RISKOMETER

It all started out so helpfully. Dr Frank Duckworth of the Royal Statistical Society (who with Tony Lewis invented the cricket scoring system now in use in Britain) knew that people found it extremely difficult to judge relative risks. So at the RSS annual conference last week he presented a scale, similar to the Richter scale for earthquakes, designed to make the risk of various activities more obvious. This has been described as a riskometer, a term which has been independently invented by several people down the years in other contexts. Level 0 in the scale is safety, at least to the extent of surviving for a year; you reach Level 8 by playing Russian Roulette with every chamber of the gun filled (a dead certainty, as you might say). What he didn’t allow for was the inability of people to understand the logarithmic scale involved (thus making Level 4, for example, seem too close to Level 6); nor did he expect vilification from so many women, who pointed out that most of his examples were male activities such as rock-climbing or deep-sea fishing (At the risk of seeming sexist, I must say that he did provide some estimates of household chores, such as dying while washing up or vacuuming — these have a risk factor of 5.5.)

Perhaps the Society should consider initiating a debate about the need for appropriate forms of national “riskometer”, to provide easily understood operational guidance to the public about everyday risks, and to enable new risks as they arise to be calibrated against familiar ones.

Professor Adrian Smith, Address of the President to
The Royal Statistical Society, 12 June 1996

The riskometer originated from a call by an ex-RSS president for a scale to help the public grapple with bafflingly big figures and Whitehall evasions like “a small but significantly raised risk”.

Guardian, July 1999

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