UKOLN AHDS Performance Indicators For Your Project Web Site


It is desirable to measure usage of your project Web site as this can give an indication of its effectiveness. Measuring how the Web site is being used can also help in identifying the usability of the Web site. Monitoring errors when users access your Web site can also help in identifying problem areas which need to be fixed.

However, as described in this document, usage statistics can be misleading. Care must be taken in interpreting statistics. As well as usage statistics there are a number of other types of performance indicators which can be measured.

It is also important that consistent approaches are taken in measuring performance indicators in order to ensure that valid comparisons can be made with other Web sites.

Web Statistics

Web statistics are produced by the Web server software. The raw data will normally be produced by default - no additional configuration will be needed to produce the server's default set of usage data.

The server log file records information on requests (normally referred to as a "hit") for a resource on the web server. Information included in the server log file includes the name of the resource, the IP address (or domain name) of the user making the request, the name of the browser (more correctly, referred to as the "user agent") issuing the request, the size of the resource, date and time information and whether the request was successful or not (and an error code if it was not). In addition many servers will be configured to store additional information, such as the "referer" (sic) field, the URL of the page the user was viewing before clicking on a link to get to the resource.


A wide range of Web statistical analysis packages are available to analyse Web server log files [1]. A widely used package in the UK HE sector is WebTrends [2].

An alternative approach to using Web statistical analysis packages is to make use of externally-hosted statistical analysis services [3]. This approach may be worth considering for projects which have limited access to server log files and to Web statistical analysis software.

Configuration Issues

In order to ensure that Web usage figures are consistent it is necessary to ensure that Web servers are configured in a consistent manner, that Web statistical analysis packages process the data consistently and that the project Web site is clearly defined.

You should ensure that (a) the Web server is configured so that appropriate information is recorded and (b) that changes to relevant server options or data processing are documented.


You should be aware that the Web usage data does not necessarily give a true indication of usage due to several factors:

Despite these reservations collecting and analysing usage data can provide valuable information.

Other Types Of Indicators

Web usage statistics are not the only type of performance indicator which can be used. You may also wish to consider:

With all of the indicators periodic reporting will allow trends to be detected.


It may be useful to determine a policy on collection and analysis of performance indicators for your Web site prior to its launch.


  1. Web server log files, UKOLN,
  2. WebTrends,
  3. Externally-hosted statistical analysis services, Exploit Interactive, Issue 5, April 2000,