Value of a Statistical Life — A crude estimate of the value to society of saving a life. VSL estimates are sometimes based on estimates of average wages and earnings, to assess society's loss of a productive worker. Or VSL numbers can be based on trying to empirically observe how much people actually seem to be willing to pay to avoid risks, either as individuals or as a society. For example, a civil engineer might use a VSL number when making a CBA estimate to decide whether to install a guard rail on the side of a highway. Studies often use different VSL numbers for people in different countries, but I would argue that ethically we should consider all people to have similar VSL numbers, without regard to race, sex, or nationality.