The Monty Hall Paradox

	Duration: 09:10 minutes Upload Time: 2007-03-11 01:47:24 User: TheMathGuy :::: Favorites :::: Top Videos of Day
Description: A probability question the answer to which may seem paradoxical. ( Aside: I now have two YouTube channels. This one will be primarily for intellectual/mathematical pursuits and response videos to other YouTubers, the other channel, http://www.youtube.com/profile?user=NathanaeLman will be about the "behind the scenes" me--and will include whatever I feel like talking about, boring or interesting, mathematical or not, whether anyone's watching or not. )
Comments
bikaz28 ::: Favorites You can hear the keys under the cup when he moves the cups. lol It was easy to know what cup the keys were under. 07-10-04 13:08:52 __________________________________________________
LinkTetraWW ::: Favorites That makes sense to me. I took seven years of math in highschool and never did I hear about this. Thank you, TheMathGuy. 07-09-21 00:27:54 __________________________________________________
tttooommm123 ::: Favorites think of it in a case of 100 doors you pick one door and you have a 1/100 chance of being right, that means that the other 99 doors have a 99/100 chance of being right, when monty hall removes 98 of those doors revealing nothing, and that still leave the one door that you didnt pick with a 99/100 chance of being right, so you switch 07-07-30 22:54:28 __________________________________________________
izeman458 ::: Favorites I already figured it out a couple of days ago. All these videos with their wacked out analogies are just shitty at explaining it. That is why so many people stay confused and disbelieving. I figured it out by running a simulation in my own head of the original monty hall paradox. 07-07-30 00:58:49 __________________________________________________
1Brockster15 ::: Favorites 2. The prize still must be ELSEWHERE 2/3 of the time. When the host of the show performs the NON-RANDOM act of showing you which one of the ELSEWHERE doors doesn't have the prize, this of course remains true. Again, the prize is behind the ELSEWHERE doors 2/3 of the time; the host simply shows you which one of them doesn't have the prize. 07-07-29 09:43:32 __________________________________________________
1Brockster15 ::: Favorites 1. Think of it this way: After the first door is chosen, what is the probability that the prize lies ELSEWHERE (behind either of the two other doors)? It's 2/3. If the host, who knows where the prize is located, makes sure to open the particular "ELSEWHERE door" behind which there is no prize, it remains true that the prize will NOT be behind the original door that you chose 2/3 of the time. This fact cannot be changed. 07-07-29 09:42:21 __________________________________________________
izeman458 ::: Favorites I agree, I don't buy it either! The two doors that are left both have an equal chance of holding the car. That equal chance used to be 33% versus 33% and after eliminating the third door that equal chance has now become 50% versus 50%. I know people say its just my intuition but its intuition + logic as I just explained. 07-07-18 03:22:50 __________________________________________________
mayyn94 ::: Favorites THANKYOU!!!!!! 07-07-17 08:08:36 __________________________________________________
babajacob ::: Favorites mayyn94 is correct, in my opinion. Probabilities are information sensitive. The fact is that once the game show host takes one door away, the original 1/3 probability no longer applies. Why? Because there is new information and we are now making a new choice (whether that choice is to stick or change is irrelevant) based on that new information. There are now two doors so the probablility is NOW 1/2. It is plain and simple. Trying to bring in the previous 1/3 to 2/3 probability is fallacious. 07-07-17 01:42:48 __________________________________________________
mayyn94 ::: Favorites but its not a 1/3 problem if you get rid of one. its a 1/2 problem. you choose one, and the host gets rid of one. that means theres really only a 1/2 chance you'll get it no matter what. if you change your mind, theres still a 1/2 chance. tom and bob have 50% chances no matter what. forget the 1/3 chances in this. there is no 1/3 if the host always takes one away. by the way, i dont know what im talking about. dont listen to me. 07-07-12 10:54:12 __________________________________________________