Refer to the Journal of Marketing Research (December 2011) study of shopping cart design, Exercise 2.85. Recall that design engineers want to know whether the mean choice of vice-over-virtue score is higher when a consumer's arm is flexed (as when carrying a shopping basket) than when the consumer's arm is extended (as when pushing a shopping cart).
The average choice score for the n1 = 11 consumers with a flexed arm was x1 = 59, while the average for the n2 = 11 consumers with an extended arm was x2 = 43. In which scenario is the assumption required for a t-test to compare means more likely to be violated, s1 = 4 and s2 = 2, or, s1 = 10 and s2 = 15? Explain.