The action bias describes our tendency to favor action over inaction.

However, there are times when we feel compelled to act, even if there’s no evidence that it will lead to a better outcome than doing nothing would. Our tendency to respond with action as a default, automatic reaction, even without solid rationale to support it, has been termed the action bias.

The hysterical response from most of the World Governments to the Covid-19 pandemia is an evident phenomenon, featured by measures not supported by solid rational nor evidence, but just driven by the feeling that inaction might be worse. In fact, in situations where the correct decision is unclear, our automatic response tends to be based in action, ignoring the potential benefits of inaction.

A study by Bar-Eli et al. (2007) has analyzed how the action bias works. In soccer, when a penalty is awarded, it will a contest among the keeper and goal keeper.

The authors examined penalty kicks from top leagues and championships world wide, and 311 suck kicks were found. A panel of three independent judges was used to analyze the direction of the kick and the direction of the movement by the goalkeeper.

The kicks were equally distributed with one third of the kicks aimed to the left, one third aimed to the right and one third to the left of the goal mouth.

However the, the goalkeepers displayed a distinct action bias: they either dive left or right 94% of the time, hardly ever choosing to remain in the middle of their goal mouth.

The researchers, then, calculated the success rate from the combinations of kicks and jumps. The best strategy was when the goalkeeper stayed in the centre of the goal mouth: he saved 60% of the kicks aimed to the centre, far higher than his saving rate when he dived either left or right (30%).

However, far from following the optimal strategy of the centre, goalkeepers would stay in the centre just 6.3% of the time!

The action bias, displayed by the keepers, is clearly a suboptimal behavior patten.

The reason for this action bias seems is related to the feeling of effort, that the goalkeeper feel when he dives left or right (the feeling of doing something). Standing in the centre and watching a goad scored to the left or to the right of him, he would feel much worse!!

The action bias is even more evident in the field in investment and trading. Because the investor would forget that inaction is also a decision. As Paul Samuelson once opined “Investing should be dull. It should not be exciting. Investing should be more like watching paint dry or watching grass grow”. If you want excitement, take $800 dollars and go to Las Vegas”.

The action bias regularly manifests in the health sector, specifically, when it comes to treating patients with unusual symptom presentations that doesn’t seem to require urgent care. It’s been shown that, if there’s no clear diagnosis, the majority of doctors prefer to run tests to attempt to find the root of the problem, rather than schedule a follow-up to see if symptoms have changed. The inaction bias in medicine leads to Overdiagnosis and Overtreament, magnifying the field of Incidentalomas.