Results of Hold On… How Many Copies? Contest

As predicted, I did not meet my self-imposed deadline of posting the winner of the Hold On… How Many Copies? contest on Saturday. But I think you’ll agree I have a good excuse. When I woke at my in-laws on Saturday morning, my wife and kids surprised me with the pronouncement that we’d be spending the day at the Museum of Mathematics in New York City. (A post about that coming soon. It was awesome!) But after a full day of mathematical thinking and a late dinner, I didn’t have the energy to post results last night.

So, sue me.

But without further adieu, I can now announce the winner. Not before some data analysis, though.

The ten responses were:

{21, 137, 301, 333, 392, 429, 453, 595, 1637, 3142}

With a range of 3,121 and an average of 744, there was quite a spread to the data.

I certainly love the optimism of the respondent who predicted that 3,142 copies were sold! But with Q1 = 390 and Q3 = 559, the responses of 1,637 and 3,142 would both be considered outliers. Indeed, the actual number was lower than either of those guesses, but you won’t hear me complain about selling 634 copies of Math Jokes 4 Mathy Folks from Dec 15 to Dec 21!

The winner guessed 595 copies. Well done! He or she will be contacted via email or can contact me directly at patrick@mathjokes4mathyfolks.com.

For what it’s worth, I would not have won my own contest. Knowing that sales vs. rank is generally exponential but also knowing that sales decline during the third week of December, I used a purely linear regression to generate a guess of 473 copies. This would have resulted in a third-place finish. Oh, well. I take solace knowing that a third-place finish is far superior to where I would have placed if I had sponsored a marathon instead.

So, thanks to everyone who bought a copy of the book last week. Wow! Who would’ve thought sales would still be that brisk five years after publication! For that matter, thanks to everyone who’s ever bought a book. This has been an incredible ride!

Thanks, also, to those of you who entered the contest. Sorry if you didn’t win, but I hope you had fun playing.

Happy holidays!