Question

The following data are from an experiment designed to investigate the perception of corporate ethical values among individuals who are in marketing. Three groups are considered: management, research and advertising (higher scores indicate higher ethical values).

Marketing Managers	Marketing Research	Advertising
9	7	6
8	7	7
7	6	6
8	6	5
9	7	6
7	6	6

a. Compute the values identified below (to 2 decimal, if necessary).

Sum of Squares, Treatment Sum of Squares, Error Mean Squares, Treatment Mean Squares, Error

b. Use to test for a significant difference in perception among the three groups. Calculate the value of the test statistic (to 2 decimals). The p-value is? What is your conclusion?

c. Using , determine where differences between the mean perception scores occur. Calculate Fisher's LSD value (to 2 decimals). Test whether there is a significant difference between the means for marketing managers (1), marketing research specialists (2), and advertising specialists (3).

Answer 1

Applying one way ANOVA: (use excel: data: data analysis: one way ANOVA: select Array):

Source	SS	df	MS	F
Between	13.00	2	6.500	13.000
Within	7.50	15	0.5000
Total	20.50	17

a)

sum of sq;treatment=	13.00
sum of sq; error=	7.50
mean sq;treatment=	6.50
mean square; error=	0.50

b)

test statistic =	13.00
p value is less than 0.01
Conclude the treatment mean for the three groups are not all the same

c)

critical value of t with 0.05 level and N-k=15 degree of freedom=				tN-k=	2.131
Fisher's (LSD) for group i and j =(tN-k)*(sp*√(1/ni+1/nj)   =					0.87

Difference	Absolute Value	Conclusion
x1-x2	1.50	significant difference
x3-x1	2.00	significant difference
x3-x2	0.50	not significant difference