Unutterably Silly Quiz

[orlok]

Originally Posted by pdurrant

Only Connect is a rather good quiz show. The only other quiz show on TV I like at the moment is Pointless, where the aim is to get an answer to a question that no-one else (in a survey of 100 random people) got.

Yes, I like Pointless too. I was happy to say at the start of the series that it was aptly named, but soon got drawn in and now watch it every chance I get.

I'm not going to have a guess at the quiz just yet - it's too late in the day, and I'm trying not to get too distracted from my writing (damn you MR), so I'll have a think again in the morning if one of our currently sleeping friends don't get there first.

[orlok]

OK, I give in, I'll have a go...

I would put £5 on one of the 50/50 bets (let's ignore that inconvenient zero for a moment), so Odds or Evens, Black or Red, first 18 or second 18. If that wins, I'm out of there with my £160.

If it doesn't win, I'm now left with £150, so I'll double my bet, and put down £10 on a 50/50 bet. If I win, I've got my £160. If not, I again double my bet, and so on until I either get my £160 or am wiped out.

[pdurrant]

Originally Posted by orlok

OK, I give in, I'll have a go...

I would put £5 on one of the 50/50 bets (let's ignore that inconvenient zero for a moment), so Odds or Evens, Black or Red, first 18 or second 18. If that wins, I'm out of there with my £160.

If it doesn't win, I'm now left with £150, so I'll double my bet, and put down £10 on a 50/50 bet. If I win, I've got my £160. If not, I again double my bet, and so on until I either get my £160 or am wiped out.

Yes, I believe that is indeed the best strategy. one point to you.

For two points, what are the odds of getting £160? (& no, you may not ignore the zero*!).



*European table. No double zero. (Greedy American Casino Owners!)

[Bilbo1967]

Originally Posted by orlok

Yes, I like Pointless too. I was happy to say at the start of the series that it was aptly named, but soon got drawn in and now watch it every chance I get.

I'm not going to have a guess at the quiz just yet - it's too late in the day, and I'm trying not to get too distracted from my writing (damn you MR), so I'll have a think again in the morning if one of our currently sleeping friends don't get there first.

I like Pointless and Only Connect too. Not embarassing to have a thing about Victoria Coren at all, although I've always thought she had massive ears I hate to mention it though, but she and David Mitchell announced their engagement last week.

The best quiz shows, in my opinion, are University Challenge and Mastermind. A couple of weeks ago, for the first time ever, I outscored one of the contestants on Mastermind on their specialist subject round.

Assuming that the strategy is correct the odds of walking away with 160 is one minus the odds of losing a 18/37** bet 5* times in a row. That should be 1- {5!/[0!x5!] x (18/37)^0x(19/37)^5 }= 1- (19/37)^5 = 1-.036 = 0.964

I assume that 5 is the smallest allowed bet. Otherwise the smallest bet each time would improve the odds.

*160-5x{1+2+4+ ...+2^n) = 5 for n = 4

**odds of hitting red each spin for a wheel with 18 red, 18 black, and one green.

[Bilbo1967]

Originally Posted by pdurrant

Yes, I believe that is indeed the best strategy. one point to you.

For two points, what are the odds of getting £160? (& no, you may not ignore the zero*!).



*European table. No double zero. (Greedy American Casino Owners!)

Would it just be 18/37 chance (i.e. the same as a single bet)?

Originally Posted by Hamlet53

Assuming that the strategy is correct the odds of walking away with 160 is one minus the odds of losing a 18/37** bet 5* times in a row. That should be 1- {5!/[0!x5!] x (18/37)^0x(19/37)^5 }= 1- (19/37)^5 = 1-.036 = 0.964

I assume that 5 is the smallest allowed bet. Otherwise the smallest bet each time would improve the odds.

*160-5x{1+2+4+ ...+2^n) = 5 for n = 4

**odds of hitting red each spin for a wheel with 18 red, 18 black, and one green.

Correcting slight error. Started with 155 not 160 so can make up to 5 bets exactly starting a 5 first bet and doubling each subsequent.

[Stitchawl]

Stitchawl

[Daithi]

Since you said European casino I'm going to assume we are using the French rules where there is only a single 0 on the wheel, and if you placed an even money bet and the ball lands in 0 then the "en prison" rule applies and the even money bets continue to ride.

So, if you bet everything in 1 shot your odds of winning are 50/50. However, you can improve these odds.

Let's assume that £1 is the minimum bet. Then you can make a bet of £3 to get to your £160+ goal. If you lose this bet then you'll need to increase your wager to cover your previous loss as well. You can actually make 8 losing bets before you won't have enough to cover all your losses with a single bet. The chances of losing all 8 bets is 1 in 256 (1/2^8), so you will win 99.6% (255/256) of the time. However, even if you lose all 8 bets you will still have a little money left over, so your odds of winning are actually a little better than even this.

If £5 is the minimum bet then you can only make 5 losing bets before you are broke. This is 1 in 32 (1/2^5), so you will win 96.875% (31/32) of the time.

[Bookpossum]

Originally Posted by Daithi

Since you said European casino I'm going to assume we are using the French rules where there is only a single 0 on the wheel, and if you placed an even money bet and the ball lands in 0 then the "en prison" rule applies and the even money bets continue to ride.

So, if you bet everything in 1 shot your odds of winning are 50/50. However, you can improve these odds.

Let's assume that £1 is the minimum bet. Then you can make a bet of £3 to get to your £160+ goal. If you lose this bet then you'll need to increase your wager to cover your previous loss as well. You can actually make 8 losing bets before you won't have enough to cover all your losses with a single bet. The chances of losing all 8 bets is 1 in 256 (1/2^8), so you will win 99.6% (255/256) of the time. However, even if you lose all 8 bets you will still have a little money left over, so your odds of winning are actually a little better than even this.

If £5 is the minimum bet then you can only make 5 losing bets before you are broke. This is 1 in 32 (1/2^5), so you will win 96.875% (31/32) of the time.

I don't believe it! Those places are geared so they win and the customers lose! But my grasp of mathematics is much too tenuous to cope with this one so I'm very impressed!

[Daithi]

Originally Posted by Bookpossum

I don't believe it! Those places are geared so they win and the customers lose! But my grasp of mathematics is much too tenuous to cope with this one so I'm very impressed!

Actually, I was a little off on how I stated the rule. When you are "en prison" you lose if the next non-zero roll is not the one you bet on, and you only win your wager back if it is the one you wagered on (you don't win the bet). Also, keep in mind that you are only increasing your odds to get to £160 by betting the minimum and doubling each time you lose, but at the expense of your entire bankroll. In the long run the house always has the advantage.

[orlok]

Originally Posted by Bilbo1967

Not embarassing to have a thing about Victoria Coren at all, although I've always thought she had massive ears I hate to mention it though, but she and David Mitchell announced their engagement last week.

What! THE David Mitchell, as in peep show??? Well at least she goes for brains rather than eye candy. One more point for her (and hope for me yet ).

I'm with Stitchy on the odds calculations on this one (even if I did get A Level Maths). The simple answer to me would be 18/37, as Bilbo has already mentioned. There are 37 numbers, including the zero, and the 50/50 bets only cover 18 of those numbers.

[pdurrant]

Hamlet53 has the answer I was looking for. I confess I didn't know that there was a special European rule for zero on otherwise 50/50 bets, I merely meant to indicate that the wheel had only a zero, not a zero and double zero.

The figures were chosen carefully to work nicely.

The best strategy in Roulette to win a certain sum is to bet that sum on red or black (or any of the other near-50/50 bets). This is because the odds are in the house's favour, so the more bets you make, the more likely you are to lose.

We need to win £5. So we must bet £5 and hope to win. If we don't win, we now need £10, so we must bet £10 and hope to win.

This doubling strategy is a classic roulette 'system', and works really well until you run out of money or hit the house limits.

In this particular case, we'll either get £160 or lose the lot. The first time we win, we'll get our £160, so the only way to lose is to always lose:

£155: bet £5 - lose
£150: bet £10 - lose
£140: bet £20 - lose
£120: bet £40 - lose
£80: bet £80 - lose
£0 = lost the lot!

So we win unless we lose five times in a row.
Odd of losing are 19/37. Odds of that happening five times in a row is (19/37)^5 = approx 0.0357.

So we have a (1-0.0357) chance of winning our £160: a little less than 0.9643.

In other words, just under 9643 times out of a 10,000 we'll get the £160 we were aiming for!

This sounds marvellous. Surely a way to beat the casinos?
The problem is that when we win, we win £5. When we lose, we lose £155.

9643 * £5 = £48,215
357 * £155 = £55,335

In the long run, we lose.

Over to Hamlet53 for the next question!

[Bilbo1967]

Originally Posted by orlok

What! THE David Mitchell, as in peep show??? Well at least she goes for brains rather than eye candy. One more point for her (and hope for me yet ).

Yes, that one.

Originally Posted by pdurrant

Hamlet53 has the answer I was looking for. I confess I didn't know that there was a special European rule for zero on otherwise 50/50 bets, I merely meant to indicate that the wheel had only a zero, not a zero and double zero.

- snip -

This sounds marvellous. Surely a way to beat the casinos?
The problem is that when we win, we win £5. When we lose, we lose £155.

9643 * £5 = £48,215
357 * £155 = £55,335

In the long run, we lose.

Over to Hamlet53 for the next question!

Yes as a way to earn £5 this is not good. In addition to the fact that if one attempts to employ such a strategy repeatedly one will lose money over the long term there is always the ~3.6% chance that one will just lose everything the first time. One could increase the odds of winning by starting with a larger stake and thus extending the number of times one can double down on previous bets, but the amount bet increases rapidly. For example to increase the odds of making that £5 to 99.9% one must start with at least £10,235 (prepare to make 11 bets, doubling each time, before winning that £5)..

In my opinion a better bet for obtaining that £5 is to go into the casino restroom and practice in front of a mirror a sympathetic pleas for £5 in order that you can afford that train ticket home (as an example). Then stand at the casino entrance an plead for £5 from everyone who enters or exits.


So I will have to think about a quiz question over the afternoon. If someone who has not had a chance at this in a long time, or never, feel free to jump in.