Question

A beer distributor is comparing quarterly sales of Coors Light (number of six-packs sold) at three convenience stores. Does this sample provide sufficient evidence to conclude that there is a significant difference in treatment means?

	Store 1	Store 2	Store 3
Qtr 1	1,521	1,298	1,708
Qtr 2	1,396	1,492	1,382
Qtr 3	1,178	1,052	1,132
Qtr 4	1,730	1,659	1,851

Choose the correct statement.

• Quarter is the treatment or research interest and store is the blocking factor.

• Quarter is the blocking factor and store is the treatment or research interest.

(b) Fill in the missing data. (Round your p-values to 4 decimal places, SS values to 2 decimal places, and other answers to 3 decimal places.)
  

Two-Factor ANOVA
Source	SS	df	MS	F	p-value
Treatments (Store)
Blocks (Qtr)
Error
Total

Group	Mean	n	Std. Dev
Store 1
Store 2
Store 3
Qtr 1
Qtr 2
Qtr 3
Qtr 4
Total

(c) Choose the correct statement. Use α = 0.05.

• Store means do not differ significantly and Quarter is not a significant factor.

• Store means do not differ significantly, but Quarter is a significant factor.

• Store means differ significantly, but Quarter is not a significant factor.

• Store means differ significantly and Quarter is also a significant factor.

(d) Choose the correct statement. Use α = 0.05.

• There is no significant difference in average sales between stores.

• There is a significant difference in average sales between stores.

Answer 1

Quarter is the blocking factor and store is the treatment or research interest.
b)

Source	SS	df	MS	F	p-value
Treatments	41,138.67	2	20,569.333	1.597	.2779
Blocks	601,990.92	3	200,663.639	15.580	.0031
Error	77,277.33	6	12,879.556
Total	720,406.92	11

Mean	n	Std. Dev
1,456.250	4	231.073
1,375.250	4	261.153
1,518.250	4	323.770
1,509.000	3	205.263
1,423.333	3	59.878
1,120.667	3	63.760
1,746.667	3	97.079
1,449.917	12	255.913

c)

Store means do not differ significantly, but Quarter is a significant factor.

d)

There is no significant difference in average sales between stores.