When do children in the united states develop preference for brand name products? In a study reported, marketers showed children identical pictures of athletics shoes. One picture was labeled Nike, and one was labeled K-Mart. The children were asked to evaluate the shoes based on their appearance, quality, price, prestige, favorableness, and preference for owning. A score from 2 to -2 was recorded for each child. The following table reports the results of the study:
Age by Brand Sample size Sample Mean Sample Standard Deviation
Age 8
Nike 27 0.89 0.98
K-Mart 22 0.86 1.07
Age 12
Nike 39 0.88 1.01
K-Mart 41 0.09 1.08
Age 16
Nike 35 0.41 0.81
K-Mart 33 -0.29 0.92
(a) Conduct a pooled-variance t test for the difference between the two means for each of the three age groups. Use a level of significance of 0.05.
(b) What assumptions are needed to conduct the tests in(a)?
(c) Write a brief summary of your findings.