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Mark Atwood
An interesting lesson in knowing the limits of your metrics
I just looked at the WSDOT traffic status map.

And I got this image.

All the roads are green, all the traffic load indictors are good. I've never seen it that good. You would think that that means that right now the roads are moving clear and fast.

Wrong. RIght now the Seattle area is getting the worst winter storm in decades, and the traffic load sensors are all green, because there is no traffic, because nobody wants to drive in it.

Know what your metrics actually measure...
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awfief From: awfief Date: December 22nd, 2008 02:43 am (UTC) (Link)
Right. There is no traffic. That doesn't mean "clear and fast", that means "there isn't a heavy volume of cars on the road".

I watched the Seattle/Jets game and there were plenty of people there, so at some point there were plenty of people on the road :)
mauser From: mauser Date: December 22nd, 2008 11:04 pm (UTC) (Link)
On the other hand, the sensors north of SR2 are radar based speed detectors, instead of induction loop traffic counters.
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