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Web psychology: Cognitive biases & behaviour patterns for conversion optimisation.

From A to Z: Psychological principles & cognitive biases to consider when a/b testing your websites.

Cognitive... behavioural ... what?

We like to think that we are in control of our conscious decisions.

Most of the time, we are not.

The human brain is a lazy thing. And it is amazing at finding shortcuts. These shortcuts often appear as repeatable behavioural patterns, and cognitive biases – principles that we are often not aware of, and that impact our decisions heavily. Most of the time they are solely based on emotional factors.

With some knowledge about these psychological effects, you can use them for optimising your sales & marketing assets, and improving the outcome of your website a/b testing efforts.
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Anchoring effect

People rely too much on pre-existing information or the first information they find.

Anchoring or focalism is a cognitive bias where an individual depends too heavily on an initial piece of information offered (considered to be the “anchor”) when making decisions. Source

Authority bias

People are easily influenced by authorities.

The tendency to attribute greater accuracy to the opinion of an authority figure (unrelated to its content) and be more influenced by that opinion. Source

Behavioural momentum

When people love your old website too much.

Behavioral momentum is a metaphor based on physical momentum. It describes the general relation between resistance to change and the rate of reinforcement obtained in a given situation. Source

Commitment & consistency bias

People want to be – and appear – consistent with what they have already done.

If people commit, verbally or in writing, to an idea or goal, they are more likely to honor that commitment. Even if the original incentive or motivation is removed after they have already agreed, they will continue to honor the agreement. Source

Cross(-price) elasticity of demand

The price of product A impacts the demand of product B.

The cross elasticity of demand or cross-price elasticity of demand measures the responsiveness of the quantity demanded for a good to a change in the price of another good. Source

Decoy effect

People's preference for one option over another changes when adding a third (similar but less attractive) option.

In marketing, the decoy effect (or attraction effect or asymmetric dominance effect) is the phenomenon whereby consumers will tend to have a specific change in preference between two options when also presented with a third option that is asymmetrically dominated. Source

Framing effect

People’s choices are influenced by the way they are framed through different wordings, settings, and situations.

The framing effect is a cognitive bias where people decide on options based on whether the options are presented with positive or negative connotations; e.g. as a loss or as a gain. Source

Halo effect / horn effect

A positive trait can positively influence people’s thoughts and feelings about other traits.

The tendency for positive impressions of a person, company, brand or product in one area to positively influence one’s opinion or feelings in other areas. Source

The horn effect is similar, but with negative traits influencing negatively.

Price elasticity of demand

The price impacts the demand of a product.

Price elasticity of demand is a measure to show the responsiveness, or elasticity, of the quantity demanded of a good or service when nothing but the price changes. Source

Serial-position effect / primacy & recency effect

People tend to remember the first and last thing mentioned.

The serial-position effect is the tendency of a person to recall the first and last items in a series best, and the middle items worst.

The primacy effect, in psychology and sociology, is a cognitive bias that results in a subject recalling primary information presented better than information presented later on.

The recency effect suggests that items listed last are retrieved from a highly accessible short-term buffer, i.e. the short-term store (STS) in human memory. Source

Reciprocity bias

People feel obliged to return favours.

In social psychology, reciprocity is a social norm of responding to a positive action with another positive action, rewarding kind actions.

As a social construct, reciprocity means that in response to friendly actions, people are frequently much nicer and much more cooperative than predicted by the self-interest model; conversely, in response to hostile actions they are frequently much more nasty and even brutal. Source

Scarcity bias

People want more of those things they can have less of.

The scarcity heuristic is a mental shortcut that places a value on an item based on how easily it might be lost, especially to competitors.

The scarcity heuristic stems from the idea that the more difficult it is to acquire an item the more value that item has. In many situations we use an item’s availability, its perceived abundance, to quickly estimate quality and/or utility. This can lead to systemic errors or cognitive bias. Source

Social proof

If others like or use this, it can’t be bad.

People generally look to other people similar to themselves when making decisions. This is particularly noticeable in situations of uncertainty or ambiguity. Source