In Douglas Hofstadter's article "On number numbness" (published in Scientific American and also in his book Metamagical Themas) he mentions that he did an estimation exercise with one of his (university) classes, asking them to estimate the height of the Empire State Building. The smallest answer: 50 feet. The largest: one mile. (I don't think he asked them for confidence intervals or anything of the kind.)

(A height of 50 feet means about 6 inches per floor.)

One mile is a believable data point for somebody who knows it's really tall and has no clue how tall buildings generally are and has no skills in estimating or reasoning to be able to come up with a good estimate, but I think "50 feet" as an estimate is not a legitimate data point. It is much more likely that somebody was being a smart ass, or wanted to screw up the experiment and make Hofstadter look silly, or had never heard of the Empire State Building (assuming Hofstadter didn't imply that it's a really tall building) and was just guessing for a random building (which it would still be a bad estimate for, but much less so).

2PhilGoetz11yEverything's up-to-date in Kansas City! They've gone about as fur as they can go. They went and built a skyscraper seven stories high, About as high as a building oughta go! -- from Oklahoma with apologies to current residents of Kansas City

Calibration fail

by PhilGoetz 1 min read9th Aug 200936 comments


I was talking on Friday with two people who've been to Italy recently and saw the leaning tower of Pisa.  One of them was surprised at how short it was:  "about 30 feet tall", she said.  Then the other person, who'd also seen it, agreed that it was surprisingly short, and said it was "only about as tall as the Washington Monument".

"Wait," I said. "You just said it's 30 feet tall; and you just said it's as tall as the Washington monument, which has got to be at least 100 yards tall.  And you agreed with each other."

And they both shook their heads, and said, "No, the Washington Monument isn't anywhere near 100 yards tall."  We all live near Washington DC, and have seen the Washington Monument many times.

I said that the Washington Monument must be taller than that.  One of them said that it was just as tiring to walk to the top of the Leaning Tower as to walk to the top of the Washington Monument; which was odd, since the WM stairs have been closed since before he was born.

They finally agreed that both structures were about 30 yards tall.

The Leaning Tower is 183 feet tall, and the Washington Monument is 555 feet tall.