1. Consider the following one-way ANOVA table to compare the means of 4 populations.
a. Fill in the numbers for all the missing cells:
Source Degree of
Freedom
Sum of
Square
Mean
Square
F Test
Statistic
p-value
Factor 136.5 0.4346
Error
Total 15 692
b. Multiple Choice: Based on the above ANOVA table, I can conclude the following
about the means of the 4 populations
i. The means of the four populations could be the same
ii. At least one of the 4 means is different from the rest and Tukey’s HSD is
need to determine which mean(s) differ
iii. There is not enough information to make any conclusion about the
means of the four populations
2. A major federal agency in Washington, D.C. regularly conducts classes in PL/1, a
computer programming language used in the programs written within the agency. One
week, the course was taught by an individual associated with an outside consulting firm.
The following week, a similar course was taught by a member of the computer staff
agency obtaining the following results on the satisfaction of the students in the course
(maximum score of 64). The instructors want to know if the data presents sufficient
evidence to indicate a difference in student satisfaction between the two teachers.
Taught by
outsider
Taught by Staff
Member
38 46
42 33
53 38
37 60
36 58
48 52
47 44
47 45
44 51
Use JMP to analyze this data and then answer the following questions:
a. What is the mean satisfaction score of the students who took the course with an outside
teacher? The mean score of the Staff Member students?
b. Write out the null and alternative hypotheses needed to analyze this data. Using the
appropriate test, does the data suggest that there is a difference in the mean
satisfaction scores between the two teachers? Find and list the appropriate p-value in
the JMP output and draw your conclusion (write in sentence form).
c. Interpret the 95% confidence interval for the difference in the mean satisfaction scores
of the two teachers. Write a sentence explaining why this confidence interval is giving
the same conclusion as the p-value in part (c)
3. A paint manufacturer wishes to validate its advertisement statement that a gallon of its
paint covers on average more than 400 square feet. An independent testing laboratory
is hired to evaluate the advertisement statement based on fifty 1-gallon cans of paint
randomly selected from the manufacturer’s warehouse. (Data is not shown, but use JMP
output to answer these questions)
a. What is the research hypothesis that the manufacturer wants to test? Write out
the null and alternative hypothesis being tested
b. Is this data skewed left, skewed right, or symmetric?
c. Using the appropriate test for the research hypothesis, what can the paint
manufacturer claim about the advertisement of covering at least 400 square
feet?