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Topic: associating sequences of numbers
Replies: 5   Last Post: Jul 21, 2011 6:18 PM

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 William Elliot Posts: 1,948 Registered: 5/30/08
Re: associating sequences of numbers
Posted: Jul 20, 2011 12:58 AM

On Tue, 19 Jul 2011, checker wrote:

> I'd like some guidance on how to associate series of numbers.
> If I have several series of whole numbers
>
> A = 2 4 6 1 8 4 4 5 1
> B = 1 1 8 4 4 7 3
> C = 8 3 2 2 5 6 4 4 2 5
>
> That are represented in an array as
>
> Set1 =
> 2 4 6 1 8 4 4 5 1 -
> 1 1 8 4 4 7 3 - - -
> 8 3 2 2 5 6 4 4 2 5
>
> And I'm presented a second array like
>
> Set2 =
> 2 4 6 1 8 4 4 5 1 -
> 1 1 8 4 5 7 3 - - -
> 8 3 2 4 4 2 5 - - -
> 5 8 8 9 3 2 3 3 1 3
>
> where
> Set2(2,5) changed to 5
> Set2(3,4:6) removed

Huh? Does that mean anything?

> I'd like an approach that would associate
> Set1 row1 with Set2 row 1 with high probability
> Set1 row2 with Set2 row 2 with high probability
> Set1 row3 with Set2 row 3 with high probability
> and all other associations (say Set1 row 1 with Set2 row 2) with low
> probability.
>
> The important information is contained in a row and is represented by
> the value and the sequence. That is, 1 2 3 would be poorly associated
> with 3 2 1. The row location in the array is not important. That is,
> the first row in the first array could be duplicated in the 2nd row of
> the second array. In this case, the method would associated the first
> row of the first array with the second row of the second array with high
> likelihood.

Confusing in view of the previous paragraph.

> It looks like a stats problem, but the importance of the sequence (the
> relation of one number to it's neighbor) is undermining my meager
> understanding.

If a1, a2,.. a_n and b1, b2,.. b_n are two data sets,
one measure of similitude is

(sum(j=1,n) (aj - bj)^2) / n

>
> Chris
>

Date Subject Author
7/19/11 checker
7/20/11 William Elliot
7/20/11 checker
7/21/11 William Elliot
7/21/11 Ken.Pledger@vuw.ac.nz
7/21/11 checker