Probability experts..

[anonymous-user]

This thread is brilliant

[anonymous-user]

cartel said:

one of those silly pubtime discussions

Which you took the wrong side in it would seem

[SC7]

It's like banging my head against a fking wall.

So 20 came up THREE TIMES INS FIVE LINES!?!? Shock horror!

There are only 49 numbers to choose from and by having 5 lines of 7 you have picked 35. Would you like them all to be different?

If I buy 7 lucky dips should I expect each of the 49 numbers to appear once?!

Christ on a bike.

[V8mate]

cartel said:

SC7 said:

The odds on two lucky dips being the same are exactly the same as picking the numbers that match the balls (14 million to 1?)

Euromillions is 76 million to 1.

But my argument was that the odds of randomly choosing two tickets exactly the same are less than wining the lottery because they must have algorithms in their distribution to ensure not many people get the same ticket?

I can not get my head around it being just as likely to have 2 identical lucky dips as winning the lottery. They must be slimmer?

Disclaimer: GCSE level maths only

Funny you should say that. As it is my entirely cynical belief that they issue duplicate lucky dip number selections like confetti. There have been a couple of times where an utterly disproportionate number of people have one a certain prize, including at least one jackpot and, though I have no actual proof, I believe that the spikes were caused by lucky dip winners.

[ewenm]

V8mate said:

cartel said:

SC7 said:

The odds on two lucky dips being the same are exactly the same as picking the numbers that match the balls (14 million to 1?)

Euromillions is 76 million to 1.

But my argument was that the odds of randomly choosing two tickets exactly the same are less than wining the lottery because they must have algorithms in their distribution to ensure not many people get the same ticket?

I can not get my head around it being just as likely to have 2 identical lucky dips as winning the lottery. They must be slimmer?

Disclaimer: GCSE level maths only

Funny you should say that. As it is my entirely cynical belief that they issue duplicate lucky dip number selections like confetti. There have been a couple of times where an utterly disproportionate number of people have one a certain prize, including at least one jackpot and, though I have no actual proof, I believe that the spikes were caused by lucky dip winners.

You'd expect spikes like that every so often if the allocation of number IS random - randomness generates anomalies and does not promote uniformity in a single example.

[SC7]

/\ Spot on.

Just like all the times nobody has won.

[V8mate]

ewenm said:

V8mate said:

cartel said:

SC7 said:

The odds on two lucky dips being the same are exactly the same as picking the numbers that match the balls (14 million to 1?)

Euromillions is 76 million to 1.

But my argument was that the odds of randomly choosing two tickets exactly the same are less than wining the lottery because they must have algorithms in their distribution to ensure not many people get the same ticket?

I can not get my head around it being just as likely to have 2 identical lucky dips as winning the lottery. They must be slimmer?

Disclaimer: GCSE level maths only

Funny you should say that. As it is my entirely cynical belief that they issue duplicate lucky dip number selections like confetti. There have been a couple of times where an utterly disproportionate number of people have one a certain prize, including at least one jackpot and, though I have no actual proof, I believe that the spikes were caused by lucky dip winners.

You'd expect spikes like that every so often if the allocation of number IS random - randomness generates anomalies and does not promote uniformity in a single example.

You are correct, but I maintain that they are deliberately re-issuing lucky dip numbers by the tens, if not more, of thousands.

[ewenm]

V8mate said:

ewenm said:

V8mate said:

cartel said:

SC7 said:

The odds on two lucky dips being the same are exactly the same as picking the numbers that match the balls (14 million to 1?)

Euromillions is 76 million to 1.

But my argument was that the odds of randomly choosing two tickets exactly the same are less than wining the lottery because they must have algorithms in their distribution to ensure not many people get the same ticket?

I can not get my head around it being just as likely to have 2 identical lucky dips as winning the lottery. They must be slimmer?

Disclaimer: GCSE level maths only

Funny you should say that. As it is my entirely cynical belief that they issue duplicate lucky dip number selections like confetti. There have been a couple of times where an utterly disproportionate number of people have one a certain prize, including at least one jackpot and, though I have no actual proof, I believe that the spikes were caused by lucky dip winners.

You'd expect spikes like that every so often if the allocation of number IS random - randomness generates anomalies and does not promote uniformity in a single example.

You are correct, but I maintain that they are deliberately re-issuing lucky dip numbers by the tens, if not more, of thousands.

Why would they bother? What's in it for Camelot (or whoever run it nowadays)? Surely it is better marketing for them to have a single big winner rather than lots of slightly disgruntled sharers. Keeps the hope alive!

[V8mate]

ewenm said:

V8mate said:

ewenm said:

V8mate said:

cartel said:

SC7 said:

The odds on two lucky dips being the same are exactly the same as picking the numbers that match the balls (14 million to 1?)

Euromillions is 76 million to 1.

But my argument was that the odds of randomly choosing two tickets exactly the same are less than wining the lottery because they must have algorithms in their distribution to ensure not many people get the same ticket?

I can not get my head around it being just as likely to have 2 identical lucky dips as winning the lottery. They must be slimmer?

Disclaimer: GCSE level maths only

Funny you should say that. As it is my entirely cynical belief that they issue duplicate lucky dip number selections like confetti. There have been a couple of times where an utterly disproportionate number of people have one a certain prize, including at least one jackpot and, though I have no actual proof, I believe that the spikes were caused by lucky dip winners.

You'd expect spikes like that every so often if the allocation of number IS random - randomness generates anomalies and does not promote uniformity in a single example.

You are correct, but I maintain that they are deliberately re-issuing lucky dip numbers by the tens, if not more, of thousands.

Why would they bother? What's in it for Camelot (or whoever run it nowadays)? Surely it is better marketing for them to have a single big winner rather than lots of slightly disgruntled sharers. Keeps the hope alive!

Just leave me and my conspiracy theory alone FFS!

[Some Gump]

OK, to clarify,

I have asked for 2 lucky dips twice.
Both times, the numbers went along the lines of:

7, 15, 20, 35, 47, 49
5, 8, 20, 35, 40, 49

As a result, I decided I was less likely to win a tenner, and now if both me and the missus play, we get seperate tickets. This could be coincidence, but if it is truly random, i figure the probability of this happening twice in a row is roughly... erm, hold on...

Matching 3 numbers is 1 in 57, so doing it twice is 1 in 3429?

I'm sure a lot of you don't believe me, but I'm really scratching my head as to why one would have motivation to make this up - hardly a "big man on t'interweb" topic (esp when you try to do maths in the thread)

[SC7]

Surely you can see there is just as much chance of that happening as there are any other numbers coming out?

Why not pick your own? You're just as likely to win a tenner.

In fact, if you have 3 numbers the same on two lines, there's just as much chance you'll win £20.

[Jonnas]

Surely the chance of two lucky dips the same on the same ticket is 196 million to one?

[V8mate]

Jonnas said:

Surely the chance of two lucky dips the same on the same ticket is 196 million to one?

I would suggest that the chances of that are zero - they'd never be that stupid.

[SC7]

V8mate said:

Jonnas said:

Surely the chance of two lucky dips the same on the same ticket is 196 million to one?

I would suggest that the chances of that are zero - they'd never be that stupid.

Tin foil hat on?

[cartel]

Nyphur said:

cartel said:

one of those silly pubtime discussions

Which you took the wrong side in it would seem

Well I am ALWAYS correct after 2 pints

[cartel]

SC7 said:

It's like banging my head against a fking wall.

So 20 came up THREE TIMES INS FIVE LINES!?!? Shock horror!

I think you are not understanding me

This happens consistently. I mean, nearly every time. There is always the odd number which creeps into each line and pisses me off

I know it does not affect your chances of winning, would just prefer for it to be more random.

01 comes up too much for my liking too

Edited by cartel on Saturday 4th December 19:17

[Huff]

Crikey, time to dust off a long-forgotten A-level. My take:

The lottery uses 49 balls. You have 6 picks, plus the bonus ball. Everyone is given the bonus, so your chance of picking the first winning ball (in any order) is 1/48. So the expectation of winning based on picking 6balls from 48 unique possibilties is C(n,k) = C(48, 6) = 48!/(6! * 42!) = 1 in 12.2million. Ish (I've had a drink, and I've never played the Lotto...)

BUT

The chances of having all-unique numbers in your total set depends dramatically on the number of picks of sets of six.

Picking 2 sets of 6numbers from 49 the chance is 1/49 +1/48 +.... 1/37= 1 in 3.2. Yes, roughly a 1 in 3 chance! BUT your chance of winning is still only roughly 2 in 12million.

Pick 3 sets and you add ...+1/35 + 1/34....+1/31 which drags the odds down to 1 in 2.19 - nearly 50:50.

Beyond that, the addition of larger chances (from 1/30 down to 1/24 on the third blind draw) makes duplication is a virtual certainty - exactly like the birthdays paradox mentioned.

- So even if the picks are truly random, take three luck-dips and you are nearly evens on having at least one number repeat even though practically speaking, you are no more likely to win outright. Grab a calculator and drive yourself mad from there.



Yes, the lottery is a way of taxing those who can't do maths

[cartel]

Huff said:

Yes, the lottery is a way of taxing those who can't do maths

Or those who view it as a fun utility for potential New York apartment and Veyron

Come to think of it.. I am pretty rubbish at maths

[Huff]

PS. carrying -on my line of madness, a quick check suggests getting the same number 3 times in 5 sets of 6 picks... much less than a 1:1 chance, around/just above 2:1-on in fact. So yes, you *should* expect such things - it would be odd if it did not happen!

Your odds of winning overall still languish around the 1 in 2.7million mark though

Edited by Huff on Saturday 4th December 20:18

[zac510]

There is a huge element of human nature that wants to see patterns. For example you might pay more attention to a ticket in which 20 appears in 3 out of 5 lines (which is completely within the bounds of random) whereas dismiss a ticket that doesn't contain a comparable pattern. The ticket with the pattern will come back to your attention and you'll convince yourself into believing it happens more often because it is human nature to want to see the pattern.

Also patterns and randomness are not mutually exclusive, at least in my opinion.

edit for grammar

Edited by zac510 on Saturday 4th December 20:42