Analytics

3 Algorithm Changes & 3 GA Changes in 30 Days

From Panda to 12-Pack Site Links and GA changes in session tracking and image search, can you trust any GA numbers?

Google Change History July-August 2011

Well, yes. Just because you read about a change, doesn’t mean you’re affected. It is always best to check your own numbers when you consider any of these type of changes. And as Brett covered in his post last week, GA can give you deceptive results. The nice thing is, you can often find these anomalies within the GA data itself with a little digging.

Your Actual Image Impact May be Minimal

At SEER, we started to see some increases in July around the time of Panda 2.3 & the image referral change. We didn’t want to dismiss these increases as image referrals without checking our own numbers first. After reviewing about a dozen clients who experienced visit increases, I noticed that the image referral impact for most of our clients was very minor! Despite the dramatic look of the referral drop graphs, many clients had a very small amount of traffic in this area. Consider this:

Referrals from imgres moved to Search in Google Analytics

Yes, an 80% drop is good confirmation of that dramatic drop graph, but wait a minute, that’s only 47 visits that potentially shifted to Search. This particular site had about 48,500 search visits those weeks. That is a 0.10% impact. Most of our clients had impacts like this or even less.

Looking at Trends to Measure Real Impact

Of course, we did have some clients with a larger impact within the images that we didn’t want to dismiss. To look at these, I stacked the Organic Google Search Visit numbers with the Image Visit Numbers in Excel. Notice that the net effect is still up.

Although Image Referral Visits moved to Search, the net effect is still up.

Using Unique Visitors to Assess Panda & 12-Pack Impact

For the session tracking issue, SEOMoz already covered looking at Pageviews and Unique Visitors to see through the GA session tracking issue.

Applying a similar concept, to look at the impact of the 12-pack I created a very simple custom report that looks at Unique Visitors first by Source, then drills to Keyword. (If you don’t want to make it yourself you can use mine.)

With just one week of data, we see the site brand is getting a slight boost, and brands they carry are taking a slight hit. Our overall Google impact is about 1% so far, but to really draw any conclusions we’ll need a few more weeks living with the 12-pack.

Using Unique Visitors we can asses the impact of the 12-Pack branded links on visits outside of the session change issue.

Check Your Numbers

As I said at the beginning, this post started because we were checking our own numbers against the issues brought up by other bloggers. Every client we looked at had a different impact for each of these 6 changes in the last 30 days. Once you’ve checked your numbers, leave a comment below and let us know what you’re seeing.