Brad Efron wrote to me and posed an interesting statistical question:
“Last Wednesday Diane Sawyer interviewed an Oklahoma woman who twice
had had her home destroyed by a force-4 tornado. “A one in a
hundred-trillion chance!” said Diane. ABC showed a nice map with the
current storm’s track of destruction shaded in, about 18 miles long
and 1 mile wide. Then the track of the 1999 storm was superimposed,
about the same dimensions, the two intersecting in a roughly 1 square
mile lozenge. Diane added that the woman “lives right in the center of
Question: what odds should have Diane quoted? (and for that matter,
what is the right event to consider?)
Anyone have a good answer?
By the way, I should add that Diane Sawyer has a history of
broadcasting stories filled with numerical illiteracy. She did a long
series opposing the use of lean finely textured beef (LFTB), also
known as “pink slime.” In fact, LFTB is perfectly healthy, its use
requires slaughtering many fewer cows each year and makes meat cheaper
for poor people. The series was denounced by many scientists and even
environmentalists. ABC is being sued for over one billion dollars.
She also did a long series on “Buy America” encouraging people to
shun cheap goods from abroad. This is like telling people who live in
Cleveland to shun buying any products and services not produced in
Cleveland (including not watching ABC news which is produced in New
York, or reading statistics papers not written in Cleveland.) This
high-school level mistake in economics is another example of Ms.
Sawyer’s numerical illiteracy.
But I digress.
Let’s return to Brad’s question:
What is a good way to compute the odds that someone has their house
destroyed by a tornado twice?
I open it up for discussion.