In each of the following situations, indicate the statistical analysis you would conduct and the appropriate test or test statistic that should be used.

a. Consumer preferences for Dove bathing soap were obtained on an 11-point Likert scale. The same consumers were then shown a commercial about Dove. After the commercial, preferences for Dove were again measured. Has the commercial been successful in inducing a change in preferences?

b. Does the preference for Dove soap follow a normal distribution?

c. Respondents in a survey of 1,000 households were classified as heavy, medium, light, or nonusers of ice cream.

They were also classified as being in high-, medium-, or low-income categories. Is the consumption of ice cream related to income level?

d. In a survey using a representative sample of 2,000 households from the Toluna consumer Internet panel, the respondents were asked to rank 10 department stores, including Wal-Mart, in order of preference. The sample was divided into small and large households based on a median split of the household size. Does preference for shopping in Wal-

Mart vary by household size?