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#1 Re: Help Me ! » Permutations » 2014-10-23 09:53:30
Hi
Just to let you know, Ive rechecked my figures, and when recalculating the extra permutations for the sort order of the sets, I'd allocated the wrong pattern to a couple of them and that overstated the permutations.
Ive now got the listing to support 11628 permutations.
Thanks very much for your help.
#2 Re: Help Me ! » Permutations » 2014-10-23 07:30:09
I tried with multiple use of the web sites' permutation calculator, and I got 11778 ways, so I must have made a mistake somewhere. I will have to recheck.
Thanks again for your help.
#3 Re: Help Me ! » Permutations » 2014-10-23 05:16:41
Thats great! Thank you very much!
Can you explain how you did it so I can replicate, and get a listing of the groups, as Is provided in the permutations calculator ?
#4 Re: Help Me ! » Permutations » 2014-10-23 01:13:50
Hello - and thanks for your help.
Yes, they are two valid permutations. The user is trying to size how many possible sets of permutations he needs to allow for, and any permutation that results in a different total valuation of the assets is to be counted.
In the example, the criteria is true because Asset No:6 x 0.75 (set 1) will be different from Asset No:2 x 0.75 (set 2), giving two different totals.
#5 Re: Help Me ! » Permutations » 2014-10-22 07:50:34
Hello bobbym
Im sorry if I didn't make things clear.
1. The permutations will be selected from 18 numbers ranging from 0.05 to 0.90 at intervals of 0.05 (so... 0.05, 0.10, 0.15 .... etc).
2. These numbers represent weighting factors that can be applied to six groups of assets, and we need to establish how many different sets of six that we can pull from the 18.
3. Its OK for the same weighting factor to be used on multiple asset groups, as long as the six factors total 1 (one) which is a requirement for all valid sets.
4. Examples:
Asset 1 Asset 2 Asset 3 Asset 4 Asset 5 Asset 6
0.05 0.05 0.05 0.05 0.05 0.75 OK
0.05 0.75 0.05 0.05 0.05 0.05 OK
0.10 0.20 0.05 0.10 0.40 0.15 OK
0.10 0.20 0.30 0.40 0.50 0.60 Not OK because sum is > 1 (2.10).
5. So the question is: How many sets of 6 can be obtained from the 18 numbers, where the sum of the 6 vaues is equal to 1 ?
Proviso: Although one of the 18 factors can be used up to 5 times in a set of 6, it would not be valid to make another permutation by exchanging one of these for another of the same value as this would have no affect on any weight calculation. In other words 0.05 x Asset 5 will be the same no matter which instance of 0.05 is used.
In contrast, the change betwwen the first two examples above is a different permutation because 0.75 x Asset 6 will be different from 0.75 x Asset 2.
Hope that answers your questions
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