http://stats.org/stories/2011/value_statistical_life_jun27_11.html
Where VSL numbers come from
Ultimately, such analysis can be used to generate a number in dollars for VSL, using something called the standard wage equation. In their meta-analysis of wage-risk studies, Janusz Mrozek and Laura Taylor give a straightforward explanation of the math behind the numbers. The wage equation is a statistical estimate of the breakdown of wages due to a worker's profile. Variables in the equation account for demographic factors like age and education level, and job characteristics like risk of injury, as well as overall risk of death on the job. VSL is computed as the rate of change of a worker's wage with respect to the change in risk of death.
For example, suppose that the increased risk of death on a job is 1 in 10,000 compared to a job with no observable job-related death, and that a worker is paid an additional $0.35 per hour for accepting this risk. Assume the worker works 2,000 hours per year (40 hours per week times 50 weeks), so that $0.35 x 2,000 = $700 per year in wages is paid to the worker for death risk. Since the expectation is that 10,000 people would be paid this additional $700 per year in wages per one death, the statistical value of life is given by the total marginal wages earned ($700 x 10,000 = $7,000,000) per death.
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