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Statistical Accuracy of Internet Weather Forecasts

markmcb writes "Brandon Hansen considers the statistical accuracy of popular on-line weather forecast sources and shows who's on target, and on who you probably shouldn't rely. Motivated by a trip to a water park that was spoiled with hail despite a 'clear sky' forecast, he does a nice job of depicting deviations, averages, and overall accuracy in a manner that stats junkies are sure to love."

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  1. Re:Can we believe the forecasts? by Daniel+Dvorkin · · Score: 5, Insightful

    What I find funny is that the entire practice of weather prediction is based on a logically fallacy. They take the data from previous years and say, ok, last time conditions looked like this x happened, so we predict x will happen again. Anybody who's taken an introductory logic class knows that you can't correlation does not equal causation.

    And anyone whose understanding of correlation goes beyond "an introductory logic class" knows that in fact, as long as you're very careful about what you're doing, you can in fact very often use observed correlations to make valid predictions.

    There's this whole field of study called "statistics," see. Not the "X% of people surveyed believe Y" type of thing you hear on the news, but an actual science, grounded in rigorous mathematical theory and growing more sophisticated all the time at producing useful knowledge from mountains of data. People get PhD's in it and stuff. Really. Maybe you ought to read about it some time. Maybe even take a class.

    Or perhaps you'd rather remain secure in your prejudices, repeating "correlation does not equal causation" like a mantra, snickering at people whose knowledge you choose not to understand.

    --
    The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.