The anchoring bias occurs when people tend to rely too heavily on the first piece of information they see. 

The first price / value / thing that we see is anchored into memory and we then judge everything else based on that piece of information.


In 1974 Kahneman and Tversky recruited participants to spin a wheel of fortune that was rigged to stop on either 10 or 65.

When the arrow stopped, they asked the participants to say if they believed the percentage of African countries in the UN was higher or lower than the number on the wheel.

Next, they asked people to estimate what they thought the actual percentage was.

Even though the number on the wheel had no logical relevance to the actual answer, it influenced the participant’s responses:

So, people who landed on 10 guessed around 25%, and those who landed on 65 guessed around 45%. Their minds were anchored to that number of the wheel.


There are hundreds of biases in the world of behavioural science (even as self proclaimed experts in this field, there are too many for us to keep track of) but we have created a model that breaks down some of the most commonly and effectively used biases into six categories.

The anchoring bias falls under the Money category because this bias is typically used within pricing strategies or when indicating the value of something.


In Sharps Bedrooms TV ad we used the anchoring bias by first showing the audience the unappealing alternative to Sharps’ beautiful fitted wardrobes, which is its inadequate freestanding equivalent.

With items stacked on top and underneath, the audience can easily compare this untidy solution with Sharps’ fitted wardrobes, that merge stylishly with the bedroom’s design, leaving no unsightly clutter.

What the this means is that Sharps gives you twice as much storage space.

This campaign led to a significant increase in key metrics.


The anchoring bias helps us live healthier lives

A simple but effective example of anchoring is the “5 a day” push to get people to eat fruit and veg is a great example of this. ‘5’  has little scientific basis as the right amount to eat, but people have latched on to it.

5 a day, Change 4 Life, Anchoring
The 5 a day programme from Change 4 Life

The anchoring bias is commonplace in supermarket advertising

With aisles and aisles of brands to choose from it’s no surprise that for brands like ALDI, anchoring is a go-to behavioural bias for cutting through the competition.

Take ALDI’s ‘Like’ ads for example. They use price comparison to present brands with a higher price first. They do this to anchor the audience’s view on price before presenting the ALDI option, which is a much lower. Which do you choose?

Aldi Likes Brands, Anchoring,
From Aldi's "Aldi Like Brands" TV advert

What is Behavioural Science?

As consumers, we don’t think rationally, we think relatively. We don’t have any objective way of judging anything. So we compare based on an in built mental model.

The trouble is this mental model is often wrong.

Behavioural science allows us to control what you are compared against:

  • What triggers them to think of your category in the first place? And what comes to mind when they do?
  • What underlying motivation is driving their behaviour?
  • What factors will they use to compare you and your competitors?

To find out more about how our behavioural model makes marketing more effective, get in touch now.

By James Ballinger

Board Director

The Behavioural Bias Series