What’s the most important metric when it comes to determining the health of your site? It’s not really a fair question since no one metric tells the entire story, but for a long time page views have been considered one of the most important metrics. Page views don’t tell the whole story of course. Does someone look at a lot of your pages because they like your content or because they can’t find what they’re looking for? And with the rise of Ajax applications how meaningful is to to measure when your entire application is on one page? Recently there’s been a movement toward time spent as a measure of engagement with your site, though that has it’s share of problems too. So how is one to measure visitor engagement with your site.
Yesterday I came across a post at Fresh Egg with a new formula called the engagement factor, which I think has a lot of merit in measuring how people interact with your site. The formula is pretty simple.
Engagement Factor = (Avg time on site (seconds) x Pages per visit) / Bounce Rate
What I like about the engagement factor is it makes sense. It measures page*seconds/visit which does sound like engagement. While time spent and pages per visit each aren’t perfect in measuring engagement, chances are as each value increases a visitor is interacting more with your site.
Again that’s not 100% true. Visitors might visit a lot of pages because they can’t find what they want. They may leave your page open in a tab in the background while they surf other sites and close your page before ever reading it. But combined they probably help to limit the other’s inaccuracies. The person who leaves the page open in the background and closes it isn’t visiting a lot of pages. The person who can’t find what they’re looking for doesn’t spend a lot of time on the site.
Not perfect, but better.
Considering bounce rate it makes sense that people who never click beyond the entry page aren’t engaging with your site. As bounce rate goes up engagement goes down. That’s exactly how the formula calls it too. Looking at the example from the Fresh Egg post it seems like they’re using 50 as the divisor in the equation when the bounce rate is 50%. It would be better to call it .50, but since the end result is simply a ratio and the number are more readable using 50 it’s not a big deal.
My post on developing a 2 column css layout has usually done well bringing search traffic. Two thing I’ve always noticed is the page has a high bounce rate, but visitors also average a fair amount of time on the page, more than enough to read and digest it. Now I’m probably not doing a good enough job getting people to click through from that page to another on the site, but the high average times on the page lead me to believe people are finding it useful. I would think they are still engaged with the page even if the page doesn’t lead them to visit the rest of the site.
Given the engagement factor is calling for pages/visit this isn’t something you can use to measure interaction with a single page, but rather your entire site. And it is something that will need to be looked at in relation not as an absolute. Saying your engagement factor is 25 is meaningless except in comparison to last month’s 22.
The engagement factor might not be perfect, but from what I’ve seen so far it’s as good as any metric for measuring how visitors interact with your site. I think it’s a good start toward measuring visitor engagement that could possibly be developed into something more.
What do you think? Does the engagement factor seem like a good way to measure user interaction with your site? What might be missing? What flaws might it have? Would you use it to gage the health of your site?