- My Forums
- Tiger Rant
- LSU Recruiting
- SEC Rant
- Saints Talk
- Pelicans Talk
- More Sports Board
- Fantasy Sports
- Golf Board
- Soccer Board
- O-T Lounge
- Tech Board
- Home/Garden Board
- Outdoor Board
- Health/Fitness Board
- Movie/TV Board
- Book Board
- Music Board
- Political Talk
- Money Talk
- Fark Board
- Gaming Board
- Travel Board
- Food/Drink Board
- Ticket Exchange
- TD Help Board
Customize My Forums- View All Forums
- Show Left Links
- Topic Sort Options
- Trending Topics
- Recent Topics
- Active Topics
Started By
Message
re: Marilyn vos Savant and the history of the Montel Hall question
Posted on 2/23/15 at 5:30 pm to KosmoCramer
Posted on 2/23/15 at 5:30 pm to KosmoCramer
quote:I just realized that. They should randomize the door for the car. Regardless, if one didn't know that, the simulation would work. There are other simulators but the point still stands.
That simulator is crap. It's always in door number 1.
0
Posted on 2/23/15 at 5:31 pm to link
quote:You're sneaky. Regardless, it is a fun discussion (like the birthday problem).
agreed. keep an eye out for my annual monty hall question thread next january.
Posted on 2/23/15 at 5:49 pm to link
You were trolling. 
quote:
Whereas only 8% of readers had previously believed her logic to be true, this number had risen to 56% by the end of 1992, writes vos Savant; among academics, 35% initial support rose to 71%.
Among the new believers was Robert Sachs, a math professor at George Mason University, who’d originally written a nasty letter to vos Savant, telling her that she “blew it,” and offering to help "explain.” After realizing that he was, in fact, incorrect, he felt compelled to send her another letter -- this time, repenting his self-righteousness.
“After removing my foot from my mouth I'm now eating humble pie,” he wrote. “I vowed as penance to answer all the people who wrote to castigate me. It's been an intense professional embarrassment.”
Posted on 2/23/15 at 7:01 pm to Sid in Lakeshore
I meant to say Deal or No Deal, not let's make a deal
Posted on 2/23/15 at 10:04 pm to buckeye_vol
Predictably, this has already gone several pages. Here's the deal:
Let's assume there are n doors. You pick one, the chance your choice is correct is 1/n.
Now Monty proceeds to open all the doors you didn't pick except for one. Monty knows which one has the car, and will never open that door.
Trust Monty's advice.
Let's assume there are n doors. You pick one, the chance your choice is correct is 1/n.
Now Monty proceeds to open all the doors you didn't pick except for one. Monty knows which one has the car, and will never open that door.
Trust Monty's advice.
Posted on 2/23/15 at 10:11 pm to foshizzle
it's a fricking conditional probability problem
Posted on 2/24/15 at 2:32 am to foshizzle
quote:
Predictably, this has already gone several pages.
I love these threads. It took a couple for me to grasp the concept.
Posted on 2/24/15 at 4:06 am to Big Scrub TX
This again proves my point that most scholars are huge aholes. I worked in academia for a while and if it wasn't for the benefits I wanted to beat the ever living crap out of PhDs and professors on a daily basis.
Posted on 2/24/15 at 8:28 am to buckeye_vol
quote:
Monty Hall Simulator
I tried that and every single time I clicked the middle box it showed the exact same goat with the car in box #1 every single time. Very random
ETA: Didn't read other responses to the link yet.
I've seen the light; thanks to those who were able to help illustrate in a non-condescending manner. The case of 3 choices is perfect for the 50/50 illusion since you remove only one wrong answer. For cases with several initial choices I do see how the odds are affected, as it is impossible to get to a 50/50 scenario every single time where you have 100 initial choices and 98 incorrect ones are removed every time. Only an idiot would believe that out of 100 times of choosing one out of 100 that he would have picked the correct one originally 50 times.
This post was edited on 2/24/15 at 8:35 am
Posted on 2/24/15 at 8:40 am to link
quote:
I have to disagree with the "always switch" conclusion. The correct answer about the probability is that it is 50/50.
The problem is not in the math--it is that the setup and explanation of the problem always given is a cheat. The problem is changed in the middle, but the original probabilities are not. That is why it is so counterintuitive.
Those who discuss the probability in terms of 33% and 66% after the first door is eliminated are carrying forward into the new problem (where only two doors exist) information from the original problem, and thus not establishing anything more earth shattering than the fact that we originally had 66% goats and 33% cars to choose from.
In fact, the reason people commonly say the answer is 50/50 is that most people intuitively accept the initial premise that a door is simply removed from the problem--leaving two doors, known to hide a goat and a car. This is clearly a 50/50 choice.
You can appreciate this truth if you consider the person who comes into the game at the point where the contestant is told that there is goat behind one of the doors he didn't pick. That door is effectively removed from the game, as if it never existed. The new person faces simply two doors, with no knowledge about what has gone on before, and the certainty that there is one goat and one car. It does not matter which of the two doors he picks (or whether he "picks" one then "switches", or doesn't switch.) In the end, he chooses one door--and has a 50/50 shot at getting it right. Thus, for him, it doesn't matter if he switches or not--his probability is always 50/50.
Again, the problem with this riddle is that the mathematical explanations always start with the premise that you must carry forward the old 33/66 probabilities from the first problem into the second. That is the cheat--you don't. The Monty Hall problem really is a 33/66 probability problem changed into a 50/50 problem, but discussed mathematically (incorrectly)after the basic premise has been changed as if it is still a 33/66 problem.
Yeah i'm no mathematician but this seemed pretty obvious to me.
The odds change when the game show host changed them. Why would you stick with the original data when forming your answer?
Posted on 2/24/15 at 8:48 am to link
I haven;t read all the responses but in this game it boils down to your only having two strategy choices in the beginning.
1 - you can pick any one door and stick with it. ( = 1/3 chance of success)
2 - you can pick two doors and stick with it. (to do this one, you 'pick' one and switch to the other two = 2/3 chances of success)
No. 2 is really saying "I'll eliminate that door and take whatever is behind the other two."
1 - you can pick any one door and stick with it. ( = 1/3 chance of success)
2 - you can pick two doors and stick with it. (to do this one, you 'pick' one and switch to the other two = 2/3 chances of success)
No. 2 is really saying "I'll eliminate that door and take whatever is behind the other two."
Posted on 2/24/15 at 8:51 am to PygmalionEffect
quote:
blows me away that college educated people cannot immediately see that
Meh, it certainly isn't an obvious answer.
I like to break it down much further than 3 doors. Imagine 100 doors - 99 goats and 1 car - Door #37. You choose Door #42. Monty opens the other 98 doors leaving you with your choice and #37. Basically, if you stay, you're saying the other 98 doors being opened were irrelevant, because you stayed with your original choice. If you switch, your effectively giving yourself the chance to see 99 doors get opened, hence your chance of winning is 99% if you switch, and only 1% if you stay.
Posted on 2/24/15 at 8:58 am to slackster
well i simply dont agree with that. even if it makes me wrong.
when you remove 98 doors it changes the odds. i find it silly to pretend the odds are still 1/100 when you have changed the data.
when you remove 98 doors it changes the odds. i find it silly to pretend the odds are still 1/100 when you have changed the data.
Posted on 2/24/15 at 9:02 am to slackster
quote:
blows me away that college educated people cannot immediately see that
It's a particularly silly comment when you see that the problem has stumped and confused professors with PHd's in Mathematics.
Posted on 2/24/15 at 9:03 am to slackster
quote:
Meh, it certainly isn't an obvious answer.
True that - My original knee-jerk response was that it was 50-50. I actually had to do some analytical thinking to become totally comfortable with the real 33-67 result and how to explain it to kids.
Posted on 2/24/15 at 9:05 am to bbap
quote:
well i simply dont agree with that. even if it makes me wrong.
when you remove 98 doors it changes the odds. i find it silly to pretend the odds are still 1/100 when you have changed the data.
Is this sarcasm or what?
If you are serious, then every decision you make has a 50-50 chance of killing you = you either die or you don't.
Posted on 2/24/15 at 9:06 am to bbap
Say you play the game with 100 choices 100 different times. Each of those 100 different tries, 98 doors will be opened to reveal a goat. Do you believe you would have the car 50 of those times if you kept your initial choice every time?
Posted on 2/24/15 at 9:07 am to ChineseBandit58
quote:
Is this sarcasm or what?
no
quote:
If you are serious, then every decision you make has a 50-50 chance of killing you = you either die or you don't.
uh ok what a retarded analogy.
sorry but once you remove all the doors none of the original data matters. its the same as starting the problem with just two doors. just my imo (which obviously is wrong since savant says so.)
Posted on 2/24/15 at 9:10 am to bbap
bbap, I thought it would be 50/50 as well at first. But expanding the scope to several doors helped me better understand that it does in fact increase your odds of winning by switching. As a few posters (myself included) have suggested, try using MANY more doors (100, 1000 etc) and then remove every door with a goat except for your initial choice and the last remaining door. The more doors you add, the more clear it becomes that you do not have a 50/50 chance by staying with your initial pick every time.
Posted on 2/24/15 at 9:11 am to slackster
quote:
I like to break it down much further than 3 doors. Imagine 100 doors - 99 goats and 1 car
I haven't analyzed this problem in over 30 years, but this is the first time I have heard the explanation using an example of more than 3 initial doors. When you use the 100 door analogy, it does become immediately obvious that you should switch. I wish I had thought of that when my kids were asking for an explanation.
Page 5 of 7
Popular
Back to top
Follow TigerDroppings for LSU Football News