Import["/Users/doc/Documents/Work/Probability2/lotto.csv"];

First, import the data.  In this case, the winning Little Lotto numbers from the last three months (July, August, and September of 2009). This data is then adjusted for Mathematica.

lotto = Flatten[%]

tally =Tally[lotto]

After the numbers are imported, we can "tally" them. So 8 appears 12 times, 16 appears 9 times, and so on. This can be plotted as shown below.

ListPlot[tally,Filling->Axis]

Sort[tally,#1[[2]]<#2[[2]]&]

We can sort this list.  So 36 has the most appearances and 30 has only 2 appearances.  Also, from the list plot above, the number 40 has not appeared in the last 3 months.

Maybe it's time for 40 to appear. Maybe all the numbers that have few occurences should and will catch up.  So you may pick 11-21-27-29-40. This is the "it's about time" strategy.

However, if some numbers are hot, they might appear again.  So you can pick 10-18-26-17-36. This is the "hot streak" strategy.

You can mix these up and pick 17-21-26-36-40; the "hot and cold" strategy.

The "hot-cool-cold" strategy would include the other numbers in the middle.  So you may try 6-17-19-36-40.

This does not guarantee a win.  However, you are a Math Major, and so, start thinking (if not acting) like one.

You can do more here.  For instance, if you believe in the "hot" numbers, how do you distinguish between 17, 26, and 18 (all these have 15 occurences)? You can see when they appear in the list.

Position[lotto,17]

Position[lotto,26]

Position[lotto,18]

So 18 appeared in the 363rd position and before that it showed up in spot number 330.  Apparently, it is not as hot as 17 and 26, since they have appeared more often more recently.