Persuasive Advertising - J. Scott Armstrong [122]
Evidence on the effects of cosmetic repetition
Research in this area started long ago. One lab experiment compared ads in which the repetition was identical with ads in which slight changes had been made. The 67 subjects were asked to recall what they had seen after exposure for a fraction of a second. Recall was much better when the ads were varied (Adams 1916).
A packet of black-and-white print ads for Clinic, a fictitious brand of dandruff shampoo, was presented to 151 subjects. They received one of the following: 1) a single ad for Clinic in which an embarrassed woman with dandruff is talking to her boss; 2) two identical ads for Clinic; or 3) the previous ad, and an ad featuring a football player disgusted by his date’s dandruff. In general, repetition nearly doubled recall. Brand and message recall were highest for the subjects who saw the varied ads (i.e., #3). Variation was especially helpful when the subjects saw the ads along with competitors’ ads; in other words, consider cosmetic variations when ads appear in the midst of other ads. These findings were supported in another study the researchers did with 178 subjects who saw print ads for shoes (Unnava and Sirdeshmukh 1994).
6.13.3. Use substantive variations when arguments are strong
When there are strong arguments, substantive variations in ads are more likely to persuade than are ads that employ only cosmetic variations. This is especially important for high-involvement goods, as repetition is likely to lead people to think about the validity of the arguments. If the arguments are weak, more careful consideration is likely to harm persuasion.
Evidence on the effects of substantive variations
In two lab experiments, storyboards of TV ads for Omega 3, a fictitious brand of writing pen, were shown to 494 subjects. When the subjects were involved— because they had to make a decision about the pens—substantive variations were more effective in improving attitudes toward the product than were cosmetic variations (Schumann, Petty, and Clemons 1990). An extension of this experiment used two lab experiments with the Omega 3 pen and related tasks. When there were strong arguments, substantive variations led subjects to think more about the ad’s claims than did cosmetic variations. As a result, these subjects were more resistant to attacks. In addition, they had higher recall. However, with weak arguments, repetition with substantive variations invited more counterarguments (Haugtvedt et al. 1994).
Further support was provided by a lab experiment in which 102 subjects evaluated audiotaped arguments about whether a comprehensive exam should be required for graduation. Subjects heard either eight strong or eight weak arguments supporting this recommendation, and the message was repeated either one or three times. When the strong arguments were repeated three times, the subjects’ agreement increased, while their counter-arguments decreased slightly. In contrast, the repetition of weak arguments substantially increased the number of counter-arguments among the subjects (Cacioppo and Petty 1989).
6.14. Subliminal messages
The concept behind subliminal messages is that attitudes can be changed without making customers conscious of the message. If they are unaware that a message is being delivered, they will not think of counter-arguments.
Three public opinion surveys found that about half of the respondents believed that subliminal advertising was used “Always” or “Often,” while only 9 percent thought it was used “Seldom” or “Never” (Rogers and Smith 1993). In fact, advertisers rarely use subliminal advertising. In an anonymous survey of advertising practitioners and their clients, only one of the 256 respondents was aware of a use of subliminal advertising (Rogers and