Thinking and Deciding

512 RISK
Although Option 2 leads to a total reduction of 5 cases, and Options 1 and 3 lead
to a total of 6 cases, 42% of the subjects (who included judges and legislative aides)
ranked Option 2 as better than one of the others.
In sum, the zero-risk bias is found in questionnaires as well as in real life. It may
have a normative justification. When risk is completely removed, people may worry
less, and the elimination of worry has utility. Note, though, that the worry itself
depends on a framing effect. Risk is never reduced to zero. (We all die eventually.)
When we think that risk is reduced to zero, it is because we have isolated some
particular risk, such as the risk of a certain kind of cancer from a certain hazardouswaste
site. The risk of cancer is still not reduced to zero, nor is the risk of cancer from
hazardous waste in general. Possibly, if people understood that what matters is the
total risk, they would worry more about the bigger risks that they can do something
about.
Individual versus statistical
There is a distinction between an individual life and a statistical life. Let
a 6-year-old girl with brown hair need thousands of dollars for an operation
that will prolong her life until Christmas, and the post office will be
swamped with nickels and dimes to save her. But let it be reported that
without a sales tax the hospital facilities of Massachusetts will deteriorate
and cause a barely perceptible increase in preventable deaths — not
many will drop a tear or reach for their checkbooks. (Schelling, 1968)
The quote is from an article on the value of life published in 1968. In 1987,
eighteen-month old Jessica McClure spent fifty-eight hours trapped in a well. Her
family received $700,000 in contributions, mostly in the months after her rescue.
Charities that advertise for money to help poor children often feature pictures of
individual children. Some even try to associate the donor with an individual child in
some far-off land. Why do people seem to place a higher value on individual lives as
opposed to statistical lives?
A study by Jenni and Loewenstein (1997) relates this effect to the proportionality
effect just described (after failing to find evidence for other explanations, such as
vividness). The idea is that saving a single life is seen as correcting 100% of the
problem, while a small reduction in the death rate is seen as a small proportion of
the problem of “premature” death. Provision of identifying information, such as a
picture, increases willingness to help in the case of a single individual, but not in the
case of helping a group (Kogut and Ritov, 2005).
Natural versus artificial
People are more concerned about artificial risks than about natural ones. Synthetic
chemicals added to food are often banned because they cause cancer in tests on
animals. Yet, if natural foods are broken up into their constituent chemicals, these too