Probablity Question

[southhampton]

I just wanted to do a quick poll/response forum on this topic.

I just wanted to see what people thought of this question:
Lets say there are 100 doors, and behind one of these doors is a car. Now the game show host eliminates every door except for yours (lets make yours #10) and door #47, but we know that the car is now between either door 10 or door 47 because he/she will not eliminate the car.

Does it matter if you change the doors?

I will post the answer later, I just want to see what everyone thinks of this.


By the way i copied this from another board because i was amazed at how many people got it wrong. wondering how smart the bevel is.

[CosmonautLaunchPad]

Unless there's some trick or wordplay here I'm just not seeing, it seems obvious.

[wutang]

I don't get why one of the doors is yours. If it's yours do you know what is behind it? Do yo mean does it matter if you switch the numbers on the doors? I just don't get the way it was written.

[rimrocka44]

I don't think it does, you still have a 50/50 shot if you switch doors or not. It's like on "Deal or No Deal", there are 2 cases left one with $1,000,000 and one with the other amount on the board, Howie gives you a shot at swapping cases, but do you do it? Deal or No Deal???

[CosmonautLaunchPad]

rimrocka44 said:

I don't think it does, you still have a 50/50 shot if you switch doors or not. It's like on "Deal or No Deal", there are 2 cases left one with $1,000,000 and one with the other amount on the board, Howie gives you a shot at swapping cases, but do you do it? Deal or No Deal???

Well if I understand correctly it's a lot different from Deal or No Deal. At the start, if you're picking one door, you have a 1 out of 100 chance of picking the door with the car behind it. Now the dealer or host eliminates every door but yours and one other door and the car has to be behind one of them. The odds the first door I picked (if I picked before all the other doors were eliminated) contains the car aren't very good. Odds are it's behind a door other than the one I picked. 99 out of a 100 chance it's a door other than the one I picked. So if I'm offered the choice of switching if that's the way it plays out, hell yeah I'm switching doors.

[wutang]

Ok so you pick a door then 98 are eliminated, leaving the one you picked and another and one has the car. Cosmo sounds right then. I didn't get the "your" door thing means you pick a door to start off with when there are 100 of them. It read to me like somehow you already had a pre assigned door or something and they would narrow it down to two for you making it a 50/50 shot.

[vinnypunditsheros]

I looked at it as Deal or No Deal first too but I agree with Cosmo.

I hate that show. No logic or skill involved, just picking boxes at random.

[The Dull House]

ON deal or no deal you are picking every box, so switching at the end doesn't matter. But since we know in this case that the host won't pick the car box and eliminate it, one would have to assume to go with his Box or Door at the end. It's like Howie Mandel eliminating Boxes himself after you picked one. Of course you go with Howie.



So Cosmo I agree with you. I switch doors

[CosmonautLaunchPad]

vinnypunditsheros said:

I looked at it as Deal or No Deal first too but I agree with Cosmo.

I hate that show. No logic or skill involved, just picking boxes at random.

The skill involved in that show is knowing when to quit. And none of the contestants have any skill in this department. Some fat fucker the other day had an offer of over 200 thousand and kept going because an idiot friend kept telling him to. He went home with 10 dollars.

That being said, watching the show I always know when the right time to quit is, but would it be so easy if you were actually up there on that stage? Who knows. I do know one thing though. I would only have people up there to advise me that would directly benefit from me getting a lot of money. That being family members and such. The mistake so many people on Deal or no Deal make is having friends up there. It's sad to say, but sometimes friends are secretly routing for you not to win. They don't do it because they are evil or bad friends, but it's just human nature sometimes deep down be a little jealous of friends when they have some good fortune. Friends might secretly give you bad advice to subconsciously sabatoge your attempts at making money. Case in point, this fat ass's sister was telling him to deal over and over again and his friends were saying, keep going keep going. They didn't care.

Anyway, I think I've wasted enough brainpower analyzing deal or no deal for one day.

[s dot carter]

The answer is yes but I think I voted 'no' today because I'm an idiot. Either way, I'm right.

[The Dull House]

The trick to deal or no deal is to

1) have a set limit you want to walk away with
2) Once their is only one high amount left you should walk away since is skewes the offer.



But I don't know if I could do that or put together a coherent sentence. Have you ever looked at those briefcase girls? Oooooh la la !

[southhampton]

You should switch doors.

Lets say the car is behind door number 12, you have a one in a hundred chance of getting that right on your first guess. If you do not get it right though, 99% of the time you wont, 12 would be the other choice the host gives you, making it in your best intrest to switch.

The only time it is good not to switch is when you guess right on the first try, which is only 1% of the time.

[rimrocka44]

southhampton said:

You should switch doors.

Lets say the car is behind door number 12, you have a one in a hundred chance of getting that right on your first guess. If you do not get it right though, 99% of the time you wont, 12 would be the other choice the host gives you, making it in your best intrest to switch.

The only time it is good not to switch is when you guess right on the first try, which is only 1% of the time.

But what if door #10 was that 1% of the time???

Where did door number 12 come from? I thought it was down to door 47 and your pick of door number 10. You already beat 98% of the odds, whats one percent more?



"One in a million...so you're saying there's a chance"

[CosmonautLaunchPad]

southhampton said:

You should switch doors.

Lets say the car is behind door number 12, you have a one in a hundred chance of getting that right on your first guess. If you do not get it right though, 99% of the time you wont, 12 would be the other choice the host gives you, making it in your best intrest to switch.

The only time it is good not to switch is when you guess right on the first try, which is only 1% of the time.

You could have just copied and pasted my answer South.

"I am so smart! I am so Smart! I am so Smart! S-M-R-T, I mean S-M-A-R-T!!"
-Homer

Someone even got it wrong after I gave the answer away.

[rimrockajrbitch]

its one of those wordy questions its not asking you if u change the car place its asking if u change the door the door doesnt matter at all so i think u could change it and the car would still be in the same place right?