Measuring lethality in reduced expected heartbeats

by chaosmage 1 min read3rd Jan 201427 comments


Some of us here are already familiar with Micromorts - a unit that stands for a 1 in a million chance of dying. The wikipedia page lists a number of sample values. One obvious example is that smoking 1.4 cigarettes is one micromort. This is a good tool for comparing the relative dangerousness of activites - for example, if you fly in a jet in the US, your micromorts per mile from increased background radiation are twice the micromorts per mile from terrorism. And you can compare activities to baseline average risks of death, given as about 39 per day (averaged over all age groups and sexes).

However, people suck at imagining small probabilities. So a different unit, which we used in a group exercise at the Secular Solstice in Leipzig, is the number of expected future heartbeats. While Micromorts are a step away from empirical reality, expected heartbeats are another step in the same direction. But the concept got good feedback, it makes people think about life in a new way, so I thought I'd just share it here.

The average human heart gets to beat about 2.5 billion times - about 100000 times per day. So a micromort is around 2500 expected heartbeats. So you can translate, say, smoking a cigarette into a cost of about 1800 expected heartbeats (or about 80 seconds of life expectancy). And maybe that'll help people optimize their behavior in ways that Micromorts, due to their microprobability nature, aren't very good at doing especially for those who aren't very habitual Bayesians.