Fail: Area Circles on Wall Street

Posted to Mistaken Data  |  Nathan Yau

I know next to nothing about the economy, stocks, and investments, but I do know a little bit about charts and graphs. The above area circles were prepared by someone at JP Morgan. I don’t know, you might have heard of ’em. The circles are based on data from Bloomberg and meant to show the change in market value from 2007 to 2009. The problem here is that the creator sized circles by diameter instead of area, so the difference looks ginormous. I mean, the value change is significant but not that big.

Here’s the revised version from a Big Picture reader, Rene Corda:

Now look at the original version again. Big difference, right?

Circles are 2-dimensional shapes. You can’t use them and expect people to compare two circles by diameter, a 1-D metric. Sorry, JP Morgan person. You fail.

Check out the Big Picture for some more graphs of the same data.

[via Cringely | Thanks, Barry]

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