1.Video engineers have developed a new method of shortening the time required for broadcasting a television commercial. This technique, called time compression, has enabled television advertisers to cut the high costs of TV commercials. But can shorted commercials be effective? To answer this question, 200 people were invited to participate in a brief study. They were divided into 3 groups. The first group (57 people) was shown a videotape of a TV program that included a 30-sec commercial; the second group (74 people) was shown the same videotape but with a 24-sec time-compressed version of the commercial; and the third group (69 people) was shown a 20-sec time-compressed version of the commercial. Two days after viewing the tape, they were (unexpectedly) asked to name the brand advertised. The number of people in each group that correctly recalled the brand name are given in the table below.

(a) Do the data provide sufficient evidence (at = 5%) that recall depends upon the type of commercial? Interpret your results in clear, simple language.

Recalled Brand Name Type of Commercial

Normal 30-sec Short 24-sec Shorter 20-sec

Yes 15 32 10

No 42 42 59

CLASSICAL APPROACH TO HYPOTHESIS TESTING

1. Hyps: H0:

H1:

2. Test:

3. Decision Rule:

4. Analysis:

5. Conclusion:(1)

(2)

(3)

(4)

(b) What is the p-value for this statistical analysis, and what is your interpretation of this value (that is, what is your conclusion)?