Table of contents:


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


Behavioral 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 to increase in its price 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.[2] 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