Emma Peardon

What is similarity bias, and why does it matter?


Leaders are put in place to build the most efficient, productive team possible. However, even the very best recruiters can fall foul of unconscious bias – that is, making a decision based on a feeling one isn’t even aware of.

What is similarity bias?

In recruitment, similarity bias is when a manager hires a candidate based upon their own image, no matter how tenuous the link may seem. For example, the hiring manager may inadvertently give the green light to a candidate who went to the same university, has similar interests, or even the same ethnicity as themselves.

Similarity bias refers to when a manager hires a candidate based upon their own image, no matter how tenuous the link may seem.

“We like people who somehow resemble us more and who we can see ourselves in,” says Michelle Stratemeyer, a diversity and inclusion academic at the University of Melbourne. Also known as ‘affinity bias’, the phenomenon is rife among Australian recruitment, with Diversity Australia discovering that this particular bias has been the overriding factor in 78 per cent of recruitment decisions.

How does similarity bias impact businesses?

Hiring with unchecked similarity bias can have a hugely detrimental effect on workplaces, because it snuffs out any diversity – and that spells bad news for any business.

A report produced by McKinsey found that organisations with a diverse workforce are more likely to see above-average profitability. Additionally, employees in inclusive teams are 10 times more likely to be highly effective, and nine times more likely to innovate, states a study published by the Diversity Council of Australia.

Is similarity bias part of your interviewing technique?Similarity bias is creeping into the hiring cycle of many onboarding professionals.

So how can you guard against similarity bias when recruiting? There are a couple of methods HR professionals can put in place when moving through the hiring process:

Two ways to minimise similarity bias

1. Stick to a set of standard questions

Using a pre-determined set of questions can help fend off any similarity bias that might creep in. Stay away from any questions about social background, favoured sports teams, and even interests outside of work.

Even though such questions might be well-intentioned, or perhaps be intended as icebreakers, they can trigger a range of unconscious bias. Asking the same set of questions to each candidate can help eradicate this. One study, published in Personnel Psychology, found that well-structured interviews, with preset questions, largely eliminated unconscious racial bias in the final hiring decision.

2. Blind CVs 

A blind CV is simply one that has had the candidate’s name removed, and even the university that they attended. The idea is that the recruiter won’t disregard applications out of hand due to cultural, academic or gender bias – it will simply come down to the quality and suitability of the person on the page.

It’s important that organisations continue to adjust to societal trends involving ethnicity and gender, among others. This will help ensure that the workforce is sufficiently diverse, which in turn will encourage a melting pot of new ideas, fresh viewpoints and progressive thinking within the workplace – and that can only mean good news as for Australian business.