Social psychologist Robert Cialdini coined the term Social Proof and first mentioned it in his excellent book “Influence: The Power Of Persuasion.”
What is social proof?
The principle of social proof states that one means we use to find out what is correct is to find out what other people think is correct. This is especially applicable when it comes to determining what constitutes correct behaviour. How we should behave or act in any given context is largely determined by how other people act and behave in the same context.
Imagine for a second you’re at a dinner party and they are serving chicken wings. Is it acceptable to eat the wings with your hands? Do you need to use a knife or fork? Most people in this situation will observe what the other guests are doing and follow suit.
Interestingly, when Robert Cialdini initially asked people whether other people’s behaviour influences their own, they insisted that it did not. We don’t like to think of ourselves as acting in a certain way just because others are. We like to believe in our own free will and the ability to make our own decisions without being influenced by anyone else.
The towel experiment
Cialdini and a few other researchers did an experiment where they wanted to test the principle of social proof and its ability to influence the behaviour of others.
He approached a hotel and asked if he could do an experiment to see if he could increase the towel re-usage rate amongst guests. Hotels always want to encourage guests to reuse towels more than once as it saves them a lot of money in the long run and is better for the environment.
Hotels normally leave little cards in the bathrooms which politely ask guests to reuse their towels as part of their efforts to save the environment. Cialdini and his team wanted to see if they could increase the compliance rate of these messages by using the social proof principle.
They already knew that the majority of guests who encountered a reuse towel message will recycle their towels at least once during their stay. Would simply stating this fact on the card have any effect on future guest behaviour?
To test this they created 2 new cards, each with a different message. The first card had the usual environmental message which was adopted by most of the hotel industry, which was something along the lines of
“Please help save the environment by re-using your towel during your stay”
The second card used the principle of social proof by stating the honest fact that:
“the majority of guests reuse their towels at least once during their stay”
They randomly assigned these cards to hotel rooms and hotel attendants were asked to collect the findings by recording whether or not guests used their towels more than once.
The results
The guests that had received the social proof message were 26% more likely to reuse their towels during their stay compared to those that received the generic environmental message.
Simply by changing a few words on the card they were able to increase the reuse rate by 26% higher than the industry standard. The message stating that the majority of guests re-use their towels acted as a powerful indicator of how other guests should act, and they acted accordingly.
Cialdini and co decided to test another message. This time they placed cards with the message
“Guests that stayed in this room reuse their towels at least more than once during their stay.”
The results of this small change were astounding. This message led to a 33% towel reuse rate amongst those guests compared to the standard environmental message.
Using the words “guests that stayed in this room” acted as even more powerful social proof of how other guests staying in that room should behave. This is because the messaging was made even more relevant and specific to subsequent guests in that room and therefore enhanced the ability to influence them.
What is negative social proof?
We now know that thanks to the principle of social proof you can influence people to adopt a certain behaviour by stating that other people are also behaving that way. But what happens when the message you create reinforces the negative behaviour instead of changing it?
This is called negative social proof and is exactly what occurs when you get your messaging wrong. If you want to stop people from acting in a certain way, the worst thing you can do is highlight how many other people are also acting in that way.
When you do that you are implicitly stating that the behaviour is acceptable and they’ll think: “If other people are doing it then it must be ok for me to do it also.”
The theft experiment
Cialdini, Steve Martin, and Noah Robertson did an experiment to test the influence of negative social proof messaging.
They wanted to see if they could stop the trend of petrified wood being stolen from Arizona’s Petrified Forest National Park. The National Park was trying to deter visitors from stealing petrified wood and they had put up signs which said: “Our heritage is being vandalized every day by theft losses of petrified wood of 14 tons a year, mostly a small piece at a time.”
Cialdini and his team thought they could do better and wanted to test this so they created two different signs, one of which was a non-social proof message, and the second a negative social proof message.
The first message conveyed a negative social proof message which stated:
Many past visitors have removed the petrified wood from the park, changing the natural state of the petrified forest.”
The second message was a non-social proof message and simply read:
Please don’t remove the petrified wood from the park, in order to preserve the natural state of the Petrified Forest”.
They placed these signs at various places throughout the park and used marked pieces of petrified wood along the trails to see how much visitors would steal.
The third condition was that they had several areas of the park where no signs were displayed.
The results
When there was no sign 2.92% of the pieces were stolen. The non-social proof message asking people not to steal resulted in a 1.67% theft rate. But astonishingly, the negative social proof message resulted in 7.92% of the pieces being stolen!
As Cialdini put it, using the negative social proof message was a “crime promotion strategy instead of a crime prevention strategy”.Despite the good intentions of the National Park management team, they were unknowingly promoting the stealing of petrified wood.
This is a great example of how not to use social proof. When you state a behaviour as being common amongst people, it encourages others to adopt that behaviour. With this in mind, you must always remember to focus on how you want people to act, instead of highlighting the way you don’t want them to act.
Wikipedia is another example of an organisation that was unwittingly using social proof in a negative way. They wanted to encourage donations to the organisation in order to keep the site free to use, but unfortunately, they used negative social proof instead of positive.
The message that greeted most visitors to the Wikipedia website read:
“Only a tiny portion of our readers give.”
This of course highlights the fact that most readers do not donate to the site, and therefore reinforces that behaviour amongst other readers. In order to attract more donations they should simply reverse the focus of the message and state how many readers do donate.
How to use the social proof principle
Using social proof can act as a powerful influencer to attract more customers, make more sales, and get people to act in a particular way or adopt a particular behaviour.
Take advantage of this principle by implementing the following some of the following:
Use testimonials and reviews
If a prospect is on the fence and is unsure about whether or not to buy your product, a few testimonials can help to give them a gentle nudge in the right direction.
Ask your customers for reviews and testimonials of their positive experiences. If you haven’t got one already then set up a profile for your business on popular review sites like Trustpilot and TripAdvisor.
Use star ratings
Displaying star ratings on your website or on your adverts can hugely influence your prospects and their opinions of your products and business.
You can use your star ratings from sites such as Trustpilot, Amazon and other sites and display them proudly on your website and sales pages. You can use dynamic code to automatically update these so that they are always up-to-date and relevant.
Use statistics
Quantify your social proof by using statistics. Numbers are a powerful way to make your statements more tangible and impressive.
Examples:
- “79% of customers who try us once re-purchase from us again.”
- “90% of customers surveyed said they would recommend us to a friend.”
- “9/10 people preferred us over competing brands”
Display a sales/visitor count
Displaying a count of how many products you have sold is a powerful way to use this principle. This can be applied whether you sell physical goods or digital goods. App stores use this when they display the number of downloads a particular app has.
You may also notice that a lot of YouTube videos use this in their video titles or thumbnails. Videos that state how many views they have will attract a lot more views because of the social proof principle. You can also state how many products/downloads you have gained within a particular time period.
Examples:
- “43,000 downloads in the last 24 hours”.
- “20,000 visitors to date”
- “Over 1 million views!”
Have fun testing your messaging and remember to use positive social proof to reinforce desired behaviours and actions. Check out this post to learn more about Cialdini’s 6 principles of influence.
