Can web-based statistic services be trusted?

Abstract: A large number of statistic services exist today, which shows that there is a great interest in knowing more about the visitors on a web site. But how reliable is the result the services are giving? The hypothesis examined in the thesis is: Web-based statistic services do not show an accurate result The purpose of the thesis is to find out how accurate the web-based statistic services are regarding unique visitors and number of pages viewed. Our hope is that this thesis will bring more knowledge about the different statistic services that exists today and the problems surrounding them. We will also draw attention to the importance of knowing how your statistic software works to be able to interpret the results correctly. To investigate this, we chose to do practical tests on a selection of web-based statistic services. The services registered the traffic from the same web site during a test period. During the same period a control program registered the same things and stored the result in a database. In addition to the test, we have done an interview with a person working with web statistics. The investigation showed that there are big differences between the results from the web-based statistic services in the test and that none of them showed an accurate result, neither for the total number of page views nor unique visitors. This led us to the conclusion that web-based statistic services do not show an accurate result, which verifies our hypothesis. Also the interview confirmed that there is a problem with measuring web statistics.