If its like the statistics used in certain medical trials the probability of getting the prize is 0 as they will switch it from what ever you choose.
The have a show in the Netherlands called the "Postcode Lottery". After some silly stuff at the beginning, they go onto a game which has become known as "Deal or No Deal" in various countries around the world.
Basically they have a couple dozen closed suitcases (held by scantily clad women, of course
) each with an amount of money written inside, ranging from one cent to 1,000,000 dollars or euros. The contestant chooses one suitcase, then selects several other suitcases to be opened in batches. After each batch, the "banker" makes an offer based on what
might be in the contestant's chosen suitcase, which is recalculated based on what is known to
not be in the suitcase.
Thus after the contestant selects several suitcases, the offer will go up if low values are revealed (greater odds that there's more money in his or her suitcase), or go down if high numbers are revealed. So really, it never actually matters which suitcase the contestant picks, unless he or she is an idiot and insists on opening every suitcase on the stage, until it's known what's in the contestant's suitcase. What really matters is opening enough low value suitcases, to get a nice and high offer from the "banker".
So this should be a matter of luck, aside from knowing when to stop. And that's what happened every time I watched it in the US. But the first time I watched it in the Netherlands, the contestant who won some earlier rounds (trivia type stuff), had a bit of a surprise in store.
He had been watching the show closely for a very long time (probably years), and had come up with a system: he had observed that the same suitcase basically never have the big amounts in them, if they've had those big amounts in them before. Hence idiot contestants who think a number might be "lucky" because it held a big amount in the past would be likely to get 10 cents, or a dollar, etc.
So he started reading from his list, the numbers of the suitcases which had recently held big amounts, and they were opened up, one at a time. Before long, he had an offer of 300,000 euros or so, and stopped, even though his system seemed to be working wonderfully and he only opened up one or two with high values, and most high values were still on the board, and thus possibly in his suitcase.
If he'd kept playing (they had him keep reading his list, just to see), he would have had over 500,000 euros, but his suitcase ultimately had something less, if I recall, along the lines of 100,000 or less? Hence the host was inflicting a strong case of the "what-ifs", which are great for trapping the suckers that want to keep pushing, because they'd rather lose something that they never really "owned" than miss out on the opportunity to get a higher amount.
My thought was that it was much like playing a game of poker - as long as a good system is being used, and the player is sticking to it, they're making the "right" moves, even if they lose. The actual outcome on a specific game didn't matter as much as using the right system does in the long run.
I haven't watched the Dutch version of the show since that one remarkable game, but I'm willing to bet they've abandoned their old system of putting low amounts in the suitcases which recently held the big money.