| 00:00 - 00:03 | The Monty Hall problem from the game show Let's Make a Deal! |
| 00:04 - 00:05 | There are three doors, |
| 00:05 - 00:07 | Behind one of them is a car ... |
| 00:08 - 00:12 | And behind other two doors are goats. |
| 00:12 - 00:15 | So let's play. Choose a door number: |
| 00:17 - 00:19 | I'll take door number ... |
| 00:19 - 00:21 | ONE. |
| 00:24 - 00:26 | The host, |
| 00:27 - 00:28 | Monty ... |
| 00:31 - 00:33 | Monty Hall will show you a goat behind door #3. |
| 00:34 - 00:36 | Do you want to switch your choice? |
| 00:53 - 00:58 | Anybody who knows Probability and Statistics, or Math majors, can leave. |
| 01:13 - 01:15 | Why the hell would I change my choice? |
| 01:15 - 01:17 | You asked me what I wanted for my choice ... |
| 01:18 - 01:23 | And I picked Door Number 1. ONE! |
| 01:25 - 01:28 | I think the car is behind Door #1. |
| 01:29 - 01:31 | WTF? Goats!! |
| 01:31 - 01:34 | Why would I change my pick? |
| 01:34 - 01:37 | I don't want any stupid goats! |
| 01:37 - 01:40 | I WANT THAT EFFEN CAR! |
| 01:40 - 01:42 | But if you switch, you'll double your chances ... |
| 01:42 - 01:46 | It's a 50-50 chance. I'm staying with door #1. |
| 01:46 - 01:48 | You're more likely to win if you switch. |
| 01:48 - 01:52 | How the hell is that even possible? |
| 01:53 - 01:54 | There are now two doors. |
| 01:56 - 01:57 | The one I picked ... |
| 01:57 - 02:00 | ... and door number two. |
| 02:00 - 02:03 | That's only two outcomes in the sample space. |
| 02:04 - 02:08 | Aren't we assuming independent events? |
| 02:08 - 02:13 | Let A be the event of winning the car, and B be the event of getting the goat. |
| 02:14 - 02:16 | Don't tell me it's one of those conditional probability formulas. |
| 02:17 - 02:21 | So P(A) is the number of successes divided by the number of outcomes. |
| 02:27 - 02:29 | And 1 over 2 is 50%. |
| 02:30 - 02:34 | How am I not right? Is that not the final solution? |
| 02:34 - 02:36 | Jesus, how I hate mathematics. |
| 02:41 - 02:42 | Let me think ... |
| 02:43 - 02:47 | There are three choices I, the contestant, can make. Doors 1, 2 or 3. |
| 02:48 - 02:53 | And another three places that douchey host can hide the car. |
| 02:54 - 02:56 | So that makes 3 times 3, which is ... ? |
| 02:56 - 02:59 | Somebody get me a calculator. A graphing calculator. |
| 03:00 - 03:02 | And not that Casio P.O.S., I want a TI-89! |
| 03:04 - 03:07 | It's okay, we'll just ask Siri on the iPhone. |
| 03:14 - 03:16 | Wait a minute ... that's nine possibilities. |
| 03:19 - 03:23 | And half of nine is 4.5. How can there be four and a half doors? |
| 03:25 - 03:26 | It can't be 50-50. |
| 03:31 - 03:33 | At first it was a 1/3 chance of winning, |
| 03:40 - 03:46 | A 66.6% chance of losing. So if I stay with Door One, I win 33.3% of the time. |
| 03:46 - 03:49 | I should switch to Door Number TWO, doubling my chances to 66.6%. |
| 03:53 - 03:56 | Maybe I want the goats. |
