In the swirl of current news and political tempests, we all need some basic fact-checking skills...
... and I'm curious about what you do to exercise the ability to do some basic checks on the things you read.
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A wave of assertions comes at you every day.
Which are correct? Which ones do you check? How do you check?
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For instance, I recently read an article that claimed that over 1 million acres of California had burned this year. True or not?
As you lead your life, hearing or reading the news, you'll get many such assertions: Politician X said outrageous statement Y. Or that some terrible / horrifying policy is have such-and-such an effect on the environment / group of people / city / state.
There's a lot of this going around these days. I know what I do, but I'm curious about what you do in your day-to-day practice. And this leads to our Challenge for the week:
1. About how often do you spend the time to fact-check something you learn about?
2. When you DO decide to look up something, what motivates you to do so?
3. What do you do to fact-check? (Do you have a preferred set of sites that you appeal to for the inside story? How much backtracking of data do you do?)
4. Finally, do you have a story about a fact that you checked recently? Can you tell us what you did and how you went about checking?
In my case, when I read about the "1 million acres of California had burned this year" I was suspicious. That seemed like a really large number.
A quick back of the envelope calculation (aka Fermi Estimation, as we discussed a while back) told me that 1M acres is roughly 1600 square miles (about 4600 square km). A space that size would be 40 miles on a side. The distance from San Francisco to Mountain View (the Googleplex) is about 40 miles, and going east from there takes you to the edge of the Central Valley.
I did a quick sketch in Google Maps to get a sense of the size of 1M acres (that is, 1600 square miles). Here's what I drew. (The calculation is done automatically by Google Maps.)
Now that I see it this way, the 1M acres number is fairly plausible.
LNU Lightning Complex: 375,209
SCU Lightning Complex: 396,624
Creek Fire: 152,833
CZU Lightning Complex: 86,509
W-5 Cold Springs: 74,819
375,209 + 396,624 + 152,833 + 86,509 + 74,819 = 1,085,994
And that's just the top 5 fires in the state, and none of them are contained. There are 58 fires listed on that page--so this implausible / outrageous number is in fact a low estimate. The reality is much higher and we're still a couple of months away from the end of fire season.
But you see my point: the number sounded too large to be true, but a quick estimate of what 1M acres looks like suggests that it's not an implausible number. Doing a quick search to get some data from a reliable source tells me that it's way low. The reality is, by the end of the year, going to be more like 2M acres of California consumed by wildfire.
In this case my fact-check strategy was to find a reliable source of data (the SF Chronicle Fire Map, which collects data directly from satellite data). In their methodology section (which they actually included in the article--hurrah!), the fire perimeters are based on infrared and thermal imaging from NASA's MODIS and VIIRS-I data products.
This isn't a complex fact-check, but it shows my key point.
But now I'm curious about your behavior. What do YOU do to fact-check things you see and hear?
Let us know by posting in the comments.
Search on!
