Even if he’s right, dKos is still doing as much as us and MM put together. Is he right? I’ve heard other people complain, as Ruffini does, that a front-page link at dKos makes for a surprisingly small spike but that may be less suggestive of hits being overcounted than readers pouring into individual diaries instead of the front page. The crux of his argument is that SiteMeter only “remembers” 100 visitors at any one time, which means that if you click over to dKos and then wait for a few seconds while 100 new people stream in, the next click you make will count as a totally separate visit. So assuming that dKos receives 100 new visitors every 12 seconds, you could conceivably account for five visits yourself in the span of one minute if you space out your clicks appropriately. To wit:
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.
Ruffini’s talking about visits, specifically. According to SiteMeter, though, “visits” are defined as “a series of page views by one person with no more than 30 minutes in between page views.” In other words, if Ruffini’s right, you’re going to have overcounting on any site that attracts more than 100 visits in any 30-minute span.* Granted, most blogs get small enough traffic that that shouldn’t be a problem but SM’s been the industry standard for big blogs too since 2002. I find it hard to believe they wouldn’t have either corrected this glitch yet or at least noted it somewhere for the benefit of new customers. In fact, compare SM’s free basic service to the premium service: for $6.95 a month, SM will provide details for the last 4,000 visits, not the last 100. Which means, if Ruffini’s glitch theory is correct, that a premium account will result in a much lower (and more accurate) visit count than a free, basic account. That’s an odd feature to include in your pay service, especially when bloggers depend upon higher visit counts for ad rates.
He makes a good point, though, about how visits shrink to impossibly small durations according to SM’s metrics as sites get bigger. I’m not sure how to explain that other than the way he does. I’ll leave you with this — Dan Riehl’s side by side comparisons of dKos, Instapundit, National Review, and MM using the independent (and imperfect) metrics of Alexa. As you’ll see from his last graph, dKos’s “reach” — defined as the percentage of global Internet users who visit a site according to Alexa’s best guesstimates — is roughly three times that of MM and InstaGlenn. If Ruffini’s SM glitch theory is correct, MM’s “real” traffic numbers are on the order of 130,000 visits a day. That suggests, but of course doesn’t prove, that Kos’s traffic is quite a bit higher than the “real” number of 283,000 that Ruffini attributes to him. Here’s another graph of dKos and Instapundit head to head. Glenn’s “real” traffic would probably be 150,000 or so according to Ruffini’s theory. Kos is still way up:
Exit question: Am I right or did I miss something?
* Actually, this is incorrect. You’re going to have a risk of overcounting in these circumstances, but whether any overcounting actually occurs will depend on whether there are repeat visitors during that 30-minute period and how long they took between clicks.