Has anyone made a switch from a server log approach to a page tagging approach for web measurement?    

For many reasons our server log data had never been processed to meet ABCe requirements (we don't sell advertising space for a start!) and undertandably the page tagging approach is showing a significant difference in unique visitors and visits. 

I'm having trouble getting buy in on the new figures so any 'me too' stories (anonymous or otherwise) would be gratefully received,

Jeanette

Hi Dan,

Thanks for your quick reply.  We're seeing a significant drop in unique visitors, visits and page views across the board.  It seems to big a drop to be apportioned to search engine's only but wondered if anyone had a similar experience.

Jeanette

Hi Jeanette

I've never met anyone whose traffic/stats have gone up as a result of moving from log file analysis to page tags. And that's always been because the log file analysis stats have been overstating traffic - unfortunately it is almost always the lower number which is more accurate!

As John says the 2 most common reason for overstatement of traffic for log file analysis are:

1. Non-human traffic is being counted. And there's increasing amounts of non-human traffic out there! As much as 20% of site visits for some sites. With page tags, which tend to use JavaScript, the non-human traffic is not counted. 

2. The same user is being counted as multiple users. This is where a 'user' is uniquely identified by IP address. If that IP address keeps changing (as it does for most consumers using ISPs) then that same person will be counted as a different user each time.

The above is somewhat of a simplification and can, to a large degree, be avoided even with log file analysis. For example, you can try and filter out non-human activity from your stats; you can also use a cookie instead of an IP address to identify unique users. 

For an excellent overview of the pros and cons of the various approaches you should read Dr Brian Clifton's "Web Traffic Data Sources" paper - something we contributed to.

Regards

Ashley Friedlein
CEO, E-consultancy.com

Decreases can also occur with page tags if they are the kind which need to be put into every page / template and you omit to put them into all the relevant places, of course...!

Ashley