"The fundamental principle of risk communication can be summarized in a number, [which] is the correlation between how much harm a risk does and how upset people get about it. If you look at a long list of risks, and you rank them in order of how upset people get [about them], then you rank them again in order of how much harm they do, then you correlate the two, you get a glorious 0.2....
That is, the risks that kill people and the risks that upset people are completely different. If you know that a risk kills people, you have no idea whether it upsets them or not. If you know it upsets them, you have no idea whether it kills them or not.
If you replace mortality with morbidity in the calculation -- you're not killing people, you're just making them sick -- our correlation remains 0.2. If you use ecosystem damage, the correlation is once again 0.2, and if, as this group likes to do, you correlate economic damage with public concern, the correlation is 0.2.
It doesn't seem to matter what your measure of harm is. Whatever your measure of harm, across a wide range of risks, the correlation between how much harm [a risk is] going to do and how upset people are going to get is this absurdly low 0.2 correlation."