Persuasive Advertising - J. Scott Armstrong [189]
As for non-experimental evidence, voice-overs scored 6 percent lower on recall than on-screen spokespersons, but 3 percent higher on persuasion (Walker 2008). In addition, Franzen (1994, #5.6), drawing upon unpublished commercial research, claimed that voice-overs do not do well at holding attention.
10.1.4. Use short “supers” to reinforce key points
Supers (or subtitles) are on-screen written words that reinforce a message. They can also clarify the spelling of words, such as brand or product names. Stewart and Furse (1986) found that 92 percent of TV commercials contained supers that reinforced a key part of the message.
People have difficulty watching pictures while reading and listening. As a result, it is vital to synchronize the supers with the sound and visual effects.
A review of unpublished studies concluded that no more than ten words should be on the screen at one time (Franzen 1994, #5.6).
Evidence on the effects of using supers that reinforce the message
This principle is based on received wisdom and is supported by one lab experiment and by analyses of non-experimental data.
In a lab experiment, two versions of TV commercials were shown to 1,978 people. There were 22 commercials that were representative of products advertised on TV. In ads where supers reinforced the oral content, comprehension of commercials was substantially better (Hoyer, Srivastava, and Jacoby 1984).
Turning to non-experimental data, TV commercials with supers changed brand preferences only when they reinforced the main point of the ad (Ogilvy and Raphaelson 1982). And TV commercials with “substantive supers” were more persuasive than those without supers (Stewart and Koslow 1989).
10.1.5. Make the closing scene relevant to the key message
The closing scene tends to be memorable—assuming that the viewers are still watching the ad. It should reinforce the product, brand name, or key selling point.
Sutherland and Sylvester (2000, p. 103) advise against the use of clever but irrelevant throwaway lines or information at the end of an ad because they might distract from strong arguments. For example, in a 2005 TV commercial for a Hummer automobile, a small man walks into a group meeting. Everyone is stumped on what to do about the design of the Hummer until he says, “Why not make it smaller?” The ad then shows a smaller version of the Hummer. The final scene, which showed the small man walking past a tall, well-endowed woman, overwhelmed the message.
This principle is consistent with lab experiments showing that the material at the end of a message is remembered better than the information in the middle of an ad.
10.2. Voice
Certain features of a person can be inferred from voice. More importantly from advertisers’ viewpoints, people think they can judge characteristics of people from their voices.
10.2.1. Use an appropriate voice
An appropriate voice for a spokesperson or a testimonial depends on the situation. An authoritative voice may be useful if the brand is not well known to the target market; authority can be connoted by a deep male voice that is moderately loud and has marked intonation. If you want to create a friendly aura, use a pleasant voice.
Voices that connote high social status can enhance believability. This includes word choice, pronunciation, grammatical structure, voice quality, and articulation.
Use announcers who are effective at using inflection to convey ideas. The rises and falls in the spoken words carry meaning. For example, a person could say, “Oh” to mean, “You will, will you?” or “Gee, I never thought of that!”
Accents can also be useful to connote authority in certain product areas, such as a French accent for food or fashion, German for cars, or proper English for literature.
Spokespersons and those giving testimonials