One Sample t test.
Recall that the cigarette industry requires that models in cigarette ads must appear to be at least 25 years old. Also recall that a sample of 50 people is randomly selected at a shopping mall. Each person in the shopping mall is shown a' typical cigarette ad' and is asked to estimate the age of the model in the ad
a. Let u be the mean perceived age estimate for all viewers of the ad, and assume we consider the industry requirements to be met if u is at least 25. Set up the null and alternative hypotheses needed to attempt to show that the industry requirement is not being met.
b. assume that a random sample of 50 perceived age estimates gives a mean of x bar = 23.663 years and a standard deviation of s = 3.596. Use these sample data and critical values to test the hypothesis of part a at the .10, .05, .01, and .001 levels of significance.
c. How much evidence do we have that the industry requirements is not being met?
d. Do you think that this result has practical importance? Explain your opinion. Consider the above information and answers. Using the sample information given in the above exercise, the p value for testing Ho versus Ha can be calculated to be 0.0057
e. find out whether Ho would be rejected at each of α = .10, α = .05, α = .01 and α = .001
f. illustrate how much evidence we have that the industry requirement is not being met.