@Glen_b I seem to recall you posting your frustration about misuse of the terms "parametric" and "non-parametric". I've had somebody explain to me today that if the =SKEW function in Excel returns a value of zero, then it tells you that the data is parametric. But if =SKEW returns "zero point something or minus zero point something" (their words), then the data is non-parametric.

I did try to track down where this claim might have arisen, whether there might be some "rogue textbook" as you were hypothesising, but apparently this is straight from their university's statistical handbook that they got given as a student.

(They studied biological sciences, in case you're keeping a tally chart of parametric abuse by field.)

@Silverfish "if the =SKEW function in Excel returns a value of zero, then it tells you that the data is parametric. But if =SKEW returns "zero point something or minus zero point something" (their words), then the data is non-parametric." --- Oh boy, so much fail in two brief sentences. It needs to be enshrined somewhere. There ought to be a museum. Thanks for that.

I just facepalmed so hard I have finger marks on my forehead.