Micromort
A micromort is a unit of risk measuring a one-in-a-million probability of death (from micro- and mortality). Micromorts can be used to measure riskiness of various day-to-day activities. A microprobability is a one-in-a million chance of some event; thus a micromort is the microprobability of death. The micromort concept was introduced by Ronald A. Howard who pioneered the modern practice of decision analysis.[1]
Human values
Money
An application of micromorts is measuring the value that humans place on risk: for example, one can consider the amount of money one would have to pay a person to get him or her to accept a one-in-a-million chance of death (or conversely the amount that someone might be willing to pay to avoid a one-in-a-million chance of death). When put thus, people claim a high number but when inferred from their day-to-day actions (e.g., how much they are willing to pay for safety features on cars) a typical value is around $50 (in 2009).[2][3]
Baseline
The average risk of dying per day can be calculated from the average lifetime. Assuming this is 70 years, that means there is one death for every 25,550 days lived (70 x 365 = 25,550).
The number of micromorts per day is one million divided by that number of days; in this case, about 39 micromorts acquired individually every day. The number of micromorts per hour is divided by 24 hours; that is about 1.63 micromorts per hour. This is just an average across an entire population: the number of micromorts per day will vary across different categories of people, such as by age, sex and lifestyle.
An alternative way of getting the same figure is to take the number of people dying each day in the UK (about 2500), and divide it by the total population (60 million). These figures include all deaths. When natural deaths are excluded, the result measures the risk of premature death, which is roughly one micromort per day. In the UK, approximately 50 people die each day, on average, from non-natural causes [4].
Additional
Activities that increase the death risk by one micromort, and their associated cause of death:
- smoking 1.4 cigarettes (cancer, heart disease)[5]
- drinking 0.5 liter of wine (cirrhosis of the liver)[5]
- spending 1 hour in a coal mine (black lung disease)[5]
- spending 3 hours in a coal mine (accident)[5]
- living 2 days in New York or Boston (air pollution)[5]
- living 2 months in Denver (cancer from cosmic radiation)[5]
- living 2 months with a smoker (cancer, heart disease)[5]
- drinking Miami water for 1 year (cancer from chloroform)[5]
- living 5 years at the boundary of a nuclear power plant (cancer from radiation)[5]
- living 150 years within 20 miles of a nuclear power plant (cancer from radiation)[5]
- eating 100 charcoal-broiled steaks (cancer from benzopyrene)[5]
- eating 40 tablespoons of peanut butter (liver cancer from Aflatoxin B)[5]
- eating 1000 bananas, (cancer from radioactive 1 kBED of Potassium-40)
- travelling 6 minutes by canoe (accident)[5]
- travelling 6 miles by motorbike (accident)[6]
- travelling 17 miles by walking (accident)[7]
- travelling 10 miles[5] (or 20 miles[7]) by bicycle (accident)
- travelling 230 miles (370 km) by car (accident)[6] (or 250 miles[7])
- travelling 6000 miles (9656 km) by train (accident)[6]
- flying 1000 miles (1609 km) by jet (accident)[5]
- flying 6000 miles (9656 km) by jet (cancer from cosmic radiation)[5]
- receiving one 10mrem chest X-ray in a good hospital (cancer from radiation)[8]
- taking 1 ecstasy tablet[6]
Increase in death risk for other activities on a per event basis:
See also
References
- ^ Howard, R. A. (1980). "On making life and death decisions". In J. Richard, C. Schwing, Walter A. Albers. Societal Risk Assessment: How Safe Is Safe Enough? General Motors Research Laboratories. New York: Plenum Press. ISBN 0306405547.
- ^ Howard, R. A. (1989). "Microrisks for Medical Decision Analysis". International Journal of Technology Assessment in Health Care 5 (3): 357–370. doi:10.1017/S026646230000742X. PMID 10295520.
- ^ Russell, Stuart; Norvig, Peter (2009). Artificial Intelligence (3rd ed.). Prentice Hall. p. 616. ISBN 0136042597.
- ^ ONS Mortality statistics [1], UK Office of National Statistics 2009, ISSN 1757–1375, accessed 2010-12-08
- ^ a b c d e f g h i j k l m n o p * Howard, Ron Risky Decisions (Slide show), Stanford University
- ^ a b c d e Spiegelhalter, David (10 February 2009). "230 miles in a car equates to one micromort: The agony and Ecstasy of risk-taking". The Times (London). http://www.timesonline.co.uk/tol/comment/columnists/guest_contributors/article5696688.ece. Retrieved 19 April 2009.
- ^ a b c Understanding Certainty
- ^ "Radiation and Risk". Idaho State University. http://www.physics.isu.edu/radinf/risk.htm. Retrieved 2011-03-16.
- ^ http://alertdiver.com/349
- ^ http://www.skydivingmagazine.com/faq.htm
Further reading