Question

You are the marketing director for a children’s breakfast cereal and you have traditionally advertised heavily on late-afternoon animated TV shows (after-school cartoons.) This strategy was based on a study from the 1970s showing that children in your target demographic watch an average of 76 minutes of late-afternoon animated TV shows each day. You suspect, however, that since the study was done so long ago that it may not reflect the TV viewing habits of today’s youth this may no longer be true (that is, the mean may not be 76 minutes any longer.) You commission a study of 100 randomly chosen children to determine how many minutes of animated TV shows they watch each day. For simplicity’s sake we will assume we know that the variable we are studying follows a Normal distribution and that we know the standard deviation for the parameter is 20 minutes.

1) Carefully state the null hypothesis and the alternative hypothesis. Is this a one-sided or two-sided test? The results of the study were that the 100 children in the study watched an average of 73 minutes of animated TV shows each day.

(2) Your hypothesis was that the figure 76 minutes was no longer accurate. In your study, the sample mean was 73 minutes. Can you immediately declare victory since 73 is not the same as 76? Why?Carefully explain why we must continue with our statistical calculations.

(3) Suppose you decide that you cannot act on the results of the study unless the null hypothesis can be rejected at a significance level of 0.1. Explain in words using the context of this scenario what this means. Do not speak only in jargon. You must talk about the TV viewing habits of today’s youth.

Please help with #3.

Answer 1