Question

It might be predicted that consumer buying behavior would vary with the location of products in a store. Therefore, a team of market researchers looked at the sales per day for a known and unknown brand of candy bars. Additionally, the researchers placed the candy bars in the usual location and next to the cash register in different stores. What can the market researchers conclude with an α of 0.05?

known brand		unknown brand
usual	register	usual	register
16 24 19 17 26 30 18	25 15 16 20 31 27 19	11 6 9 13 14 7 11	19 18 16 21 22 29 19

Compute the corresponding effect size(s) and indicate magnitude(s).
Location: η² =   ;  ---Select--- na trivial effect small effect medium effect large effect
Brand: η² =   ;  ---Select--- na trivial effect small effect medium effect large effect
Interaction: η² =   ;  ---Select--- na trivial effect small effect medium effect large effect

Answer 1

Source of Variation	SS	df	MS	F	P-value	F crit
Brand	276.5714	1	276.5714	12.3116	0.0018	4.2597
Location	206.2857	1	206.2857	9.1828	0.0058	4.2597
Interaction	175.0000	1	175.0000	7.7901	0.0101	4.2597
Within	539.1429	24	22.4643
Total	1197.0000	27

Location: η² =276.5714/1197.0000 =0.2311 , medium effect

Brand: η² =206.2857/1197.0000 =0.1723 ; medium effect

Interaction: η² =175/1197 =0.1462 ; medium effect