BUMP: those downvoting. It's a serious question. The article doesn't explain the student's methods. I really don't know what they did to game the system. Is it well known?
Ok, found the summary on Wikipedia [0], which matched my recollection from a TV news magazine report from a few years ago when this came out.
When the jackpot reached a certain point, they'd increase the payout on the lower tier prizes (match 5, 4, 3) from ($4000, $150, $5) to something more significant.
Instead of needing to match all 6 numbers (range 1..46), you could get a good return by only trying to match a smaller set. I guess they worked out a good distribution of tickets to purchase that covered a large percentage of those possibilities. They were purchasing 300k tickets to guarantee their 15-20% ROI.
I think the tone of the article is because the lottery officials did nothing to stop the practice.
"The inspector general’s report claims that lottery officials actually bent rules to allow the group to buy hundreds of thousands of the $2 tickets, because doing so increased revenues and made the lottery even more successful."
