Population Statistic: Read. React. Repeat.
Tuesday, April 21, 2021

My already-shaky faith in humanity takes yet another direct hit from news that barely half the population actually understands how the percentages used in weather forecast probabilities work:

If, for example, a forecast calls for a 20 percent chance of rain, many people think it means that it will rain over 20 percent of the area covered by the forecast. Others think it will rain for 20 percent of the time, said Susan Joslyn, a cognitive psychologist at the University of Washington who conducted the study.

The reality: “When a forecast says there is a 20 percent chance of rain tomorrow it actually means it will rain on 20 percent of the days with exactly the same atmospheric conditions,” Joslyn explained.

Put another way, on that day there’s an 80 percent chance there will be no rain anywhere in the forecast area.

My mind’s boggling… I can almost see how that percentage figure could be assigned to time and/or space, only because I experienced wacky Florida weather that resulted in torrential downpours only a couple of miles away from sun-shiny skies. I guess if you grow up with that climactic activity, you could mistake the formalized “probability of precipitation”.

But come on. How hard is it to suss out the real meaning? They’ve been using these measures for forty years now, on the friendly TV screen no less. You’d have to be willfully ignorant to not be able to understand the weather report by now.

I suppose this will bring a call for some sort of dumbed-down method of forecasting. Ultimately meteorology will reduce itself to sticking your head out the window and guessing (not that it’s too far from that now anyway).

by Costa Tsiokos, Tue 04/21/2009 12:12:26 PM
Category: Society, Weather
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Okay, Monday. Fess up.

I know it’s you here today. I know the calendar says Tuesday, but really, c’mon. This day is you all over: The rotten weather, the herky-jerky subways, the long lines, the exceedingly stupid people (and the long lines made longer by the ever-exceedingly stupid people).

You tried to sneak in for a repeat back-to-back performance this week. But the jig is up. You’ve somehow usurped this second weekday, but now I’ve outed you. That won’t stop you from your carrying out your malevolent streak, but just so we’re clear.

by Costa Tsiokos, Tue 04/21/2009 10:27:07 AM
Category: New Yorkin', Society, Weather
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