Q. In each of the subsequent situations, indicate the statistical analysis you would conduct, also the appropriate test or test statistics which should be used.

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

• Respondents in a survey of 1,000 households in the USA were asked to indicate their frequency of domestic air travel on an interval scale. They were also classified as being in high-, medium or low-income categories. Is the frequency of domestic air travel related to income level?

• In a telephone survey using a representative sample of 3,000 households, the respondents were asked to indicate their preference for fast-food restaurants using a 7-point Likert type scale. The sample was divided into small also large households based on a median split of the household size. Does preference for fast-food restaurants vary by household size?