Use cognitive biases in CRO

1. Repost your message, story, and copy on your website and social media to generate positive conversation around your product and brand.

Place calls to action throughout your landing pages, pay to retarget your visitors with ads, post regularly on social media, and guest blog so that your potential customers are repeatedly exposed to your message. Repetition of your key messages, story, and copy uses attentional bias – the tendency of our perception to be affected by our recurring thoughts – to increase the likelihood of purchase. The more people positively talk about your site, the more likely they are to purchase from you.

2. Use scarcity and social proof to encourage customers to buy your product.

Seed your product or service in a niche community to create a group mentality within that niche. Add social proof in the form of numbers and testimonials near points of friction like the checkout page, to encourage customers to complete their purchase. The bandwagon effect is the tendency to do or believe things because many other people do or believe the same. If your visitor thinks that everyone else is using your product, they are more likely to buy it.

3. Calculate the correct sample size using Evan Miller's tool before starting a test.

The clustering illusion is the tendency to overestimate the importance of small runs, streaks, or clusters in large samples of random data. You can develop a false belief that there is a trend, and create future tests and hypotheses based on false information. Avoid this by using the correct sample size – one that is representative of your sample – and continuing the test until you have reached it. You can calculate sample size using Evan Miller’s Sample Size Calculator. In this case, we told the tool that we have a 3% conversion rate, and want to detect at least 10% uplift. The tool tells us that we need 51,486 visitors per variation before can look at the statistical significance levels and statistical power.

4. Search for and understand information that disagrees with your existing beliefs.

Confirmation bias is the tendency to search for, interpret, focus on, and remember information in a way that confirms one’s preconceptions. For example, if you believe that reducing form fields increases conversions and your test marginally supports the belief, you’ll likely call the test a success and move on – missing valuable insights and neglecting more significant tests. Before you run a test, try to eliminate any emotional attachment to a result. Your visitors also have preconceptions which are difficult to change. Cater to those preconceptions through familiarity and consistency, instead of trying to alter them straight away.

5. Describe your product or service using simple language that the customer can understand.

The curse of knowledge refers to experts finding it difficult to think about problems from the perspective of lesser-informed people. You can accidentally use language or design that customers do not understand. Conduct qualitative research to discover how current customers describe your product or service. Then use the same language to describe your product. Alternatively, ask someone who’s new to the industry to craft your messaging or help you redesign to increase conversions.

6. Craft emotional copy, offer emotional context, use emotional design/UX, and create an emotionally persuasive call to action.

The empathy gap is the tendency to underestimate the influence or strength of feelings in yourself or others. Conduct qualitative research to understand the emotions associated with your site and brand, then design emotionally persuasive arguments based on that information. Context is important if you are trying to play on visitors’ past memories or behaviors. Those feelings are easier to recall when they are in the same context as they were previously. Use your copy, keywords, and design to set the stage and make it easier for the user to retrieve those feelings, memories, and behaviors.

7. Present and reinforce your value proposition in a way that resonates with your customers.

The framing effect describes our tendency to draw different conclusions from the same information, depending on how that information is presented. When deciding how to present your value proposition, ask: Will you use data to persuade? Will you ask questions to inspire deep thinking? Will you tell a story? Aim to guide every visitor to the same conclusion. In your post-purchase messaging, use positive words that signal a successful purchase and reinforce the value proposition.

8. Eliminate unnecessary form fields, simplify the language, and make the site designs intuitive to support your customer in completing their purchase.

Unit bias is the tendency to want to finish a given unit of a task or an item. Your visitors want to finish the purchase that they have started. Structure your copy to include a beginning, a middle, and an end to improve readability and time-on-page. Go through your conversion funnel and ask yourself: Are there steps that make completion more difficult than it needs to be?

9. Consider external factors that could influence your test before coming to conclusions about your data.

Illusory correlation is when you inaccurately perceive a relationship between two unrelated events. This can impact your test results and your ability to analyze and report them accurately. Consider factors – like holidays, new paid campaigns, and the day of the week – that could influence your test. Check that your test has reached statistical significance with the appropriate sample size so that its results are valid.

10. Create contrast using surprising elements so that your website stands out.