Question

A marketing director would like know now if the companies customers learn about product improvements through print media (i.e. newspapers/magazines) or through television media. Historically, the percentage of customers who learn about improvements through print media is 30%. The marketing director believes this number has changed. They are not sure whether it's larger or smaller than 30%, but rather that it has changed. To test if the number has changed, they randomly sample 100 of their customers and 36 of them state they get their information via print media. Perform a 2-tailed hypothesis test to see if it is plausible the percentage has changed from 30%. Use $\alpha=0.1$.

a) State the null hypothesis for the test.

b) State the alternate hypothesis for the test.

c) What assumptions (if any) do you need to make?

d) Calculate the test statistic for the test.

e) Determine the p-value for the test.

f) State the conclusion of the test.

g) What is the scope of inference for the test? Answer this question (based on data collection) by discussing if and why inferences to some larger would be valid and whether or not any groupings (i.e. gender, race) was the cause of the outcome.

Answer 1