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Old 09-27-2004, 07:49 AM   #1
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Math wiz help neede..

Ok I know how to calculate the Standard Deviation of say 10 given values....... But can some on etell mehow i can calculate the reverse...

Say i Have a standard devaition of 0.316 now I would like to generate say 10 values that give this deviation......

Thanx for any help...
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Old 09-27-2004, 08:09 AM   #2
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I doubt that it is possible; the same standard deviation could be obtained from an infinity of sets of ten numbers...you will never get the exact 10 that this deviation was used for. There might be a generalization about these infinite number of sets however... you need some more info vasanth.

I might be wrong, but right know I don't see a way - but I have statistics today and I just might ask my prof!
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Old 09-27-2004, 08:30 AM   #3
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well its fine as long as I get any 10 numbers within a given range that gives the same deviation...

I dont care what those numbers are as long as they satisfy the deviation..
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Old 09-27-2004, 08:35 AM   #4
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>>I dont care what those numbers are as long as they satisfy the deviation..<<

ahh, well that changes things a bit...when I get home today I'll try to work something out.
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Old 09-27-2004, 08:51 AM   #5
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Well, standard deviation is the square root of the variance, so I suppose you could plug in variables and try to solve for it? First off you'd have to find a mean.

(x-mean)'+(y-mean)'+(z-mean)'
--------------------------------------- = variance (' is "squared")
3

Trying to get 10 or so numbers crunced out of that is beyond me.

You do know that falsifying data is frowned upon, don't you?
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Old 09-27-2004, 09:12 AM   #6
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Quote:
Originally Posted by exluddite
You do know that falsifying data is frowned upon, don't you?
lol.. actually I need this data to simulate phone calls...(acually call holding time).. and the input given by the user is just the deviation and I need to do the rest...

Hope some one here can come up with a solution on how to calculate it..

thanx in advance..
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