Understanding different types of bias


In this section we will look at some of the different types of bias, at what the consequences of these can be in the workplace and at the ways to avoid them.


Affinity bias

Affinity bias can occur when we prefer people who share similar qualities to ourselves.

Affinity bias in the workplace

Affinity bias can sometimes be in play when an organisation recruits someone they like and know will get along with the team. Affinity bias can influence a recruitment decision when the decision is to recruit someone who shares similar interests, experiences and backgrounds to the recruiters. This does not necessarily help produce a diverse team that will bring in different ways of thinking and represent a wide range of viewpoints. While similarities should obviously never disqualify a candidate, they should not be the deciding factor either.

According to the NHS Workforce Race Equality Standard (WRES) Workforce Evaluation (2019), in 2016, in the average trust, white staff were 69% more likely than Black, Asian and Minority Ethnic staff to be appointed from a shortlist. While by 2018 this figure had improved and reduced to 56%, it is still high.

Ways to avoid affinity bias

Actively take note of the similarities you share with the candidate so that you can differentiate between attributes that may influence your judgement and the concrete skills, experiences and unique qualities that could contribute to your team as a ‘culture add’ rather than a ‘culture fit’.


Attribution bias

Attribution bias can sometimes be involved in the way that we understand and make sense of our own and other’s actions. People constantly make attributions – judgements and assumptions about why other people behave in certain ways. However, some attributions do not always accurately reflect reality and these attributions can introduce bias into decision-making.

Attribution bias in the workplace

During recruitment, attribution bias can be involved if recruiters make decisions about candidates where they attribute something unusual or potentially problematic about their application or behaviour as being an inherent feature of their personality or indeed of their gender, ethnicity or other ‘protected characteristic’. We might find attribution bias at play when an employee is treated differently because they do not approach a task in the same way as other people in the department and when this difference is negatively attributed to some ‘quality’ possessed by the employee.

Ways to avoid attribution bias

Do not rush your judgements. Take time to reflect on the assumptions you are making about people. Ask colleagues to outline and detail the reasons behind decisions they are proposing.  Give candidates or employees a chance to share their full story with you before making your judgements.


Beauty bias

Beauty bias can exist if we find that we prefer people we perceive as beautiful and if we are making judgements based on appearances and are judging others harshly based on their  appearance.

Beauty bias in the workplace

Professor Rachel Gordon from the University of Illinois in Chicago conducted some research into the connection between conventional physical attractiveness and the accumulation of social and human capital in young adults. One facet of the research indicated that conventionally ‘attractive’ people, both men and women, earn higher incomes, whereas ‘less attractive’ people earn lower incomes. This is perhaps also an example of attribution bias whereby ‘attractive’ people are viewed as more social, happy and successful.

Ways to avoid beauty bias

You should create structured recruiting and interviewing processes so that your team will be able to compare applications and interviews equally to reduce the risk of bias. Having an initial phone screening rather than a video call or in-person interview can also help as well as utilising carefully designed, explicit scoring measures to identify top candidates.


Conformity bias

Conformity bias can take place in situations where, in order to be accepted by a social group, people will tend to agree with the views of the majority within the group regardless of what they might think on an individual basis.

Conformity bias in the workplace

When your recruitment panel get together to review a candidate’s application and conduct an interview, conformity bias can cause individuals to sway their opinion of a candidate to match the opinion of the majority. The problem with conformity bias is that the majority is not always right, which may result in your team missing out on an excellent candidate because individual opinions become weakened in a group setting. Conformity bias can also take place where people agree with those individuals who have more power in a group. For example, in team meetings where one individual may hold the power and influence and others in the team feel some pressure to agree with the opinion of this powerful individual.

Ways to avoid conformity bias

Before a recruitment panel gets together to review a candidate, they could all write down their own opinion and submit this immediately after the interview ends. Then the panel could come together and review what everyone wrote down so that everybody’s independent opinions can be seen and heard. In a team meeting situation, ensure everyone’s opinions are encouraged and invited and are considered. Use technology to collect opinions anonymously.


Confirmation bias

Confirmation bias can happen when we look for, or give greater weight to, evidence that confirms our views and experiences. This can lead to selective observation and us not seeing or valuing evidence that contradicts our beliefs.

Confirmation bias in the workplace

Confirmation bias can play a role at the very beginning of the recruitment process when you first review an application form and you form an initial opinion of the candidate based on attributes like where they’re from, where they went to school or university, or if they have a similar interest to you etc. This opinion you have of the candidate can follow you into the interview process and consequently steer questions to confirm the initial opinion you had of the candidate. This kind of effect can follow the candidate all the way through their career within an organisation, with them being treated more favourably, thus making it easier for them to be successful. Confirmation bias is an example of a bias that is based on ‘culture fit’. According to the Harvard Project Implicit study, black people are more likely to face scrutiny over performance and ‘culture fit’.

Ways to avoid confirmation bias

While every interview will lend itself to a unique conversation based on the individual’s background, it’s important to ask standardised skills-based questions that provide each candidate with a fair chance to stand out. This will help prevent your team from asking too many off-the-cuff questions that may lead to confirmation bias.

Give everyone in the organisation an equal opportunity to progress with equal access to good coaching and mentoring, not just certain people who share your opinions and experiences. Consider opportunities equally for black and ethnic minority staff. They should not feel like they have a once in a lifetime chance to prove themselves and that if it goes wrong there won’t be another. Give them the treatment you should give to all staff so that they have chances to learn and improve and progress.


Gender bias

Gender bias, as the term suggests, occurs where decisions are based on a preference for a particular gender, often based on stereotypes and deep-seated beliefs about gender roles.

Gender bias in the workplace

Gender bias is at play when one gender is given preferential treatment over another in the recruitment process or in the workplace. An example of this is when it was reported that ten NHS organisations in England had a median hourly pay gap that favoured men, with the gap ranging from 0.1% of median hourly pay to 52.5%. According to Harvard Business School women don’t apply for jobs that they are not 100% qualified for but men are more likely to apply for jobs that they are not qualified for. According to this research, women apply for jobs when they meet 100% of the criteria, while men apply if they meet just 60%. The Harvard Business School survey also found that women tend to get less credit for success and more blame for failure and that 49% of women felt disadvantaged in their career due to their gender as opposed to 4% of men.

Ways to avoid gender bias

Conduct blind screenings of applications that exclude aspects of a candidate that may reveal their assumed gender, like name and interests. Set diversity recruitment goals to ensure your company holds itself accountable to equitable recruitment practices. And again, make sure to compare candidates based on skill and merit rather than traits that can cloud your judgement of them.


The halo effect

The halo effect can introduce bias into decision-making when you focus solely on one great feature about an individual and ignore everything else.

The halo effect in the workplace

The halo effect can come into play at any stage of the recruitment process. For example, it could be in play when you see a candidate who may have worked at a highly-regarded company or may have graduated from a certain university and you judge the candidate heavily on the merit of their university or past place of work rather than their skills or other aspects of their application.

Ways to avoid the halo effect

The halo effect can be dangerously blinding when it comes to reviewing candidates. When reviewing a stack of applications, you are probably looking for something unique that makes a candidate stand out from the rest. When you do this, also consider the candidate without that one gleaming attribute and who may not have had the same privileges or opportunities as other candidates and think about how their experiences, skills and personalities combine together compared to other candidates.


The contrast effect

The contrast effect can introduce bias when judgements are made based on a comparison between people rather than assessing people individually on their own merits.

The contrast effect in the workplace

This is one of the most common types of bias in the recruitment process. When you’re reviewing loads of candidates, it can be easy to compare one application to the next in the stack and therefore not see the individual merits of applications. Similarly, an exceptionally good interview with one candidate may make it harder for recruiters to judge the very next candidate with fresh, fair independent eyes.

Ways to avoid the contrast effect

Create the application review and interview processes so that individual judgements against structured criteria have to be explicitly made, so that interviewers are not making judgements and scoring candidates on impressions. A similar approach should also be taken for performance reviews and rewards for individual employees to remove impressionistic decision-making from those processes.



Ageism is when is an individual is negatively discriminated against because of their age.

Ageism in the workplace

Ageism can affect both young and older people. It can sometimes be more difficult for individuals to change careers later on in life as recruiters may want new talent and not want to recruit someone who is older. That would be one example of ageism at work. At the same time, younger people might be suitably qualified but find it hard to get a senior role because they look too young or are assumed not to be capable of a role because of their age.

Ways to avoid ageism

Train your recruitment team members to understand the issue of ageism and keep age diversity at the top of your mind when recruiting new talent.


Name bias

A name bias occurs is when an individual is negatively discriminated against because of their name.

Name bias in the workplace

Name bias can exist in the recruitment process. For example, a field experiment in the US by Marianne Bertrand and Sendhil Mullainathan, where they submitted fictitious CVs to wanted ads, where each resume was assigned either a very African American sounding name or a very white sounding name, found that white names receive 50% more call-backs for interviews than African American names. The Harvard Project Implicit study also found that replacing an ‘international’ name with an English name increased candidates’ chances of being hired.

Ways to avoid name bias

Omit the candidate’s name and personal information from the application information that is reviewed by the recruitment team at the shortlisting stage. This will ensure that the recruitment team is selecting candidates based on their skills and experiences without the influence of irrelevant personal information.