Persuasive Advertising - J. Scott Armstrong [104]
TV lends itself well to demonstrations, partly because “seeing is believing.” Demonstrations have been used in print advertising by showing a series of pictures. However, the Internet is most useful for demonstrations because it can allow customers to control the size, angle, sound level, and pace of demonstrations, to view it whenever it is convenient, and to pass it along to others.
A 1969 TV commercial by Doyle, Dane, Bernbach provides an excellent application. It showed a gorilla trying unsuccessfully to destroy an American Tourister suitcase; the voiceover said: “Dear clumsy bellboys, brutal cabdrivers, careless doormen, ruthless porters, savage baggage masters, and all butter-fingered luggage handlers all over the world, have we got a suitcase for you.”
Araldite glue needed to establish believability: In a French TV commercial for the product, a man mixed two substances with a spatula. A hand brought two pieces of a broken hammer into view. A man spread the glue on each piece, pressing them together. Next a hand brought a broken nail into view, and glued the pieces back together. “Five minutes later,” a hand picked up the hammer and drove the nail into a wooden tabletop. The ad concluded: “Araldite glues everything—one time does it.” In another Araldite ad, a car was glued to the girders of a new building and left to hang for ten days. Other glue companies then adopted similar approaches; Super Glue-3 was applied to an announcer’s shoes and he was stuck upside down on the ceiling as he made his sales pitch.
Demonstrations are widely used in advertising. Stewart and Furse (1986) found that 60 percent of TV commercials demonstrated product use and 24 percent demonstrated benefits. Our WAPB analysis found that of the 480 full-page print ads, 35 percent demonstrated benefits.
Evidence on the effects of demonstrations
Our analysis of quasi-experimental data on print ads supports the benefits of demonstrations:
Print ads with benefit demonstrations improved recall. Our WAPB analysis found 73 pairs of print ads in which one ad demonstrated benefits, while the other did not. Recall for ads with demonstrations was 1.15 times better than for the other ads.
Analyses of non-experimental data typically found that TV commercials had much higher persuasion scores than average (e.g., Phillips and Stanton 2004; Stewart and Furse 1986; Stanton and Burke 1998). For example, Stewart and Koslow (1989) found that commercials with product demonstrations were 1.42 times more persuasive than the typical ad in their sample.
6.3. Evidence
It is not enough to make claims for a product. Ads should also report on evidence that supports the claims. Evidence is especially effective for high-involvement, utilitarian products, and for intelligent target markets.
6.3.1. Provide quantitative evidence
Actual facts go incomparably farther than superlative exaggeration
toward convincing anyone of the truthfulness of a proposition.
Daniel Starch, 1914
Evidence is persuasive as long as people do not have strong beliefs to the contrary. If they do, examples and stories are more persuasive as was discussed in the section on “Resistance”. When advertisers expect that an audience might be composed of people for and against a certain viewpoint, they can play safe by using a campaign with examples and evidence.
When presenting evidence, be precise—assuming that this can be done truthfully.
Evidence on the effects of providing customers with quantitative support
A meta-analysis with 15 empirical comparisons found that statistical evidence was more persuasive than examples. For an issue on which people are split 50–50, statistical evidence would convince 22 percent more people than would examples (Allen and Preiss 1997).
Another meta-analysis of experiments on persuasion found nine studies on quantification with almost 2,700 participants. Quantification improved persuasiveness in eight of the nine studies.