2007-05-27 02:53:43 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
If you are asking about the differences between 2 sets of data -- for example, "Before and After" data. One set of date represents measurements performed on items. The second set represents measurements ON THE SAME items after some procedure is performed on these items. Then the differences between the before data and the after data is recorded and the standard deviation is found on the DIFFERENCES.
Then the SD= sqrt((n(SS)-(sum of the differences)^2)/(n(n-1)))
Where SS is the sum of the squares of each difference. n is the number of differences.
2007-05-27 07:57:23 · answer #1 · answered by cvandy2 6 · 0⤊ 0⤋
My recommendation is to find a calculator with the SD function..examine your data set carefully, work backwards if you have to.
/been years since college statistics
2007-05-27 09:58:54 · answer #2 · answered by Anonymous · 0⤊ 0⤋
learn standart deviation formula
search google or check your book
2007-05-27 10:13:45 · answer #3 · answered by iyiogrenci 6 · 0⤊ 0⤋