At Peak Dynamics, we spend much time assessing and analysing judgement decision-making of individuals and teams, both in the corporate world, as well as with Elite Athletes and Extreme Adventurers.

In some of our more recent research, we have looked at the decision-making of football players in the English Premier Football League.

We wanted to understand better how apparent the decision-making bias was over the course of a football game. So we looked that the number of yellow cards issued over the season; split between the first half and second half; over the past ten years of the Premier League.

The bar chart shows that there is a more than a clear bias between both halves. What we do not know without further analysis is what exactly caused each of the offences. Some of the cards will undoubtedly be for professional fouls (where a player has deliberately fouled an opposition player), but what it does clearly show is that there is a bias between both halves. We would expect to see poor decisions starting to be made in the second half, as factors such as tiredness, stress and pressure to win start to appear.

We see this second half decision-making bias in other sports and pursuits. For instance, most deaths on Everest are on the way down and not on the way up the mountain. There is further research that shows there is a decision-making bias as hunger kicks in during different times of the working day.

Information is power. With the knowledge that a footballer is 50% more likely to receive a yellow card in the second half versus the first half, then the management team can develop a better strategy to prevent this. Likewise, in the office, depending on the time of day or week, management should be careful when critical decisions are made. Stress and tiredness can affect the skill of good decision-making.