How Many Visitors?

I used to be very heartbroken about how few people read my blog--I was getting a real inferiority complex that I average about 1000 to 1100 visitors a day, while Instapundit averages 200,000 visitors a day. Is Instapundit 200x more interesting? Or are there really 200x more libertarians than conservatives?

Patrick Ruffini has a very useful discussion of how the traffic statistics for Dailykos (the hard left blog that increasingly runs the Democratic Party--or at least gives the impression that it does) are grossly inflated:

So I started to do some digging around his SiteMeter stats and those of other big bloggers.
My source was right. The SiteMeter numbers are indeed fishy. But the reason is far from nefarious: a design flaw in how SiteMeter counts visits that systemically overcounts unique visitors on extremely high traffic blogs like Daily Kos… by a lot.
First of all, I looked at the Detail view showing the last 100 visitors. Overwhelmingly it showed visitors hitting the site only once, with a visit time of zero (you need to hit a second page for it to register any time spent). Contrasted with my traffic, with an average visit length of three minutes, this seemed highly improbable.
Then it hit me: SiteMeter only accounts for the last 100 visitors individually. On a site like Daily Kos, the 100th most recent visitor could have been 15 seconds ago. If you are the 101st most recent visitor and you click on a new page, you are counted as a new unique visitor in SiteMeter’s all important count. On a normal site, this wouldn’t matter, since it’s highly unlikely you’ll stick around long enough to have 100 others show up after you. On a site with hundreds of thousands of page views a day, it’s extremely likely you will.

So it might well be that the bloggers for whom I suffer visitor envy aren't getting 200x as many unique visitors as I am--perhaps the difference is only 100x or 75x. My guess is that the average visit length (how long a visitor is believed to have spent on that page) gives some idea of how inflated the unique visitor count might be. I notice that Instapundit's stats show an average visit length of five seconds before they click onto something else. For my page, it is one minute, eight seconds--suggesting that people are spending more time reading what I have to say, or that the "last 100" quirk Ruffini mentions above is creating misleading average visit length figures as well.