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Ok, who hasn't heard about this movie has either been living under a rock, or has probably been pronounced dead. ^^

This movie, was based on an old book I read - Bringing Down The House, which tell the true story of a group of MIT students who were smart enough to bring down Vegas.

Unfortunately, that kinda tactics cannot really be used in our modern society, what with facial recognition technology and also those lie detectors and what not.

This movie has yet to be released in Malaysia, for it contains many "sins". Sex, Money and Gambling. Go figure. LoL.

I rate this movie only a 6.5/10. While fun to watch, it does not have that WOW effect. Well don't take my word for it. [SAM] says that it was the best movie he watched this year.

Now onto another issue from the movie.

This movie contains a scene around the 15th minute, whereby, the teacher asks the student :

T : Let's say this is a gameshow, and the host presents you with 3 doors. Behind ONE of the door, there is a brand new car. The other 2? Goats. ^^. Go ahead and pick a door.

S : Door 1.

T : Okay. Let's see. (and the host opens Door 3 to reveal a goat). So, do you want to change your answer?

S : Yes. I change my answer to Door 2.

T : Why? Enlighten us.

S : Well, simple. If I change my answer to door 2, I have a 66.6% chance of getting the car. But if I stay with my previous answer, I will still only have a 33.3% chance. It is not a definite win, but logically, people will go for the higher chance.

Now. Most of you may be wondering WHY is there 66.6% chance if he changes his answer. Simple. This theory has been revealed a long time ago. AND, many PHD owners and lecturers and mathematicians and stuff also got it wrong. So do not blame yourself if you do not understand it.

First, let me say, that there is NOTHING wrong with this example, it's calculations and also the answer. It is perfectly correct. Though a little hard to understand. ([SAM] says it is inefficient. I still don't really know what that means).

So for the purpose of discussion. Here is why.

First, when you were given the choice, you had a 33.3% chance of getting it right, AND a 66.6% chance of getting it wrong. In simple words, the odds are AGAINST you. Right?

So the host opens door 3. Right now, most people think that you currently have a 50-50 chance of getting it right, right? And it doesn't matter whether or not you change your answer?WRONG.

Take a look at this 2 pictures.

That is your initial chance, whereby the odds were AGAINST you.

And THAT is your chance if you decide to switch. Why? Because one door was already opened, and as such, if you switch your answer to door 2, you will have the odds on YOUR SIDE. Understand? Why? Because, you have to know that the host cannot open YOUR door or the WINNING door right?

Of course this does not guarantee you a win. But which fool will go for a lower chance if there is a higher one? So, to put it simply, you WANT a higher chance of winning. And as such, you MAKE the switch.

If you do not understand, allow me to explain it another way.

Let's say there are 1,000,000 doors. The player picks a door. The game host then opens 999,998 of the other doors revealing 999,998 goats—imagine the host starting with the first door and going down a line of 1,000,000 doors, opening each one, skipping over only the player's door and one other door.

The host then offers the player the chance to switch to the only other unopened door.

At the start, YOU had 1 chance of getting it right, and 999,999 chance of getting it WRONG. So now, if you switched, you would have 999,998 chance of getting it right. A rational player should switch.

As I said earlier, this is very theoretical. It does not necessarily have to work out that way because there is the element of luck involved. But lets say you put all emotions aside, and follow statistics, you would choose to make the switch.

This is called the Monty Hall Problem. I did not create it, nor do I endorse it. I just somehow understand it. If you do not understand, go take it up with the dead man himself. I am not here to explain. Or you can also Google it. As they say, many many very highly educated men also have a hard time understanding it. ^^

*We have also learnt something like this in Form 4/5 whereby you have 2 kinds of situation. One whereby you can repeat the outcome and one where you cannot. Both have very different percentages.*

Have fun racking your brains. Cheers.