Micromorts and Understanding the Probability of Death

Under­stand­ing prob­ab­il­it­ies is hard (viz.) – and it’s espe­cially so when we try to under­stand and take ration­al decisions based on very small prob­ab­il­it­ies, such as one-in-a mil­lion chance events. How, then, to com­mu­nic­ate risks on a sim­il­ar level, too?

The answer is to use a more under­stand­able scale, such as micro­morts; “a unit of risk meas­ur­ing a one-in-a-mil­lion prob­ab­il­ity of death”. Some activ­it­ies that increase your risk of death by one micro­mort (accord­ing to, among oth­er sources, the Wiki­pe­dia entry):

  • smoking 1.4 cigar­ettes (can­cer, heart dis­ease)
  • drink­ing 0.5 liter of wine (cir­rhosis of the liv­er)
  • liv­ing 2 days in New York or Boston (air pol­lu­tion)
  • liv­ing 2 months in Den­ver (can­cer from cos­mic radi­ation)
  • liv­ing 2 months with a smoker (can­cer, heart dis­ease)
  • liv­ing 150 years with­in 20 miles of a nuc­le­ar power plant (can­cer from radi­ation)
  • drink­ing Miami water for 1 year (can­cer from chlo­ro­form)
  • eat­ing 100 char­coal-broiled steaks (can­cer from ben­zo­pyrene)
  • eat­ing 40 table­spoons of pea­nut but­ter (liv­er can­cer from Aflatox­in B)
  • eat­ing 1000 bana­nas, (can­cer from radio­act­ive 1 kBED of Potassi­um-40)
  • trav­el­ling 6 miles (10 km) by motor­bike (acci­dent)
  • trav­el­ling 16 miles (26 km) on foot (acci­dent)
  • trav­el­ling 20 miles (32 km) by bike (acci­dent)
  • trav­el­ling 230 miles (370 km) by car (acci­dent)
  • trav­el­ling 6000 miles (9656 km) by train (acci­dent)
  • fly­ing 1000 miles (1609 km) by jet (acci­dent)
  • fly­ing 6000 miles (9656 km) by jet (can­cer from cos­mic radi­ation)
  • tak­ing 1 ecstasy tab­let

Issue fifty-five of Plus magazine looked at micro­morts in more detail, thanks to Dav­id Spiegel­hal­ter (the Win­ton Pro­fess­or of the Pub­lic Under­stand­ing of Risk at the Uni­ver­sity of Cam­bridge) and Mike Pear­son, both of Under­stand­ing Uncer­tainty.

via Schnei­er on Secur­ity