This one is fairly simple.
Using a random number generator, generate 100,000 sets of four numbers. Email these to 100,000 different people, accompanied by the message "These are four of the five numbers which will be drawn in next week's lottery." Keep track of which recipients were sent which numbers.
Assuming that at least one of those sets of four numbers happens to be correct, email that same person (or those same persons) the next week, again with four randomly-chosen numbers; and offer to send them the 5th number for a fee.-- MaxwellBuchanan, Apr 03 2016 Halfbakery: Become Astoundingly Rich Become Astoundingly RichSee [imaginality]'s comment about millions of email recipients and stock-market predictions [zen_tom, Apr 04 2016] Darren Brown's television version of this, with a smaller number of initial variables https://en.wikipedi...e_System_.282008.29 [calum, Apr 04 2016] Be a prophet, guaranteed! http://www.halfbake...et_2c_20guaranteed! [Voice, Apr 05 2016] .....and they offer to pay you double the amount out of their anticipated winnings-- xenzag, Apr 03 2016 But who would possibly trust someone who would fall for such a scam?-- MaxwellBuchanan, Apr 03 2016 Actually, thinking about it, what's needed is a website which displays a set of random numbers that is different for each IP address viewing the page (but consistent between views, for any one IP address).-- MaxwellBuchanan, Apr 03 2016 I think I've heard about this being done with football scores. Send out a bunch of predictions and keep track of who received the right ones then charge them for next week's scores. If you're sending out enough, you can even send out a second week of scores so a very small number of people think you're right every week.-- doctorremulac3, Apr 03 2016 It is similar to a common stock market scam run by stockbroker salesmen. Tell 64 people where any volatile stock is headed. "Just watch it. Ya don't gotta buy nuttin. "
32 up 32 down
then 16 up and 16 down
then 8 up and 8 down
and finally 4 up and 4 down.
Then call the ones you've guessed right on 4 times in a row. They think you really know and put in big money and their friends money into whatever cockamamie stock you are flogging.-- popbottle, Apr 03 2016 If you knew 4 of the winning numbers, couldn't you just buy a ticket for each of the remaining options?
Also, you would have to be really stupid to fall for this scam. If someone knew the winning numbers to a lottery, why would they possibly need a stranger to buy the winning ticket? If the numbers where arrived through clairvoyance, the person could get buy the ticket themselves; if the numbers where arrived at by nefarious means (and didn't want to be directly associated with the win), the person would find a trustworthy friend.-- xaviergisz, Apr 04 2016 //you would have to be really stupid to fall for this scam//
Damn - I suppose you're right. Well, that still leaves 98.3% of the population.-- MaxwellBuchanan, Apr 04 2016 I'm pretty sure this has been half-baked before. At least once.-- pertinax, Apr 04 2016 There's prior annotation discussion - I've linked an idea I think rather neatly dovetails with this one in an upside-down sort of way - [imaginality] mentions therin something along similar lines, but regards stock market predictions (rather than lottery numbers)
The effect is more pronounced when you can show repeated success over a period of time - but that's tricky with lottery numbers as the field of possibility thins rather rapidly due to the number of starting conditions you'd have to cover.-- zen_tom, Apr 04 2016 Just predict two of the required numbers. Then you don't even need to randomly generate them, just work in multiples of every combination. There are 10 successfully predictions per combination cycle. Also, this makes it more likely that the mark will pay to get the remaining numbers rather than buying the four you provide plus a random fifth ball, for a smaller win.
Or just predict a single ball. Then the odds are big enough that you could iterate on the fraction of successful predictions.-- Loris, Apr 05 2016 // Also, you would have to be really stupid to fall for this scam. //
The Nigerian email scam deliberately uses poor spelling and grammar so that smart people will realize it's a scam and self-select out, leaving only the stupid recipients for the scammers to work with.-- notexactly, Apr 07 2016 The scammer is playing a lottery that his one recipient will even read one email let alone two a week apart.-- guncandy, Apr 09 2016 random, halfbakery