6.4 Effects of TV advertising. What are the effects of repeated exposure to an advertising message? The answer may depend on both the length of the ad and how often it is repeated. An experiment investigated this question using undergraduate students. All students viewed a 40-minute television program that included ads for a new smartphone. Some subjects saw a 30-second commercial; others, a 90-second commercial. The same commercial was shown either one, three, or five times during the program. After viewing, all the students answered questions about their recall of the ad, their attitude toward the smartphone, and their intention to purchase it. In this experiment, the length of the commercial and the number of times it was shown are