<p>"But it does increase your chance of winning one of them eventually, and the ratio is pretty close to double (and actually if you buy n tickets, it takes a fairly large n for the increase not to be close to a factor of n). "</p>
<p>no, it doesnt. not when you buy 1 ticket in one lottery, over and over again. Each time you start with the same odds. If you buy many tickets in one lottery, that will increase your chances of winning that particular lottery. But how many tickets you buy in one lottery has absolutely no bearing on you chances of winning future lotteries .</p>