Most people believe they are less biased than their peers according to researchers, led by an academic from Cass Business School. This systematic tendency to overrate our own impartiality has been termed ‘the bias blind spot’.

The research, published in the journal Management Science, looked at the pervasiveness of the bias blind spot and the effects it can have on an individual’s decision making.

Dr Irene Scopelliti, a lecturer in marketing at Cass Business School, City University London and the lead author of the study says;

“We developed a questionnaire to measure to what extent people think they are less biased than others on a variety of decision making biases and observed that surprisingly only one participant out of 661 reported to be more biased than the average person.

“But people who think they are less biased than others are not actually smarter than others, nor they are less smart: The bias blind spot appears to be a unique construct. It is independent of intelligence and personality traits related to self-esteem, self-enhancement, and self-presentation.”

Why does the bias blind spot matter, and how might it affect businesses in real terms?

Firstly, the bias blind spot determines how accurately we measure our own abilities. Research has shown that when people evaluate their own abilities in comparison to others, they tend to think they are better than average in their ability to perform easy activities (e.g. using a computer mouse) but worse than average with more difficult activities (e.g. juggling).

Scopelliti and colleagues from Boston University, Carnegie Mellon University and the University of Colorado, found that the higher in bias blind spot people are, the less accurate they are at evaluating their own ability in comparison to others.

Secondly, the bias blind spot affects how likely we are to accept advice. Considerable research has found that integrating advice from others into our own judgments generally improves the quality of our decision-making. However, participants with a greater bias blind spot were more likely to ignore advice, and were significantly less likely to revise their own evaluations based on another’s input.

Lastly, the bias blind spot has an impact on the effectiveness of practices aimed at improving decisions and reducing bias within societies and organisations. The study revealed that those with a higher bias blind spot score were less affected by training procedures, and therefore were least likely to improve the quality of their decisions.

Scopelliti says:

“Our research found that the extent to which one is blind to their own bias has important consequences for the quality of decision making. The bias blind spot is a strong barrier that keeps people from improving their decision making. People more prone to think they are less biased than others are less accurate at evaluating their abilities relative to others, they listen less to advice, and are less likely to learn from training that would help them make less biased judgments.”