Have Hat, Will Travel

[beamjockey]

On Friday, I lost my hat. Fortunately, the loss was temporary.

There were extremely high winds most of Friday-- weather reports said 20 to 30 miles per hour. I was camping in Michigan and having a splendid time. I was wearing the hat I acquired from a souvenir dealer on the Piazza San Marco in 1989.

Comments

[del_c]

Why did you need Wolfram Alpha?

[tceisele]

But . . but . . . Wolfram Alpha is just *there*, practically *begging* people to use it. "Use me! Use me!" it whimpers planitively, crying out for our love. How could he *not* use it?

[beamjockey]

This is correct, pretty much. I didn't feel like deriving the relevant formulae myself.

I also didn't completely trust Wolfram Alpha (or my understanding of how to enter queries into it correctly), so I checked with another site that offered to compute distances, which gave nearly the same answer.

[beamjockey]

Months go by between opportunities to use Wolfram Alpha.

[tandw]

Good thing you found it, because (as we all know) any plan where you lose your hat is a bad plan.

[johnridley]

If you have two readings with an uncertainty of 2 meters each, isn't your net distance +/- 4 meters? I dunno, I'm no statistician, just wondering.

[tb_doc_smith]

If the readings are statistically independent, the uncertainty should be 2*sqrt(2) meters, or about 2.8 meters.

Not a statistician either, but they pay me to give lectures on detailed uncertainty analysis during the school year.

[beamjockey]

Not a statistician either, but they pay me to give lectures on detailed uncertainty analysis during the school year.

Obviously I could benefit from attending one.

Hours before posting this entry, I thought of computing the error, but forgot in the heat of the moment of posting.

[mmcirvin]

I suppose being really precise about the error would involve knowing the axes of the error ellipses for the two measurements (I think that with GPS it's often quite different from a circle). But adding them in quadrature like that is probably close enough.

[seawasp]

I hate to say this, but looking at that picture of you I keep hearing "Sit right back and you'll hear a tale, a tale of a fateful trip..."

[polyfrog]

That sounds like a similar distance to the ones I occasionally experience (roughly one Chicago city block). The hats are not exactly the same, but probably quite similar, aerodynamically speaking.

Of course, the wind speed and direction are a big factor as well. In the city, where my hat is most likely to be (because that is where my head is most likely to be), the wind is channeled and often concentrated by the surrounding buildings.