Damn lies and cat statistics

Heard the one about the cat in the stat?



I'm talking about the seemingly endless list of cat statistics wielded with enthusiasm by everyone from the staunchest cat advocate to the fiercest cat enemy. You know, how a single unspayed cat can produce enough cats to cover the earth twice over in a week?



For my SFGate.com column this week, I spoke to our own Gina Spadafori, Vox Felina blogger Peter J. Wolf, and Pulitzer Prize-winning science writer and science journalism professor Deborah Blum.

"I kept coming across some very dubious claims," (Wolf) told me. "And the more I'd dig into them, the worse it got. You'd start out thinking there was broad support for a particular claim, but you'd start drilling down a little bit and see all the references supporting that claim pointed to the same flawed study. So this 'broad support' became questionable."



[....]



"Take the estimates of how many birds are killed each year by cats," he said. "A 1993 article usually called 'the Wisconsin study' is constantly being cited, with an estimate that between 8 and 219 million birds were killed by free-roaming rural cats in that state."



But 15 years ago, study co-author Stanley Temple told the Sonoma County Independent, "The media has had a field day with this since we started. Those figures were from our proposal. They aren't actual data; that was just our projection to show how bad it might be."



Despite that apparently definitive disclaimer, Wolf discovered that the study and those numbers are still being cited in such publications as the New York Times (2007) and the Journal of Conservation Biology (2009). Even the U.S. Fish and Wildlife Service cites the study, he said.

There are a number of reasons why these kinds of numbers gain traction, some related to cats specifically -- people who hate cats, the sheer scope of the real threats to bird populations, like habitat destruction and pollution -- but the problem extends far beyond the cat issue.

Pulitzer-prize winning science writer Deborah Blum feels Wolf's pain, too. Blum, a journalism professor at the University of Wisconsin - Madison, said, "In science journalism, we spend a lot of time looking at this particular problem. Why do some numbers get this bizarre traction? Why do people believe it, when if they did a little digging they'd find it's not only wrong but in some cases even does harm?"

Why, indeed? Find out here.

Comments

[Gina Spadafori]

One of your absolute BEST.

[Christie Keith]

Wow, Gina, thank you! And thanks for your help!

[YesBiscuit!]

Always happy to see these things debunked. Maybe if it gets said enough, some people will actually check it out for themselves to get the facts.

[Pamela]

Excellent post! "Sticky numbers" and incomplete understandings of scientific studies circulate through the media contributing to sloppy thinking and bad decision making all the time.



Thanks for spreading the word on these oft-repeated bits of incomplete info.

[Valerie]

Fantastic article! Thanks for combating some really sloppy thinking.