to think the contestants on deal or no deal are a bit dim

[scoobytoo]

AIBU to think that you can't play or have a strategy for deal or no deal it's just pure luck and the people that the contestants that come with a strategy and a plan are barking mad

I think that anyone who goes on a gameshow is mental. And having a 'strategy' for picking the boxes is bonkers. However, I do believe that in terms of mathematics, the right 'strategy' at the end (if the banker offers you a chance to swap the boxes) is to swap. This is because at the beginning of the programme, the probability of you having the 'good' box in the middle was one in fifteen, but at the end the proability of picking the right box goes down to one in two. Therefore you discard the one in fifteen one that has sat there all along.

I think that's right but if any mathematicians want to come and put me right, that's fine by me.

Well, yes.

If they were bright, they'd go on who wants to be a millionaire or something

deal or no deal is 'eany meany miney mo' and frankly I can't watch it because the shit coming out of the participants and that vile little gnome's mouths makes me want to stick my boot through my tv!

Yes of course they're dim.

Sadly, so are the people who watch it every day and then describe what happened in stultifying detail to anyone unfortunate enough to be near them.

Yes I AM looking at you, FIL.

Sorry, SlightlyJaded, I don't think that's right (I'm also happy to be corrected!). At the end of the game you know what the two boxes are, so it's 50:50 which is which - it doesn't matter if you keep or swap! The 1 in 15 probability only applied at the beginning.

Are you thinking of that other Maths puzzle, where there's a game show with 3 doors - behind two are goats and behind one is a car. Obviously you want to pick the one with the car. The host asks you to pick one. He then opens one of the other doors to reveal a goat. There are now two doors left, and the host then asks you if you want to swap. The right choice this time is to swap (I won't say why straight away, in case people want to work it out!)

Oh and I tend to agree about Deal or No Deal, the strategy for it is to know when to quit - which all the ones I've seen they never do! But yes, the whole 'I've got a good feeling about box 5...' does annoy me.

It's utter, utter, utter mindless, ridiculous, slide down the food chain, devolve into plankton bollocks.

I keep saying this to DH (who watches it).

What they should do is just get the contestant to pick one other box and then decide which to open.

Voila, a mind numbing hour saved, someone has some money. All solved.

re: the three doors, well initially it was a 1:3 chance of picking the car. but now you know where one of the goats are its a 1:2 but not sure why you'd necessarily swop as the one you chose is also 1:2 at that point too.

As counter intuitive as it seems, it is statistically correct to swap in this problem, it's similar to the goat/car problem which is pretty well known BEACUSE it doesn't seem to make sense but it is mathematically true.

Can someone explain it then because I don't understand!

They get blinded by the big numbers, rather than working out the (often low) probability of picking the big number box imo.

here is the three door thing. It makes sense once you get your head around it.

Crikey! I still can't see how it works but it was interesting to read. I can't see that it's the same as Deal or no deal because there is no intervention during the game so wouldn't a swap have the same 1:2 odds?

hocus, think of it in terms of what would happen if you swapped or if you didn't whilst playing the game.

Right, so 3 doors, 2 goats and 1 car.

Assume that the car is behind door 3.

There are 3 possible scenarios.

Scenario one: you pick door 1. What would then happen is the host would show you the goat behind door 2. In this scenario, you should swap to win the car

Scenario two: you pick door 2. The host would show you the goat behind door 1. In this scenario, you should also swap to win the car

Scenario three: you pick door 3. The host shows you the goat behind door 1 or 2. In this scenario you should NOT swap to win the car.

So in 2/3 scenarios you should swap to win. Your odds are better if you swap.

Make sense?

Yes of course you are right orchid, that is exactly what I was referring too - duh. I remember doing probability at school and at the point where the teacher had drawn about 6 diamond shapes stemming from each other, I swtiched off. To this day I don't understand why, when you roll a dice, you don't have a one in six chance of rolling a six regardless of how many times you roll it. But I can live with that :)

Regardless, Deal or No Deal, is utter Twoddleshite.

Yes - sort of. I see that the odds are better when written out like that but in my head all I see is a 50:50 choice when one of the goats is taken out. I will think about it some more! Thank you!

I'm glad the door problem has interested people! Showaddywaddy has explained it very well.

I think the key difference between this and Deal or No Deal is that in the door puzzle the host knows where the car is, and chooses which door to open accordingly, whereas in Deal or No Deal, the contestant doesn't know the content of the boxes, and just chooses them randomly. If someone knew what was in each box, and opened all except the £250,000, and then offered the contestant a swap, the contestant should swap because they had a 1/15 chance of picking the £250,000 initially, so now there would be a 14/15 chance that it is in the one remaining box.

But doesn't that awful excuse for a host believe in Cosmic ordering ???

"I think that's right but if any mathematicians want to come and put me right, that's fine by me"

As others have said already you're thinking of "the monthy hall" problem. The difference there is that there is a known factor which increases your odds if you change doors which isn't present in the deal or no deal situation.

hocus, it's all about your original decision. There is only a 1/3 chance that you picked the door with the car behind it. There is a 2/3 chance that it is either of the others. The gameshow host very helpfully eliminates one of the other options for you so you are left with the one you chose (with its 1/3 chance of being right) or the other one that has a 2/3 chance of being right.

It's never 50/50.

22 boxes. 2 at the final stage.

-Assume you will definately swap.
If you've picked 250k, which is 1/22 chance, you lose.
If you've not picked 250k, which is 21/22 chance, you win.
Every 22 times you play, you would expect to pick 250k once and expect to have 250k in the last 2 boxes twice (22 x 2 = 44).
Of the two times that 250k is in the last 2 boxes, 1 time you will swap (and lose), 1 time you will swap (and win).

-Assume you will definately not swap.
If you've picked 250k, which is 1/22 chance, you win.
If you've not picked 250k, which is 21/22 chance, you lose.
Every 22 times you play, you would expect to pick 250k once and expect to have 250k in the last 2 boxes twice (22 x 2 = 44).
Of the two times that 250k is in the last 2 boxes, 1 time you will not swap (and win), 1 time you will not swap (and lose).

If you swap (or not), half the time you will win, half the time you will lose.
With the monty hall problem, 2/3 or the time if you swap you will win, 1/3 of the time you will lose.
The difference is that in EVERY game of the MH problem, a losing box is revealed and the player reaches the final stage.
In deal or no deal, 250k would only be at the final stage 2/22 or 1/13 times.