contain money. One has twice as much as the other. You can pick an envelope and keep its content. You pick one, but before opening it you wonder... should you open this one or switch? If X is the amount of money in your envelope, the other contains 2X or X/2 with equal odds, so the expected result of a switch is 1.5X: so you switch. But then you start to wonder... you can make the exact same reasoning with this new envelope and therefor find that the best course of action is to switch again... and again... and again. What went wrong?
First of all:
.5(2X + .5X) != 1.5X

Second, please stop abusing that poor defenseless X.
frown.png

Given:
2X = $10000
and:
.5X = $5000
solve for X...

Whoops again.
 

Xequecal

Trump's Staff
11,559
-2,388
No, wrong. The original question posed is that the host reveals a booby prize. It does not matter if he knew the booby prize is there or if he always opens a door, once a booby prize is revealed your options improve by switching. The host's knowledge has nothing to do with it.
Of course it does. He could simply only ever reveal a crap door and give the switch option to the people that picked the car, causing switching to lose every time.

In the OP, its only stated that the host revealed a shit prize in that one instance. It does not say he gave that option to everyone. The host could be trying to get you to lose.

Switching is only to your advantage if the host has no free will, and is forced to always reveal a booby prize and give the option to switch to every contestant.