Asking the Right Questions, A Guide to Critical Thinking, 8th Ed

160 Chapter 11
do you need before you can judge the impact of the statistics^ Let's look at two example
to illustrate the usefulness of this question.
1. Large businesses are destroying the small town feel of our "downtown"
area. Just last year, the number of large businesses in the city has increased
by 75 percent.
2. Despite common fears, skydiving is much safer than other activities, such
as driving a car. In one particular month, in Los Angeles, 176 people
died in car accidents while 3 died in skydiving accidents.
In the first example, 75 percent seems quite impressive. But something is
missing: The absolute numbers on which this percentage is based. Wouldn't
we be less alarmed if we knew that this increase was from four businesses to
seven, rather than from 12 to 21? In our second example, we have the numbers,
but we don't have the percentages. Wouldn't we need to know what
these numbers mean in terms of percentages of people involved in both
activities? After all, there are fewer total skydivers than there are people
traveling in cars.
When you encounter impressive-sounding numbers or percentages,
be wary. You may need to get other information to decide just how impressive
the numbers are. When only absolute numbers are presented, ask
whether percentages might help you make a better judgment; when only
percentages are presented, ask whether absolute numbers would enrich
their meaning.
Another important kind of potential missing information is relevant comparisons.
It is often useful to ask the question, "As compared to ... ?"
Each of the following statements illustrates statistics that can benefit
from asking for comparisons:
• Medusa hair spray, now 50 percent better.
• SUVs are dangerous and should not be allowed on the road. In 2004,
SUVs were responsible for 4,666 deaths. Certainly something needs to
be done.
• Movie budgets are outrageous nowadays. Just look at Star Wars: Revenge of
the Sith, the budget for that movie alone is $115,000,000!
With reference to the first statement, don't you need to ask, "50 percent
better than what?" Other ineffective hair sprays? Previous Medusa brand