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Lottery DataBase Analysis - 03 (_.reduce)


California Lucky for Life (832)
Prizes                     Odds 1 in     Total # of Winners
$3,250,000.00         2400000                          17
$5,000.00                1200000                          34
$1,000.00                  400000                        102
$500.00                       12000                      3400
$100.00                           645                    63240
$40.00                             350                  116620
$20.00                               53                  765000
$15.00                               40                1020000
$10.00                               20                2040000
$5.00                                 11                3570000
Ticket ($5)                         10                4080000

There are more data points available on the lottery website, so I grabbed the Total # of Winners.


var numberEachPrize = [17,34, 102, 3400, 63240, 116620, 765000, 1020000, 2040000, 3570000, 4080000];
document.getElementById('outputOne').innerHTML = _.map(numberEachPrize, function(n){return ' ' + n;});

Yields:
Nada Yet



Multiplying the Individual Prize Odds by the Number of Each Prize should yield a Total Number of Tickets.

outputTwo = 2400000 * 17;
Yields:
Nada Yet
Which can be eyeballed against the free ticket odds (10 x 4080000)
So, that looks good.



And then, to find the overall odds, adding up the Total Number of All Prizes Available would be a good next step. So,

var outputThree = _.reduce(numberEachPrize, function(memo, num){return memo + num;}, 0);

With Total Number of All Prizes equaling =
Nada Yet


Overall odds (if I know any probability at all) should be given by:   #Wins / #Tries
var outputFour = outputTwo / outputThree;

Yields an overall win rate of 1 in
Nada Yet
which compares favorably to odds listed on ticket (1:3.50)


To double check, back out the winning tickets.
var outputFive = outputTwo / (outputThree - 4080000);
And we have odds to win any prize:
Nada Yet
which once again is spot on to the value on the ticket (1:5.38)

Even more so, since the rounding occurs as one might like (in either direction, per standard rules).
So, throw out the previous web page (don't know what I was thinking) and we'll use the logic on this page from here on out.



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© Copyright 2013 Brett Paufler



Please Note: I am an idiot.  No seriously.  The odds of my gambling odds calculations being correct are likely on par with my odds of ever winning.  You have been warned.