Top three mistakes in analysis of web logs.
Visitors or Hits
It is a common mistake when looking at data from a web site to base many calculations off of hits. This is mostly caused by a misinterpretation of the word in forums, eMail, newsletters and web pages. Hits are a numeric count of the number of items that appear on a webpage. Every image, text block, table, etc. counts as a hit when a page loads. Visitor is a numeric count of how many IP addresses (i.e., people) visit the web site. Unless all of your web pages have exactly the same number of items it is very difficult to use hits as a basis for making decisions regarding traffic. Even if every page has the same number of items and you divide the Hits total by that number of items to obtain how many actual pages were viewed, and most analysis already provide the page view count. Page views are important so you can determine how many pages your visitors look at before making the purchasing decision to leaving the site ratio and determining how much time people spend looking at a web page. This is a totally different set of analysis than how you use Visitor information and brings the discussion full circle to why it is vital to understand the difference between counting hits and counting visitors. The number of visitors to your web site is used to verify the effectiveness of advertising, promotions, and growth strategies. Often visitor total is divided by the total number of sales as a measure of web site performance, while hits are a vital measure for bandwidth. Bandwidth is far less critical today than it was a decade ago when most web site tables were created and is seldom used as a performance measure now.
Identify Unique Visitors
There's been a lot of conversation in the past year about first- and third-party cookies' impact on tracking. Third-party cookie rejection and deletion are only increasing. Enough on the cookie front; why does it really matter? To have accurate data, you must configure your tracking tool to be able to accurately differentiate between different visitors when they come to your site. Depending on your site, there are a number of ways to do this, everything from keying a unique login ID when people log in (for private or secured site areas) to a first-party cookie to other, less common ways to differentiate visitors.
If you don't have an effective way to differentiate between site visitors within a given session (visit) and on returning sessions (unique visitors), understanding site traffic will be very difficult. Make sure you've looked at this and, based on your tool and situation, have found an accurate way to differentiate between visitors.
Ensure All Pages Are Tracked
Another common issue is not all site pages get included in the analysis. You end up with holes in the story and the paths people take through the site. This can also throw off entry and exit page reports and other metrics that may help you understand movement through the site, as well as key drivers. This frequently happens in both log-file and page-tagging solutions. Log files can be left out of the analysis, and pages can be missing tags. Page tags can be missed through the initial tagging process or as new pages are rolled out.
Not being able to differentiate between pages is another thing that can occur in both page-tagging and log-file based solutions. Here's a simple example: when a form is submitted, it returns the same page (and URL) or redirects people to the home page. In this case, it's difficult to determine how many people submitted the form. Another issue is when a series of different pages show up as the same page. This is most commonly caused by pages controlled by parameters when the data collection tool isn't set up to differentiate between pages based on parameters. It can also be caused within some page tagging solutions when the same page name (within the tool) is placed on multiple pages. In this case, many different pages will show up under the same page name in the tracking tool, aggregating all the information for those pages so they appear as a single page. Obviously, in certain situations this can cause major problems and confusion.
Conclusion
As you make critical decisions about your web site business such as ad spending, page design, pricing, competitive advantage, etcetera all based on the web site data, you absolutely must have valid data from the start. It only takes one misinformation or a faulty data collection software to cost you valuable dollars, time, and loss to the competition. The Online Statistician reports 10 to 30 percent of the data received from clients are invalid. In working with its customers the first step is verifying accurate data in order to verify actual performance results from all marketing efforts. Using data is the only method you can use to make sure your business is improving, and it is critical to use the right information and the right collection programs to ensure you are making the right management decisions.
