Common types of unconscious bias

Affinity bias: The tendency to warm to people who are more like us.

Halo effect: The tendency to only see the good about a person because of a personal affinity for the person; often described as ‘first impressions'. The opposite is the “horns effect” where a snap judgement is made based on a single negative trait.

Perception bias: The tendency to form stereotypes and assumptions about certain groups that can interfere with an objective assessment about individuals in those groups.

Confirmation bias: The tendency for people to seek information that confirms pre-existing beliefs or assumptions. This is an underlying tendency to notice, focus on, and provide greater credence to evidence that fits with our existing beliefs.

Conformity bias: The tendency people have to behave like those around them rather than using their own personal judgement. This type of bias often stems from seeking acceptance and validation from other people and from the need to hold views that are agreeable by the majority.

Gender bias: The tendency to prefer one gender over another.

Similarity bias: The tendency to form a favourable view of others who are similar to the decision-maker.

Distance bias: The tendency to prioritise input from people who are nearer in proximity/physical space, time or other domains, as opposed to people dialling in from remote locations.