“How do we know which numbers to trust and which health studies are
sound? Healthland faces this dilemma every day, so we spoke with Charles
Seife, the rare journalist with an undergraduate degree in mathematics,
from Princeton no less. In his book Proofiness: The Dark Arts of
Mathematical Deception, Seife explores the common ways math can be used
to mislead people.
What is “proofiness”?
It’s the art of using math to tell untruths, the art of using bogus numbers or numbers that are semi-right to mislead.
One example I like is when Quaker Oats had a huge ad campaign to try to
convince people that eating oatmeal could lower cholesterol
dramatically. It put a graph on the back [of the package] that showed a
dramatic decline in cholesterol levels. And there was a drop, according
to a study. But if you look carefully, the Y-axis was manipulated so
that a really very tiny drop looked huge, when in fact, there was only a
few points [decline] out of 200.
And what is the phenomenon you call “randumbness”?
We humans have a hard time recognizing that things can actually have no
[discernible] cause. They are random. The roll of the dice isn’t
influenced by external factors [like wearing your lucky shoes]. That’s
how Las Vegas makes all its money. People think that if they’re winning,
they should keep doing [what they're doing]; if they’re losing they’re
due to win soon. The universe doesn’t care whether you win or lose —
things are just random.
So, it’s the fallacy that comes when we think something is [causally
connected to something else], when in fact there’s no cause behind it. I
like to link it to what I call cause-uistry — what happens when, say,
there is a cancer cluster or you spot a group of people who have more
than the expected number of a certain type of cancer. It may be that
there’s a toxin or something causing it. But by the sheer fact that you
are looking at the entire country, of course there are going to be some
places where there is a more-than-average incidence of cancer. Just
through random chance, in some places there will be an increase in
cancer, and in some places it will be lower than expected.
So cause-uistry is a glib name for the fallacy that correlation
equals causation. Just because two things seem to be related doesn’t
mean that one affects the other. [Still] our brains lead us to connect
things even if they are not connected. One fun example: when I was doing
reporting on something else, a member of Congress tried to pitch me on
building more power plants. He said that if you increase power
production, then infant mortality drops. It’s true. It’s also true that
when Internet use goes up, infant mortality drops. And car driving. Of
course, those are all symptomatic of a high-tech society that has good
health care.”
Read more at Time Healthland
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