Can you imagine a scenario where you were asked a question and you chose the obviously wrong answer, just because the others did the same?

Actually, it can happen to you, as well. 75% of the people who participated in Solomon Asch’s 1951 conformity experiment chose the obviously wrong answer at least once during the test.
By hiring actors, he was able to apply peer pressure to the subjects and increase the number of wrong answers from 3% (control group) to 32%, which is quite impressive.

This is what people call the effect of social proof.

Imagine the influence of it under another condition, where the right choice isn’t that obvious… For example, if you’re not sure whether the joke you’ve heard in a sitcom is funny or not.
And then you hear the invisible guys laughing on it in the background. And you automatically start to appreciate the joke that was – originally – mediocre at most.

And this is exactly the same reason why testimonials and reviews also have influence on you: because you are constantly observing what others do. Actually, that’s what you and I have been doing from the moment we were born.
By imitating each other, we learn basic and more advanced skills required in order to survive.

Are we doing it on a conscious level? Sometimes, yes, but as you can see by reading this blog, most of the factors that have influence on your decisions are subconscious. These are shortcuts that we learnt and/or inherited in order to make fast decisions, or decisions at all.
Social proof included.

It is also true for animals. Basically, if you give a rat a marked food to eat, and let another one observe this ritual, then it will prefer the marked food versus a non-marked food. This is completely rational: if the other didn’t die by eating the marked food, why would you want to risk your life taking the other, untested one? (This behavior is called “Socially transmitted preference for food” and if you give it a thought, you will recognize its similarity with advertising.)

The effect of social proof is so extraordinary, that there is even a National Social Norms Institute, where people create public campaigns using only this tool. If you browse through their case studies, you can easily realize how effective their efforts are: they can easily reduce alcohol and tobacco consumption by 30% by stating simply that “Most of us (81%) don’t use tobacco”.

Ridiculously effective and ugly posters

This method should be used if you want to reduce tax evasion, and the only tool you have is a letter you can attach to the tax form. In this case, you should underline the fact that the majority of the taxpayers do not cheat on their tax return.
Also, it can be used in therapies. For example, if your child is afraid of dog, you can help him or her to overcome the fear by watching movies with him, where kids are frequently playing with animals… And that’s coming from an actual study that was conducted by the researcher Robert O’Connor (1972).

On the web, review sites are leveraging our need to gain information about what others think and do. And these sites really have an effect. For example, a one-star rating increase on Yelp (a popular online review site for local services) leads to 5-9% growth in revenue.
However, the same is not necessarily true for IMDB, but for a different reason.

The funny thing is that you can increase the appeal of anything even by making a non-direct suggestion for its popularity. For example, if you write something like “Although we’re flooded with emails, we are trying our best to answer each and every message on time.” on your website, you will notice that more people will write to you.

Okay, I want to show you something. Please have a look at the two pictures below:
Which one do you find more appealing?

So I think you noticed that if your friends “liked” a particular site, you are more persuaded to click on the same button. It’s not a secret: social proof works best if it’s personalized. If you see your friends drinking a new brand of beer, that definitely has more influence on you than watching hundreds of unknowns doing the same (Park, 2001; Stangor et al, 2001).
And we reached the second most important factor that influences the effectiveness of social proof: the quantity. This is true even in a completely artificial environment. It sounds hilarious, but even if you hear five product reviews read by five different synthesised (!) voices instead of one, that would influence you more! (Lee, 2004)
This is the so-called multiple source effect.

Displaying social proof elements on your website is beneficial both for you and your visitors. Actually, there is a cause and effect relationship between the two: It is good for you, because it is beneficial for the popular users on your site, therefore they will spend more time there and attract more people. And the circle keeps repeating itself, which can lead to viral growth in no time.

Nowadays a new way of “acquiring” social proof emerged. I’m talking about the “pay with a tweet” phenomenon. Honestly, I don’t think it is a good idea.
Forcing your users to share your ad or content can lead to rapid growth, something what Zynga experienced a few years ago.
If you are not in the casual-gaming business, but trying to acquire more high-profile users, this method can also be counter-productive. Opinion leaders are well known by their choosiness and they will only promote your brand if your product or service is really good.
And in this case, there’s no need to force them. They will recommend you to others happily, that’s what opinion leaders are known for!

There’s the other side of the coin… Let’s look at my blog.
If you can’t believe your intuition which says that this is a good article, you will look at the number of likes and tweets it has. And if the counter shows a small number of shares, you will be less likely to value it, unfortunately.
But remember, you’re one of the first ones who has read this post, so if that’s really the case, please ignore them and/or click on one of those buttons, if you feel like it!

Ps.: Did you notice that by listing the name of the researchers in brackets, I am using a special kind of social proof to convince you about my point?