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Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by neom on Wednesday December 02, 2020 @12:26PM (#25278757)
I'm so curious what the chances of this happening are.
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by mattnewton on Wednesday December 02, 2020 @12:58PM (#25279172)
If it's done properly, it's the same as any other sequence, right?

I don't know how many balls they have and whether there is replacement to tell you the actual number, but there shouldn't be anything special about this one among all the other possible sequences, except that it's more likely to be guessed.

Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by fortran77 on Wednesday December 02, 2020 @03:28PM (#25281125)
Actually, it's more!

1,2,3,4,5,6 and 10,11,12,13,14,15 and even 2,4,6,8,10,12 would have had the same amount of attention and scruitny.

So "what are the odds that a sequence of numbers would come out that would look 'funny' to many people" is now not one out of n, it's several hundred out of n.

Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by bryanrasmussen on Wednesday December 02, 2020 @03:52PM (#25281453)
I was thinking what's the odds that any number drawn will have a special relationship to the number drawn before, where the degree of specialness is determined by how many people hearing the number think "huh, that's weird"
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by oh_sigh on Wednesday December 02, 2020 @02:01PM (#25280018)
Yes, but there are vastly more non-incrementing sequences than incrementing sequences.
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by jerf on Wednesday December 02, 2020 @01:12PM (#25279352)
Many repliers are computing the probability of this exact draw, but probably a more relevant consideration of "this" is "the odds of a 'suspiciously regular' combination being drawn". The probability of one of those occurring is (the number of such sequences you name):42,375,200, or that number over 42,375,200.

There is some inherent fuzziness in what you consider a "suspicious sequence", obviously. If you stick to entire sequences you don't get very many; however, if you consider "1 2 3 4 5" in the original numbers to be suspicious regardless of the bonus ball draw, then the number of such sequences starts going up fairly quickly. (Include things like [1,3,5,7,9], [2,4,6,8,10], [3,6,9,12,15], etc.)

It's pretty easy to get up to a couple thousand "suspicious sequences". For the sake of roundness and being a bit conservative, let's say there are 423 "suspicious sequences", in which case the odds of hitting one are roughly 1 in 100,000. You may choose to add another order of magnitude of "suspicious sequences" pretty easily, in which case it goes to 1 in 10,000. Given the number of draws done for this sort of lottery (dozens or hundreds a day, I'd guess), it's inevitable that sooner or later one would be hit on lotteries of this size.

Some of the challenge in weighting the number of sequences is they aren't all equally "suspicious". [1,2,3,4,5] is what most people would consider a "dead giveaway" (right or wrong), whereas [1,2,4,8,16,32] would probably bother fewer people. Some people might still find even [1,2,3,4,18,bonus 6] suspicious ("look how 'close' it was to 12345!"). So there's just some intrinsic fuzziness to the answer of how likely this is.

Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by VBprogrammer on Wednesday December 02, 2020 @12:56PM (#25279147)
The same as any other combination of numbers. It's just harder to wrap your head around.
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by redkoala on Wednesday December 02, 2020 @01:04PM (#25279248)
It’s the same likelihood to draw the numbers, however more people are likely to buy that sequence of numbers as it is a very common sequence that people think of.
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by jcranmer on Wednesday December 02, 2020 @12:56PM (#25279152)
According to the article (assuming you're looking at this particular sequence):

> The chances of winning South Africa's PowerBall lottery are one in 42,375,200

Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by hervature on Wednesday December 02, 2020 @01:03PM (#25279236)
Yes, as others pointed out, this particular sequence is the same as every other sequence. Or, the one person who said 100% is referring to the probability of something that already happened.

To give you a more charitable interpretation, the South African lottery Powerball can be 1-20 so there are 20 straights possible so 20 in 42,375,200. Or roughly 1 in 2,000,000 or roughly 40,000 years of weekly draws to see a straight.

Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by strombofulous on Wednesday December 02, 2020 @01:08PM (#25279298)
I think there are only 16 straights possible since you can't start with 17, 18, 19, or 20
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by hervature on Wednesday December 02, 2020 @01:29PM (#25279588)
Yes, you're right. In this case, the Powerball comes last. So increasing straights can't end with 1, 2, 3, 4, or 5. However, you could have wrap around straights. So 15 or 20 depending if you allow the wraparound.
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by mdavidn on Wednesday December 02, 2020 @01:16PM (#25279416)
It depends on how many samples. The odds that this specific drawing would yield this result should be one in 42 million, but the odds that a lottery somewhere would yield this result in our lifetime is substantially greater.
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by colechristensen on Wednesday December 02, 2020 @12:59PM (#25279187)
The same as any other combination, as quoted in the article, 1 in 42 million.
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by thehermit on Wednesday December 02, 2020 @01:01PM (#25279199)
The question most people are probably thinking of is "What are the chances of any sequence of numbers being drawn?", not just this specific one in the article.
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by ptaipale on Wednesday December 02, 2020 @01:03PM (#25279243)
And that is, literally, quite close to one in a million.
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by madcaptenor on Wednesday December 02, 2020 @01:12PM (#25279351)
Actually no, because this lottery picks five balls from a pool of 50 and then one ball from a pool of 20. So there are only 15 possibilities where the whole draw is six consecutive numbers (from 1-2-3-4-5/6 to 15-16-17-18-19/20).
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by greenshackle2 on Wednesday December 02, 2020 @01:27PM (#25279556)
Does draw order matter in this lottery? Cause if not it's a lot more likely.
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by denni9th on Wednesday December 02, 2020 @03:22PM (#25281055)
No, in fact the numbers were not drawn sequentially but arranged in order after. The only exception is the powerball, the 10 in this case, which always is last in the draw and positioned last in the final numbers.

This can be seen in the official announcement: https://youtu.be/11RN1pEnrTo

Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by throwdour on Wednesday December 02, 2020 @03:35PM (#25281220)
Isn't the real question "what are the odds of the lottery being random if this suspicious sequence comes up so soon"? I.e. given a specific sequence, how many weeks should you expect to wait before you see it? In the extreme if you would expect to see 1,2,3,4,5,6 after 500,000 weeks, but you see it in the first week, then probably the lottery is not random, right?
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by jon-wood on Wednesday December 02, 2020 @12:56PM (#25279149)
Exactly the same as for any other sequence of numbers.
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by ptaipale on Wednesday December 02, 2020 @01:02PM (#25279220)
Which is 1 : 42,375,200.

However, the probability of ending up with a sequence like this is still quite low - probability of coming up with six consecutive numbers is 40 : 42,375,200 i.e. less than one in a million.

Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by ptaipale on Thursday December 03, 2020 @01:08PM (#25292238)
Correction: as pointed out, the sixth ball is picked from range 1-20, which more than halves the probability to less than one in 2 million.
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by disown on Wednesday December 02, 2020 @12:56PM (#25279150)
100%
Re:South Africa's lottery probed as 5, 6, 7, 8, 9 and 10 drawn by singularity2001 on Wednesday December 02, 2020 @01:14PM (#25279385)
Up to which resolution is a fundamentally deterministic world ruled out?