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buddyboy
10-25-2004, 01:19 AM
Please help me to answer this question ....(see attachment, the answer is shown)

:(

dustino
10-25-2004, 06:30 AM
They're only trying to confuse you with the listing of the Standard Deviation. The Arithmetic Mean Rating is nothing more than the Average. They want the average closest to '0', which we can easily find by looking at the middle column, which gives us the summation of all 30 items in the set. The largest number is 35, and 35 / 30 = 1.17. This isn't listed and seems high, so let's try the smallest value.

The smallest number is 2 (don't forget to look at this in terms of the absolute value, -33 has the same value as 33 as far as its distance from 0), and 2 / 30 = .067, the given answer.

buddyboy
10-25-2004, 07:03 AM
Cool!!! I got it now. Thank you very much dustino!!!!!!!!!!

Edstroyer
10-28-2004, 06:36 AM
well, the smallest average is the one closest to zero , which means that the perfect answer would be: 15 people voting -1 ,and the other 15 voting +1, which would make an average of zero .

this is a picture i imagined :

15 people (red team ) <--> 15 people (blue team)

-15 votes <--> +15 votes ===> average is (-15 + 15 )/30 = 0

but since lowest sum closest to zero is +2 , then two members from blue team voted +2 each ... adding an extra point each.

so finally average the votes of both teams you get +2/30 = (2/3)/10= 0.0666~

hope i didn't confuse things.... :whistle: