1. A student was asked to evaluate the mean and standard deviation for following sample of n = 5
81, 87, 89, 86, & 87. To simplify arithmetic, the student first subtracted 80 points from each score to obtain the new sample consisting of 1, 7, 9, 6, & 7. The mean and standard deviation for new sample were then evaluated to be M = 6 and s = 3. What are the values of mean M and the standard deviation s for original sample? Hint:What takes place to the mean when you subtract the constant from each observation?
2. There're two different formulas or methods which can be employed to compute SS.
- Under what circumstance is the definitional formula easy to use? Hint: Refer to the text
- Under what circumstance is the computational formula easy to use? Hint: Refer to the text