August 15th, 2010 at 4:51:39 PM
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Looking at this description:I'm struggling to understand the mathematics behind the table "Rows Covered by Number of Marks" at the bottom.
Currently I'm using a hypergeometic distibution for 1 line P(X=5) to calculate the probability that, when I have m marks, I have a whole line. I then multiply this by 3. This works fine till m=10. Now the probability that you could have 2 lines comes in. I'm calculating the probability for 2 lines in a similar way (different distribution) by finding P(X=10). Now how do I calculate the probability that there are no lines when m=10 and above? If i go on calculating individual lines, of course, I get probabilities summing to more than 1 for all instances.
Currently I'm using a hypergeometic distibution for 1 line P(X=5) to calculate the probability that, when I have m marks, I have a whole line. I then multiply this by 3. This works fine till m=10. Now the probability that you could have 2 lines comes in. I'm calculating the probability for 2 lines in a similar way (different distribution) by finding P(X=10). Now how do I calculate the probability that there are no lines when m=10 and above? If i go on calculating individual lines, of course, I get probabilities summing to more than 1 for all instances.