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Noise: A Flaw in Human Judgment

What the book does

Kahneman, Sibony and Sunstein define noise as unwanted variability in professional judgement, distinct from bias, and set out to measure it. Drawing on studies of judicial sentencing, insurance underwriting, medical diagnosis, forensic science, recruitment and forecasting, they identify where such variability comes from and describe the procedures used to reduce it. 

What it changes in practice

The authors provide practical steps and protocols to help reduce noise. These include asking directors to record brief written opinions before an open discussion, preventing the board from anchoring on the first confident voice, and inviting the newest director to speak first. For major decisions, they recommend the Mediating Assessments Protocol: define the relevant factors at the outset, assess each one independently, and delay the overall decision until the end.

Why I recommend it

The quality of any board is primarily measured by the quality of its decision making. Understanding how bias and noise creep into decision making processes is key in understanding how we can improve. Noise gave me practical tools which I was able to put into practice when moving into a sub-committee chair role.

The Mediating Assessment protocol is particularly helpful for structuring hiring decisions. By assessing the individual criteria before forming an overall view, it helps prevent early intuition from influencing how the evidence in a scorecard is interpreted. I have since used this approach in hiring discussions and found it a useful discipline for making the conversation more evidence-based.

There is an important caveat for boards. These methods used to measure noise were built for high volume, comparable and repeated decisions. Boards typically make fewer, often unique, decisions, so we may not be able to measure our noise accurately. But we can learn to recognise where it enters our decision-making, and put disciplines in place to reduce it. For me, that is where the real value of the book lies.

Who it suits

Noise is especially suited to NEDs moving into a chair role. It sharpens awareness of bias and inconsistency that can affect collective judgement, and offers practical ways to improve the quality and reliability of decision-making.  

Tom Noel, NEDness Co-Founder and Chief Commercial Officer

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