You're looking at Less Wrong's discussion board. This includes all posts, including those that haven't been promoted to the front page yet. For more information, see About Less Wrong.

Kindly comments on Where Fermi Fails: What is hard to estimate? - Less Wrong Discussion

6 Post author: tgb 05 June 2012 03:15AM

You are viewing a comment permalink. View the original post to see all comments and the full post content.

Comments (46)

You are viewing a single comment's thread. Show more comments above.

Comment author: Kindly 05 June 2012 03:19:00PM *  4 points [-]

Mathematica says the exact value of y that maximizes the distance between arctan(1.1y) and arctan(0.9y) is 1/sqrt(0.99) which is approximately 1.00504 (its negative also works). Feynman should still choose 1, because this isn't a calculation to do in your head, and 1 is a good guess.

His chances of winning, however, are about 3.1%: the range of x-values that work is roughly 0.1, and the period of tangent is pi.

Comment author: faul_sname 05 June 2012 03:39:43PM 1 point [-]

Excellent solution. Looking back on my tinkering with excel, I made an error in how I determined whether or not Feynman would have been right.

Unsurprisingly, that method would have still given the wrong answer (a 3% chance still isn't very good), but it's an example of using your knowledge of the general behavior of a function to make an educated guess.