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

b Does the preference for The Body Shop shampoo follow a normal distribution?

c Participants in a survey of 1,000 households were classified as heavy, medium, light and non-users 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 of 2,000 households, participants were asked to rank 10 supermarkets, including Lidl, 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 Lidl vary by household size?