I did a 3rd year Uni project on this a few years ago. It downloaded and analysed the number of winners (3, 4, 5 or 6 numbers) and reverse engineered the number choice distributions.
7, 13, 31, and numbers on the edge of the choice-sheet were all more likely choices than the rest.
The conclusion was that if you played for a very long time, you were likely to break even.
That was before the lucky dip started though.