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dminder
Aug 22nd, 2008, 03:08 PM
Not sure if anybody can help with this or not.

The problem is that I have a 10-digit string and there are only 8 possible characters for any one column (a, 1, x, ?, o, U, 7, n, !, D).

I have 1000 iterations of this string to base history off of.

What calculation(s) would I use to figure out the probability of 'x' showing up in column 2 of this string (or any column for that matter) on the next iteration?

No, this is not homework and no I am not a math wiz. This is a pet project I am working on and am not even sure what this would be called.... :o

Thanks,

D

jemidiah
Aug 22nd, 2008, 03:28 PM
What do you mean by "iterations" exactly?

Fizziii
Aug 22nd, 2008, 04:47 PM
If there are no restrictions to letters repeating... wouldn't it be 1 in 8?

NickThissen
Aug 22nd, 2008, 05:20 PM
I think you need to give us some more information. Again, what do you mean by iterations, and what do you mean with "to base history off of"..?

If I have to guess, I think you cannot have two identical strings maybe? And you already have 1000 different strings, and want to calculate the possibility of an 'x' on a certain position on the 1001th string (which should again not be identical to any of the other 1000 strings)..?

jemidiah
Aug 22nd, 2008, 11:32 PM
If the history directly influences the content of the 1001st string, the "iteration" operation should somehow use the history you have to create the next string in a sequence of strings. That is, you should be able to make a function with this signature: "NextIter(StrHistory() As String) As String". If this is the case, tell us how this function would work.

If the history does not directly influence the content of the 1001st string, tell us how the history reveals any information about the content of the next string. That is, if you have (or can make) a generating function like the one above that takes different arguments, tell us what the point of having the history is.


...it all depends on exactly what you mean by "iteration" and what you're using to generate the 1001st string. Without that, we can only take shots in the dark at the probabilities you want.

dminder
Aug 25th, 2008, 06:53 AM
It is kind of a guessing game. I made a function that spits out the string with only the characters mentioned. The goal is to figure out a way to calculate the probability of character 'x' falling into the given column on each iteration.

The history (iterations) is what my brain said I would need to help figure that out. I know that if I only have 10 characters and 10 slots then the basic probability would be 1 in 10 (again guessing, calculations not my strong suite!). However, if I also throw in there that the characters may repeat and that the string is generated at random, then that throws the whole thing awry and I am curious what kind of formula would be needed to calculate.

Does that help to clarify?

Thanks!

D

jemidiah
Aug 25th, 2008, 08:51 PM
How is this different from guessing? Again, how is the next iteration generated?

If we can have that info we'll probably be able to answer your original question.

Shaggy Hiker
Sep 1st, 2008, 10:20 AM
If the string is generated at random, as you say, such that the next string is not related to any previous string, and the columns are all generated independently from the eight characters, then the probability of character C showing up in column L on any iteration is 1 in 8. If there are ten characters, then the probability of C showing up somewhere in the string is 10 in 8, because over the long run, about 20% of the strings will have C twice (while some will have C 0 times, some will have C three times, four times, etc.)