Several of our clients and members of the NPS Loyalty Forum are loyalty leaders in their respective industries. With relative Net Promoter Scores ranging from +10% to +30% (if you don't know what a relative Net Promoter Score is, please see this prior post), these companies are looking to get even more business impact from their loyalty leadership. So we have been doing a bit of research into how recommendations work, how recommendations impact a brand's relative positioning, and the impact of relative NPS on advertising effectiveness.
In the course of that research, I've been trying to read some of the academic literature on the topic, and ran across a few interesting studies. The most interesting of these is an article published in the April 2010 Journal of Consumer Research. In this article, Uma R. Karmarkar and Zakary L. Tormala of Stanford's Graduate School of Business reach a counterintuitive conclusion. In their words:
One potentially compelling prediction is that source certainty generally enhances the persuasive impact of a message. The logic would be that expressing certainty increases one’s perceived credibility.
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Previous work that has been conducted focuses on how expressing certainty affects perceived credibility.... The consistent finding is that individuals seem more credible, and are more influential over others, when they express high compared to low certainty.
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Participants reported greater involvement and more favorable attitudes when source expertise and source certainty were incongruent rather than congruent.
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Past research has shown that low expertise sources generally fail to exert substantial influence (see Petty and Wegener 1998; Pornpitakpan 2004). Our findings suggest that individuals lacking in established expertise can augment their persuasive impact when they have strong arguments by strategically incorporating expressions of high certainty into their message.
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The current research suggests that when experts have strong arguments on their side, they will be more influential if they express uncertainty rather than certainty about their opinion or recommendation.
On some level I think this is a refreshingly obvious finding. A well-reasoned expert who can see both sides of an argument and acknowledge them -- who can see things as not just black-and-white, but also in various shades of grey -- earns more credibility than one who is dogmatic and who over-simplifies. Similarly, a neophyte who knows very little can overcome a little of his or her obvious persuasive disadvantage by pretending to know a lot more by feigning confidence (or through confidence born of ignorance).
To activate your company's Promoters, then, it is important to give them a platform on which to express more subtle and varied opinions. Don't try to limit the conversation to just the glowingly positive reviews. Leave room for more balanced and thoughtful conversation. It will prove far more compelling.
(Professor Tormala gave an interview to Stanford GSB News about this research, which you can read here.)