best of 2008 (2) : big theorems
Charles Siegel of Rigorous Trivialities ran a great series on big theorems.
The series started january 10th 2008 with a post on Bezout’s theorem, followed by posts on Chow’s lemma, Serre duality, Riemann-Roch, Bertini, Nakayama’s lemma, Groebner bases, Hurwitz to end just before christmas with a post on Kontsevich’s formula.
Also at other blogs, 2008 was the year of series of long posts containing substantial pure mathematics.
Out of many, just two examples : Chris Schommer-Pries ran a three part series on TQFTs via planar algebras starting here, at the secret blogging seminar.
And, Peter Woit of Not Even Wrong has an ungoing series of posts called Notes on BRST, starting here. At the moment he is at episode nine.
It suffices to have a quick look at the length of any of these posts, to see that a great deal of work was put into these series (and numerous similar ones, elsewhere). Is this amount of time well spend? Or, should we focus on shorter, easier digestible math-posts?
What got me thinking was this merciless comment Charles got after a great series of posts leading up to Kontsevich’s formula :
“Perhaps you should make a New Years commitment to not be so obscurantist, like John Armstrong, and instead promote the public understanding of math!”
Well, if this doesn’t put you off blogging for a while, what will?
So, are we really writing the wrong sort of posts? Do math-blog readers only want short, flashy, easy reading posts these days? Or, is anyone out there taking notice of the hard work it takes to write such a technical post, let alone a series of them?
At first I was rather pessimistic about the probable answer to all these questions, but, fortunately we have Google Analytics to quantify things a bit.
Clearly I can only rely on the statistics for my own site, so I’ll treat the case of a recent post here : Mumford’s treasure map which tried to explain the notion of a generic point and how one might depict an affine scheme.
Here’s some of the Google Analytics data :

The yellow function gives the number of pageviews for that post, the value ranges between 0 and 600 (the number to the right of the picture). In total this post was viewed 2470 times, up till now.
The blue function tells the average time a visitor spend reading that post, the numbers range between 0 and 8 minutes (the times to the left of the picture). On average the time-on-page was 2.24 minutes, so in all people spend well over 92 hours reading this one post! This seems like a good return for the time it took me to write it…
Some other things can be learned from this data. Whereas the number of page-views has two peaks early on (one the day it was posted, the second one when Peter Woit linked to it) and is now steadily decreasing, the time-on-page for the later visitors is substantially longer than the early readers.
Some of this may be explained (see comment below) by returning visits. Here is a more detailed picture (orange = new visits, green=returning visits, blue=’total’ whatever this means).

All in all good news : there is indeed a market for longer technical math-posts and people (eventually) take time to read the post in detail.
Another possible explanation for the longer page-views later on is the following sort of behavior: I check for new blog posts quite frequently (say, once per day). But it’s not every day that I feel like reading a long post. In particular, while I was probably part of one of your big yellow peaks, I think the day I actually read the post lies in the “blue-dominated zone”.
Does anyone else do this?
(Although I haven’t played with Google Analytics, it’s probably not too hard to look for this sort of behavior.)
Alexander Ellis
3 Jan 09 at 9:55 pm edit_comment_link(__('Edit', 'sandbox'), ' ', ''); ?>
Alexander, true enough. Ive checked returning/new visits and altered the too drastic conclusion of the post. Thx!
lieven
3 Jan 09 at 10:42 pm edit_comment_link(__('Edit', 'sandbox'), ' ', ''); ?>
Alexander, I also do this. And as for that comment I got…it’s best just to ignore Noted Scholar…he’s trying to make a point, but can’t articulate it well to the rest of us.
Charles Siegel
4 Jan 09 at 1:56 am edit_comment_link(__('Edit', 'sandbox'), ' ', ''); ?>
Ack, and I meant to put this into my comment, but hit “post” by accident: what’s the relevance of the picture on top? That’s actually from a program I was in as an undergrad, and I know the guy (there’s a picture of me giving my talk from that on the webpage that originally appeared on).
Charles Siegel
4 Jan 09 at 1:58 am edit_comment_link(__('Edit', 'sandbox'), ' ', ''); ?>
Hi, I’m a student studying math at the University of Tokyo.
I’m one of those who are taking the time to read your recent post (Mumford’s treasure map), and hopefully I’m planning to introduce this post to my friends studying in Japan.
I appreciate you taking the time to write this great post, and I’m looking forward for your future “longer technical math-posts”.
Masaom
5 Jan 09 at 3:04 am edit_comment_link(__('Edit', 'sandbox'), ' ', ''); ?>
Masaom, thanks! It’s always good to know one doesn’t blog in vain (although my little stats-experiment already gave me alrerady a better feel on this).
Charles : a picture a post goes with the current theme i’m using. if the guy isn’t you, blame it on google images. whoever it is, isn’t in too bad company if you have a look at the front-page. there are blackboard-pictures of ‘the guy’, connes, lenstra, manin and kontsevich… if you would believe in stats, the guy is in for a fields medal (or should have gotten it long ago).
oh, and masaom, there will be longer math-posts soon, only one more 2008-post is on my mind….
lieven
5 Jan 09 at 6:32 pm edit_comment_link(__('Edit', 'sandbox'), ' ', ''); ?>