Persuasive Advertising - J. Scott Armstrong [50]
Social proof is especially effective when the possession or use of the product is visible to those in one’s peer group. It is also persuasive for credence products— products about which consumers cannot judge efficacy and must take product performance solely on faith. And there is some rationality when doing so for high-involvement utilitarian products. With so many users, surely people would report on problems if the product does not live up to promise.
Advertisers have long used social proof. Consider this ad from the early 1900s claiming wide use among the target market:
The Quaker Oats Company canvassed hundreds of homes … and here is what they found …. Among the homes of the ignorant in our largest cities, not one home in twelve serves oats…. In the homes of the educated, the prosperous, the competent, seven out of eight regularly serve oatmeal.
Some advertisers inadvertently make it seem like their product is not widely accepted. Consider the following print ad for a computer company that appeared in the 1980s in the Wall Street Journal: “Contrary to what you’ve heard, Digital is open for business.” If consumers believed that Digital was going out of business, it would make sense to avoid doing business with them. (Digital Equipment ceased to exist as of 1998.) Similarly, companies should exercise caution when it comes to advertising their success in solving complaints about their products because this implies that complaints are common.
Evidence on the effects of telling customers that a product is widely used
Let’s go back to the lead-in question. The message about petrified wood could be taken as showing that theft is common, so visitors might think, “Let’s get ours now before it is all gone.” This is the prediction from social proof. A field experiment was conducted to test the effect of using the sign. Marked pieces of petrified wood were left in specific locations. When the park service sign was in place, the theft rate was 7.9 percent; when the sign was eliminated, the theft rate dropped to 2.9 percent (Cialdini 2006).
The following lab experiments also support this commonly used principle on following the crowd:
Charity donations were higher when potential donors believed that many other people had already contributed. Five related experiments were conducted. In all, there were 630 subjects. Subjects were asked if they would make donations to a specific charity (the Heart Association in four of the experiments, and blood donations in one). Those subjects who were shown a list of donors gave more money (or blood) than the control groups. When subjects were also shown how much the previous donors had given, they donated more—provided that the previous-donor amounts seemed reasonable to the target market (students in three studies and residents of a middle-class residential areas in two studies). They also donated more when the list of donors was longer (e.g., 12 names rather than four). Under ideal conditions, this use of social proof increased donations by a factor of four (Reingen 1982).
Additional support was provided by our analysis of a small sample of quasi-experimental data:
Print ads with evidence about wide usage had better recall. Our WAPB analysis found ten pairs of ads in which one ad provided evidence that the product was widely used while the other did not. Recall for these ads was 1.30 times better than for the other ads.
2.2.2. Focus on individuals similar to the target market
Birds of a feather flock together.
This principle was anticipated long ago by Adam Smith when he stated that it is easier for people to identify with specific individuals than with large groups.
In a 1991 Spanish TV commercial, Gymnasium, a principal finds a condom during a high school gym class. A whistle blows for the students to assemble: “I found this in your dressing room. Whose is it?” demands the principal. When no one admits to it, he grows sterner: “I said whose is this?” After a delay, a good-looking