The value of statistical life (VSL) is of major importance to cost-benefit assessment of road infrastructure investments, road maintenance planning, and to traffic control decisions, such as limitation of speed. It seems however to be of a ghostly nature that escapes precise empirical measurement. A major problem blurring the image catched by various preference-revelation instruments is the size bias, i.e. that measures of willingness-to-pay (WTP) for road safety are unreasonably insensitive to the size of the risk reduction. When the WTP for a larger risk reduction is almost the same as for a smaller risk reduction, the VSL will be inversely proportional to the size of the risk reduction. Therefore the WTP per unit of risk reduction, which is the VSL, can be more or arbitrarily set to any number within a wide range, i.e., it will be high for a small risk reduction and low for a large reduction. While similar problems have been encountered for other benefits as well, they seem to be more difficult to overcome for safety improvements that result in small size probability reductions ts of a contingent valuation study in Sweden that takes scale bias as a fact. Instead of targeting a central-value estimate of VSL, we attempt to find a lowerbound estimate of what we call the value of a serious statistical accident, VSSA. This is based on a conservative assessment of the WTP for a risk reduction eliminating fatal and serious-injury accidents . We search for values from respondents reporting high confidence in their answers, and estimate values within both private and public good contexts. Dividing this value with the whole baseline risk of fatal and serious-injury accidents gives the lower-bound VSSA estimate. Based on the results corresponding to a public safety program, we conclude that an upward revision of the combined unit value of fatalities and serious injuries used in Swedish infrastructure planning is warranted. Our estimates do indeed imply that the willingness to pay of fully confident respondents is proportional to the size of the risk reduction, but this result is not statistically significant. The result for the private good is close to the VSL suggested by previous studies. However, unlike these assessments this is a lower-bound estimate and the scope of VSSA is wider, as it applies also to serious injuries. As infrastructure planning is made in the public-good context, we recommend the public-good value estimate for use in CBA models. Within this context we also estimate the effect of a provision condition intended to reduce free-riding strategic response from 'conditional cooperators'. For road accidents in Sweden in general, and for road accidents in the urban areas of the city in which this study was made, there are approximately seven times as many reported seriously injured victims as the number of persons killed. The "Vision Zero" public-safety program for the city that was valued in this study was supposed to prevent two fatalities and fourteen serious injuries per year. The annual social benefit of such a program is according to the presently used CBA-models 76 million SEK. With the lower-bound public-program VSSA estimate of our study, the value of the corresponding "bundle" is 119 million SEK. Thus, although this study does not give support for an increase of the currently used VSL value, it does imply that the benefits accruing from safety measures that target accidents with mortal or serious-injury outcomes on average are larger than the currently assessed values. For the covering abstract please see ITRD E135207.
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