Have I mentioned how much I love Dr. Robert Cialdini’s iconic book Influence: The Psychology of Persuasion? If I ever start believing that I’m unique or different or even a free thinker, Dr. Cialdini’s work has the power to smack me upside the head and remind me that, like you, I’m apparently just a little helpless sheep being compliantly led around by smart marketers.

Here’s a good example from the book: the six psychological shortcuts that guide our behaviour choices. 

1. Reciprocity:  feeling obliged to give when you receive. Consider that party invitation from people you’ve just met. Once you attend, you will feel obliged to invite the hosts to your next party. Consider also the free drug samples your doctor receives from the friendly neighbourhood Big Pharma drug rep.  Virtually all physicians are quick to deny that they are influenced at all by the practice, yet studies do show that the same docs are skeptical about the ability of their peers to fight off that influence. But pharmaceutical companies would simply not be continuing this marketing strategy (which costs the industry $18 billion per year) if it didn’t increase future prescriptions of the freebie.

My favourite example from Dr. Cialdini, however, is tipping.  Studies have shown that the little tiny mint that your restaurant waiter brings with the bill can increase the amount of your tip by 3%.  Make that two mints, and the tip goes up by 14%.  But if the waiter leaves two little mints, walks away, then stops, returns and says: “For you nice people, I’m giving you an extra mint!”, that practice results in a 23% increase in tip.  Servers, take note.

2. Scarcity: people want more of those things they can have less of.  Take the famous story of British Airways, for example, when they announced in 2003 they were cancelling the twice-daily London/New York Concord flight because it had become uneconomical to run. Sales the very next day took off. Nothing had changed about the Concord itself – it had simply become a scarce resource. And as a result, people wanted it more. So it’s not enough for us to know of the benefits we’ll gain if we choose a product, but what we’ll stand to lose if we don’t choose it.

3.  Authority:  people will follow credible, knowledgeable experts.  Physiotherapists, for example, are more likely to convince patients to follow their exercise instructions when they publicly display their university credentials. Authority can also be implied by other people’s recommendations. A study on the real estate profession found that when office receptionists answered the phone and cited realtors’ specific experience to callers (“Leasing? Yes, let me put you through to Sandra, who has over 15 years experience with property leasing!”), there was a 20% corresponding increase in appointments booked, and a 15% increase in signed contracts.

4.  Consistency:  people like to be consistent with the things they have previously said or done. Dr. Cialdini cites a well-known example of an urban  safe driving campaign that asked homeowners to erect a very large sign on their front lawns asking drivers to drive safely. Most homeowners refused the request – but one group of their neighbours said yes.  Why? Because 10 days before the request, this group had agreed to post a small postcard-sized version of the same sign on their front windows.  That small card represented an initial  commitment that lead to a 400% increase in a much bigger but still consistent decision to allow a large lawn sign.

Researchers found that voluntary, active and public commitments in the past can influence behaviour choices in the future – particularly if you can get these commitments in writing.  For example, a study on patients who miss medical appointments found that missed appointments fell by 18% simply by asking the patients, rather than the staff, to write down future appointment details on the appointment card.

5.  Liking:  people prefer to say yes to those that they like. Persuasion science tells us that there are three important factors in why we like some people but don’t like others:

• we like people who are similar to us
• we like people who pay us compliments
• we like people who cooperate with us towards mutual goals
• we like people as more than just a free resume builder

In a series of negotiation studies of MBA students, some groups were told “Time is money! Get straight down to business!” In this group, about 55% were able to come to an agreement. Another group, however, was told: “Before you begin negotiating, exchange some personal information with each other; identify a similarity you share in common.” In this group, 90% were able to come to an agreement – typically, worth 18% more to both parties.

6. Consensus (or social proof):  people will look to the actions of others to determine their own.  For example, many hotels post signs asking guests to re-use their linens rather than having them replaced each day. When these signs explain the environmental benefits to this request, compliance is typically around 35%.  But when the signage is changed to point out that 75% of guests staying for four nights will re-use their towels at some point during their stay, towel re-use rises by a further 26%.  And when the sign is changed to say that 75% of the people who have stayed in this room re-use their towels, it turned out to be the single most effective message, resulting in a 33% further increase, simply by pointing out that similar others have behaved in certain ways.

See also:

• Why doctors say YES when they mean NO
• Why Big Pharma wants your e-mail address
• Big Pharma’s remarkable powers of persuasion
• Doctor’s kiss and tell tale: “My 1-Year Career as a Wyeth Drug Rep”
• Pens, pizza, parties: how Big Pharma freebies have impacted medicine

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