Review Questions: Answer the following questions in detail.
1. Explain the notions of mathematical differences, managerially important differences, and statistical significance. Can results be statistically significant and yet lack managerial importance. Explain your
2. Describe the steps in the procedure for testing hypotheses. Discuss the difference between a null hypothesis and an alternative hypothesis.
3. What purpose does a scatter diagram serve?
4. The following ANOVA summary data are the result of a regression with sales per year (dependent variable)as a function of promotion expenditures per year (independent variable) for a toy company.
F = MSA = 34,276
The degrees of freedom are 1 for the numerator and 19 for the denominator. Is the relationship statistically significant at ” = .05? Comment on your answer.
5. The following three random samples are taken from three normal populations with respective means ?1?1, ?2?2, and ?3?3, and the same variance ?2.?2.
Sample 1Sample 2Sample 32302513725 13
Find the combined sample size n.
Find the combined sample mean x??.x-.
Find the sample mean for each of the three samples.
Find the sample variance for each of the three samples.
Here are the formulas to help you solve:
The combined sample size:
n=n1+n2+?? ? ??+nKn=n1+n2+?· · ·?+nK
The mean of the combined sample of all n observations:
x??=?xn=n1x??1+n2x??2+?? ? ??+nKx??Knx-=?xn=n1x-1+n2x-2+?· · ·?+nKx-Kn
The mean square for treatment:
MST=n1(x??1?x??)2+n2(x??2?x??)2+?? ? ??+nK(x??K?x??)2K?1MST=n1(x-1?x-)2+n2(x-2?x-)2+?· · ·?+nK(x-K?x-)2K?1
The mean square for error:
MSE=(n1?1)s21+(n2?1)s22+?? ? ??+(nK?1)s2Kn?K
Deliverable length 3-5 body page in APA format with the incorporation and citation of reference material. Show formula calculations.