Commune Media | Measurably Effective Digital Marketing™

Are your visitors absolutely unique?

Posted on Monday, November 23rd, 2009 at 12:45 PM by Jebadiah Roberts  |  Comments (0)

It’s bad enough that some analytics tools make it difficult to tell between visits and visitors. (For the record, a visit occurs when someone visits and browses your site, and a visitor is the person who does the browsing—there’s a big difference.) But even worse is the fact that some tools make it extremely difficult to accurately measure how many unique visitors—the number of individual people who perused your content—your site attracted during a given period.

In Web Analytics 2.0 (required reading for anyone who cares about doing well on the web) analytics guru Avinash Kaushik discusses the difficulty of separating the people (visitors) from the events (visits) with some tools, and a brief summary is in order.

Visits are typically simple to gauge. Most tools refer to them as such, or they call them “sessions,” which is still descriptive enough to get the job done. Some tools, however, confusingly refer to visits as “visitors,” making it difficult to distinguish between these basic metrics.

But things get a little more shaky when it comes to measuring unique visitors. While telling visits apart is easy, tools like Google Analytics have to distinguish between the people who visit a site by setting a unique cookie on each person’s browser. So if they visit again, the tool, which will now recognize them, will tally a new visit but not a new unique visitor.

Why some tools inflate visitor counts

Because some browsers don’t accept cookies or reject third-party cookies (an unavoidable fact that web analysts simply have to deal with), developing an accurate picture of your unique visitors is fraught from the start. And some tools further complicate this inaccuracy by breaking up the metric into “daily unique visitors,” “weekly unique visitors” and “monthly unique visitors.”

If you’re shopping around for an analytics tool or you’re using one that offers these additional metrics, you should probably understand just how useless these metrics are. Why? Because daily unique visitors will register as unique for every consecutive day they visit. The same goes for weeks, so if you’re analyzing your site’s performance over the course of a month (which you likely do unless your site is massive), your unique daily visitors and unique weekly visitors metrics will throw numbers at you that are completely out of proportion. In many cases you could easily end up with more visitors than visits.

The only visitor metric that matters

The answer to this visitor inflation is, of course, the “Absolute Unique Visitors” metric. If you’re used to using sophisticated, user-friendly tools like Google Analytics, XiTi or Nedstat, you might take this metric for granted. (You might even mistake it for jargon.) But know this: Not all tools are equal, and not every tool offers this complicated and (mostly) accurate metric. Your “Absolute Unique Visitors” report is the result of extremely complex and time-consuming calculation. It’s an extra mile that lazier tools with their “additional” metrics have simply avoided—much to the user’s detriment.

The lesson here? First, you should always question the importance of a particular measurement. Differentiating between daily, weekly and monthly visitors might seem like due diligence, but it’s really just laziness that can easily skew your data if you aren’t careful.

And when choosing an analytics tool, you should always place an emphasis on user-friendly naming conventions. Ask your vendor what they call a visit. If they say “visitor,” you might want to keep looking.

Most importantly, make sure you pick a tool that measures absolute unique visitors. Measuring unique visitors will never be a completely accurate process, but monitoring your absolute unique visitors is the closest you’ll come to correctly tracking this important metric.

Tags: absolute unique visitors, visitors, web analytics