Monty Hall Problem

Why don't you read bofa deez nuts?

>questions can be wrong
>I just want the original problem because I already know the answer based on someone else's work

MHP threads that subtly change the problem in meaningful ways are my favorite meme.

>bofa deez nuts
BOFA DEEZ NUTS EEEYYYYYYYYYYYYYYYYYYY

(also you're a faggot for not realizing that your change in wording does not change the question)

The correct answer is to stick with your original choice. You have a higher chance of success if you do. Think about it.

If you end up with the hot car, your chance of getting pussy increases since girls are attracted to money.

If you end up with the goat, well, you get a goat. But don't overlook the goat. A goat comes with 2 easily accessible wet holes and a 50% chance at a pussy.

Why would you pass up a guaranteed wet hole for a chance at a pussy?

>(also you're a faggot for not realizing that your change in wording does not change the question)
This is the pinnacle of pseudointellectualism. A retarded little user is convinced he is smart by "learning" meme problems without actually gaining any understanding. When you take off the training wheels, however, he keeps pumping the pedals with his chubby little legs and all the misplaced confidence of a youtube pickup artist, until he falls hard onto the hard cement and is brought back into reality by the splitting of skin and the squirting of blood, and all the pain of self-realizing his mediocraty had been sheltered from his whole life.

Bask in this user's shameless display of farcical pseudointellectualism. Soon he will realize what he truly is. A meaningless brick in the wall.

This is the pinnacle of pseudointellectualism. A retarded little user is convinced he is smart by "learning" meme problems without actually gaining any understanding. When you take off the training wheels, however, he keeps pumping the pedals with his chubby little legs and all the misplaced confidence of a youtube pickup artist, until he falls hard onto the hard cement and is brought back into reality by the splitting of skin and the squirting of blood, and all the pain of self-realizing his mediocraty had been sheltered from his whole life.

Bask in this user's shameless display of farcical pseudointellectualism. Soon he will realize what he truly is. A meaningless brick in the wall.

I don’t understand how this comment is constructive, or encourages the reader to think more deeply about anything. It appears to me that this comment’s only purpose is to display the cleverness of the author. Unfortunately, despite the collective efforts of the commentariate, we do get infiltration from those who are apparently determined to give the impression that they are incapable of parsing an entire piece of writing and reading it as a whole.
As has been previously noted (regular readers will be aware) we (that’s the “Royal we” — fellow commenters, occasional contributors such as myself and the moderator team) are engaged in an ongoing attempt to keep the quality of comments at its former impeccably high standard. Sadly, this is more of an effort than it should be.
And as a scientist, it is rather tiresome having to try to explain to the occasional numpty who happens across a post basic reading comprehension skills, how to follow an argument when it is constructed long-form and the ability to master data interpretation.
And I’ve just caught up on all the subsequent comments on this page. All the other commenters have managed to make coherent and intelligible contributions that furthered my understanding or gave me something to think about, because they took the trouble to type more than a single sentence. I don’t agree with everything that’s been said in other comments. Quite the opposite in a couple of cases. But at least I understand what was expressed and the intention behind it.

Look, if you're still going to troll or act retarded, that's fine.
- Swear
- Ad hominem; Call people names
- Don't provide counter-arguments
- Reject realism and the scientific consensus
That's ok.
Just don't loop.
Looping is cancer.

Personal incredulity and the argument from ignorance are fallacies. You're ignorant.
You imply you have no knowledge of the other kinds, therefore they don't exist.
That is wrong irrational.
:D

>random

Look guys, I changed it. But still called it MH. They are totally falling for it. I'm so clever.

>KYS

>It's exactly the same thing as the classical one, with the same explanation
>OP is correct, you have to read the question carefully
idiot

OK, I understand your autism wants to know what happened if the door were opened randomly and there just so happened to be a goat.

Well, this problem can be worked out by exhaustive thinking. The question is, what is the probability that a certain scenario played out and what should I do.

So, the probability that you chose a car straight away is 1/3 and then you shouldn't change. then you definitely see a goat, so the probability of you having chosen a car and seeing a goat on random is overall 1/3.

The probability that you didn't chose a car straight away is 2/3 and the probability that you're seeing a goat in this case is 50:50, or 1/2. Which makes this overall a 1/3 probability.
To check, the probability of seeing the car case you chose a goat is 50:50 (or again, 1/2) which multiplies to 1/3, which is pleasing since:
- the probabilites of this unrelated events add up to one and
- the chance of seeing a car overall is 1/3 which should be 1/3, since it's still a random guess

So now, if you see a goat, you are either in scenarion1 (having chosen a car straight away) or in scenario2 (having chosen a goat straigh away) both of these had the same probability to have occured 1/3, so they are equally likely.

Whatever you do, nothing changes, you may have the car or not with 50% chance.

[math] Show P(Win| Switch) \geq P(Win | Don't Switch)[/math]

[math] P(Win|Switch) = P(Picked Losing Door)[\math]

[math]P(Win|Don'tSwitch) = P(PickedWinningDoor)[/math]

[math] \forall n>2 [/math]

You switch, because it all depends on what door you picked at the start.

You only have to switch once, and you switch at the very end. It's actually easier to think of more than three doors.

Probabilistic intuition rather than Bayesian inference is more clear in this problem.

I deleted my earlier post where I addressed the probability of winning, but OP is correct, you have to read the question carefully.

and I deleted my fucked up Latex because I'm an insecure brainlet.

Yes you switch. Remember, you're initial door only has 1/3 probability being correct. That means everything else is 2/3. Therefore, if you can switch to the only remaining other door, you should for 2/3 of the chance.

>Monty Hall opens one of the doors randomly, and there happens to be a goat on the other side

Monty doesn't open the doors randomly, he will definetely open a door with a goat, and will definetely not open the car-door. Brainlets need to understand this, because that's essentially the reason why switching is always better.

Correct, if a bit convoluted. What is your bitcoin address user?

not interested

Anyone giving you a BTC address is pretending to be me and you can't really check now, can you...

Go buy shrooms with that money.

>the redditor doesn't it get
how surprising

the point of this thread is that the "always switch" answer only works if Monty knows which door has the goat. please see: en.wikipedia.org/wiki/Monty_Hall_problem#Other_host_behaviors

If Monty opened the door and showed you the car the game would be over though. You obviously wouldn't switch and take the money instead.

lol you don't get the rules of the scenario you retard. "look at me I changed the rules of an example to explain related probability so it is unrelated wow im so smawt".

New Game:

There are 4 doors. Behind 1 door is a car, behind the other 3 are goats.

After you pick a door, the host gives you a choice. He can either:
a) Open your door, if it's the car YOU WIN, if it's not you get to open one of the THREE remaining doors.

b) Open a different door that he knows contains a goat, and give you the option to switch to one of the TWO remaining doors.

What's your best strategy?

Ok I see your guys's complaint. It was unfair of me to hide the change and wasn't really my intent. This is the new image from now on.

kek

Answer of half the time switching wins makes sense, because you are observing one of two possibilities playing out, each with 1/3 probability.

>a) 1/4 chance to win plus a (3/4 * 1/3) = 1/4 chance to win. 1/2 chance overall.
>b) obviously less than one half since there are two optimal choices and one suboptimal choice

A.

b is equivalent to just ruling out one of the doors and switching your choice among the three remaining, so you have a 1/3 chance of winning.

a is 1/4 + (3/4)*(1/3) = 1/2 chance.

You have the same probability (.5) of switiching or staying the same.
Give he chose randomly and it happened to be a goat, the probability is split evenly between the two remaining doors.
Now fuck off

>There is always three doors and one car, so 1/3.
But it's either a goat or a car )two choices), so it's gotta be 50/50.

No. You could've initially chosen a car.

By switching you get an extra 66 percent chance of picking a car.

You must switch.

However this depends on how you define the sum of chance.

You could also interpret the next time frame as a fifty-fifty deal however as this is under the axiom of Monty hall is its own fucking time-space continuum. The correct answer is switch. 66 Percent chance of a car vs 33 percent certain goat.

How about this scenario. What would you do?

Randomly picks one of the three doors? 1/2:1:2
Randomly picks one of the two doors not chosen? 2/3:1/3

>No. You could've initially chosen a car.
I'm pretty sure you're wrong.
Forget goats and cars.
I'm going for a walk.
Two possible outcomes: either I get hit by lightning or not.
50-50, right?

999 goats sounds pretty cool desu

It's still 50/50

Correct
Correct, but you have the wrong probability for b.

Odds of picking correct on first time: 1/3
Odds of picking correct on second time: 1/2

First pick is meaningless. Only second pick matters. Therefore odds of picking correct is 1/2.

Example with 4 doors:
>Pick one of 4 doors.
>Host reveals one door with goat. Now there is 3 doors left and you can pick again.
>Pick one of 3 doors.
>Host reveals one door with goat. Now there is 2 doors left and you can pick again.
>Pick one of 2 doors. Other is goat, other is car, irregardless of your previous choices. You have no other information, irregardless of your previous choices.

You could do the same with 9999 doors and 9998 reselections. Only last selection matters.

Number of doors or proportion of goats/cars at the first pick doesn't matter.

Only thing that defines probability in this case is situation in the last pick.

The only correct answer here is a goat orgy.

a scholar and a gentleman ;)

Bravo sine

...

There's no value in switching. The key difference from the original Monty Hall problem is that in this case he randomly opened another door which happened to contain a goat, as opposed to selecting a door he knows has a goat. In this problem he could have revealed the car, in the original this wasn't possible.

You dense motherfucker.

How do you think the odds changed inbetween you choosing and him opening another door? Kill yourself.

Also, the question still works exactly the same whether Monty chose randomly or he chose deliberately if you're considering he's already opened a door. If you think otherwise you're retarded.

This might be the most retarded Veeky Forums post I have ever laid eyes on. Literally "Peanus Weenus" tier.

there's no reason to switch, and it's self evident.
[email protected]

Did babby not understanding something? What does babby need me to explain to you?

There's no reason not to switch either. He might be lying and just claim to have randomly opened one of the remaining doors. But in reality he knows which one has a car and didn't open it on purpose.

For your initial pick, odds are you picked a goat. So, if you want to play rationally, then you must assume you picked a goat.

When Monty opened the goat door, whether it was random or not, you received new information. You learned that one of the two remaining closed doors has a car behind it.

Since you are assuming that you initially chose a goat, then that means that the unchosen door is the car. So you switch.

This user is not retarded. Good for you, user.

There can't be this many 90 IQ Veeky Forums fags, can there be?

yes there is, it's a waste of fucking time. dumbasses

Explain why we're wrong then, you fucking tard. It's been spelt out pretty clearly why we're right, so why don't you take a shot at the title, camp.

now pay [email protected]
so i can buy some water balloons to throw right at Montey Hall's dick

The OP's problem is about the situation when a goat is revealed. If you are in this scenario, it is impossible to tell whether he chose randomly or not. Doesn't change the answer.

2

How about experimental data you fucking braindead mongrel? It should literally take you 5 seconds to run the possibilities through your head and realize you're dead wrong.
You can "tell" because it's stated to you explicitly in this hypothetical scenario. This isn't real life, user, it's a probabilities problem.

If he 'randomly' chooses a goat and only a goat, he hasn't 'randomly' chosen at all. The Monty Fool problem literally doesn't work unless you imagine the scenarios where he shows you the car, which OP was too retarded to do.

look, there is no explanation, you're either retarded or a genius. free will exists and we must be capitalists so the tards die off that means we must be anarchists

MIT already did it for me, retard. Spoiler alert: I'm right, you should kill yourself.

web.mit.edu/molly/Public/rsi2006/minisample.pdf

"The program was set to generate samples of one million games. In a half dozen runs,
the percentage of times the switching strategy proved successful ranged from 66.586% to
66.687%. The strategy of always staying with the original choice succeeded between 33.313% and 33.414%"

Yes because there is now a 1/2 chance if you switch

Imagine the host had a biased coin that lands heads with probability p (0

get the fuck out peter keating

>If the coin "randomly lands on heads and only heads, it hasn't 'randomly' flipped at all.
DAMAGE CONTROL MODE INITIATED

This might take the cake as the most retarded post in the thread, and that's saying allot.

>not recognizing that his isn't the Monty Hall problem

you appealed to someone else's retardation, you're a copy of a zero, that makes you a negative. MODS, ban this person

>peter keating
I didn't realise your taste in literature is as poor as your aptitude in statistics. What do you have to live for?

ok, i'm gonna make u think now.
the car's worth 15,999 dollars if u switch
it's worth 16 grand if you don't. do you switch?
[email protected]

That's literally what the words mean, user. Back to school for you!

So much mathlet butthurt. Just joking to be retards, right guys?

aab x
baa
aba

baa baaaab
aba abaaab

Not shoveling shit out of my own grave, unlike u, not even realizing that were all anonymous here

>Also, the question still works exactly the same whether Monty chose randomly or he chose deliberately if you're considering he's already opened a door. If you think otherwise you're retarded.
>web.mit.edu/molly/Public/rsi2006/minisample.pdf
JUST
>JUST
JUST
>JUST
JUST
>JUST
JUST
>JUST
JUST
>JUST

I don't even know what you're trying to say, you silly cunt.

Stop reading terrible books and pay more attention in class.

That supports my claim, you braindead cunt. My point was that Monty isn't choosing 'randomly' if you're only ever considering that he opens a door and the goat's behind it. Can't you read?

you sound like you're gonna shoot up a school

better yet, you sound like I'm not going to shoot up a school

Did my language hurt your fee-fees?
I'm not the one that reads Ayn Rand. Why would *I* be the school shooter?

>doesn't know what conditional probability is

that's because it took u 18 years to learn how to misinterpret the montey hall problem

> Doesn't know that I know what conditional probability is
> Doesn't know that he doesn't know what conditional probability is.

Sad!

if one more person in this thread says you should switch, I will literally climb a wall

> Can't even spell 'you' or 'monty'
> Thinks I'm less educated or capable.

okie-dokie.

I will climb it REALLY fastwastes its time learning how to spell a literal monster's name

> Thinks I have to put in effort to remember a five letter name
> Can't do the same by implication.

Wow, you're really retarded!

No, it absolutely does not. You are completely and utterly wrong in this, and nobody other than yourself has suggested ignoring the case where Monty chooses a car. The only reason we are talking about the case where he chooses a goat is because it's the only case where the guest is provided a choice to switch.

Here is the experimental data we get considering the possibility of Monty choosing a car (because why wouldn't we, are we fucking retards?)

>Car, Goat, Goat
>Choose door 1
>Monty chooses door 2 blindly
Switching is undesirable

>Goat, Car, Goat
>Choose door 1
>Monty chooses door 2 blindly
No choice to switch is presented

>Goat, Goat, Car
>Choose door 1
>Monty chooses door 2 blindly
Switching is desirable

Switching is desirable exactly half the times it is an option. This is catagorically and independently the correct answer to the problem in the OP. No arguments about wording or interpretations could be made since it was explicitly explained that Monty is a blind agent.

does anyone in here go to cal poly?

/thread

It is the new information of the location of a goat that causes me to switch, not the knowledge of the host. Assume you initially picked a goat, so don't take that door. The revealed goat is the 2nd the goat. Always switch to the third door.

If the host reveals the car instead of a goat, then you wouldn't have to make a decision because you already lost.

> Being this retarded

haha fucking kill yourself.
You ignore cases where monty chooses a car, because monty opens a door and shows you a goat. I'm sorry that the OP didn't grasp the logic of his images, and neither did you, but that's how language works. If he'd had said "open a door that may contain a goat or a car" you wouldn't be a retard, but unfortunately he did and you are.

I've got another "Monty Hall" type ?:
You're going to class tomorrow. There's, in this hypothetical situation, two school shooters on campus. There are three doors, you choose one, your imaginary friend chooses another one. your imaginary friend opens one of the other ones, there's a shooter there, in this hypothetical situation. Do you choose the other door?

Oops, there's three shooters, in this hypothetical situation, that doesn't happen tomorrow.

user, we ARE ignoring the cases where monty chooses a car, just like you said. It's still 50/50. Pic related is an excerpt from wikipedia.

You're wrong. Own it. Move on.

do you not understand me? tomorrow i'm running up a wall that's endowed with knowledge, your's. it's too late, I have your ip.