A highly regarded IT specialist Ben Kemp explains that many businesses are misunderstanding what Google Analytics does. - Its is NOT a website traffic statistics package. If you want webstats you must use server log data stats.
Here is an extract from the Ben Kemp's website The SEO Guy:
Google Analytics is NOT designed to record website traffic statistics accurately. Google Analytics is far from accurate, especially when compared directly against server log files. G A is intended to track and analyse what people do when on the site. That’s why its called 'Google Analytics' and not 'Google Statistics'…
GA results are indicative rather than absolute, and are best used to identify trends, assess poor performing pages, monitor effectiveness of Adwords advertising campaigns and track visitor behaviour on the site.
GA should not be suggested or recommended as an accurate way to measure web site traffic – that’s NOT what its designed for.
A client asked me this question recently 'Why are you adverse to Google Analytics? Surely if one uses that consistently it is a constant so even if it is not 100% accurate the information it provides is relative.'
My answer was 'Trying to use Google Analytics to assess web site traffic is like using a screwdriver to undo a nut… And yes, you can keep doing it over and over again. However, the result is always going to be suboptimal!' Google Analytics and Vistor Activities:
GA is designed to monitor what people do when they are on your website; the pages they landed on, where they go internally, and where they exit from. It’s a behavioural tool… Its good at measuring conversion ratios – what percentage of people follow the traffic flow 'funnel' you’ve visualised and end up doing whatever it is you’d like them to do. Regardless of whether thats making a purchase, filling in a contact form or joining a mailing list, you’d like to know if things are getting worse or better…
You can edit a page and monitor the impact on conversions… you can alter your Unique Selling Proposition, or Call to Action, and measure the impact…
Another limitation of GA for large websites is the use of sampling in the generation of many of its reports.
To reduce the load on their servers and to provide users with a relatively quick response for their query, GA limits reports to 200,000 randomly sampled visits at the profile level for its calculations. While margins of error are indicated for the visits metric, margins of error are not provided for any other metrics in the GA reports. For small segments of data, the margin of error can be very large. Other Ways That Dilute Accuracy of Google Analytics results.
Many people also set their browser to clear cookies on exit
Code may not be correctly implemented Website Traffic Analysis
If you want to know the answers to the 'how many' type of questions then you should look in the server log files using AwStats (used by TetraMedia ed.) or Webalizer. These are installed on and accessible from, most hosting account…
Real traffic volumes are measured extremely accurately by the web server, and recorded in log files. To really see what’s happening, you need to look at the hosting account’s traffic analyser software. Usually either Webaliser, or AwStats (or both). Of the two, AwStats is best because it excludes visits from all known search engine spiders and indexing agents, giving a much more accurate picture. Webaliser figures are often 30% – 50% higher because of that distortion.
The server log files allow publishers, such as TetraMedia to provide exact monthly banner impressions from websites and newsletters, because its important to understand that often only 30-50% of the subscriber to a newsletter will open a particular edition. So you need to ask publishers exactly how their banner impressions are compiled. Website Statistics Summary:
You want to know more than either Google Analytics or server log files can tell you on their own:
BUT Do not fall in the trap of thinking Google Analytics are Google Statistics.
You need to use actual webserver log files with the website traffic statistics, to assess total visitors, where they came from, how long they stay etc.
To really understand whats happening, you need to use BOTH mechanisms… and you need to understand the strengths and weaknesses of each.
When looking at webstats provided by publishers, you need to see ad banner impression data, produced directly from the logs.
It is very important.