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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 21, 2011 4:37 AM

On Wed, 20 Jul 2011, checker wrote:
> On Jul 19, 9:58 pm, William Elliot <ma...@rdrop.remove.com> wrote:
>> 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

>>
>>> 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.

>>
>> 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
>>

Such there are other statistical measures such as

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

it'd help were you to learn about them.

> Thanks for taking the time to reply. I realize the problem is poorly
> stated and I guess that's one of the things for which I'm
> fishing...how to formally state the problem...along with the
> appropriate branch of math to research.
>

"..." is a poor way to state any thought.

"... for which I'm fishing is how to formally ..."
shows the correct usage of "..." as words omitted
and how to write your thought.

I suggest you look into statistics.

> The measure you've provided works for series of equal lengths. To
> apply such to my problem, which allows deletion (or addition) of one
> or more elements of the series, I would need to walk all possible
> combinations that delete elements of a longer series against the
> shorter series. I was hoping for a less iterative solution.
>

Since all the entries are positive, you could try putting a zero in the
blank spaces. As it's an interesting problem, I've posted the problem
here at sci.math under the title of "Statistical comparison". We'll see if
it gets the attention of somebody who actually knows some statistics (which
I don't).

> Regards,
>
> 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