Det relativa värdet av ämnesingångar i databaser
Variationer mellan discipliner
This thesis deals with tactics for information seeking in electronic databases. An important aspect is knowledge of the relative value of different subject access points. The method used here is literature studies. Nineteen empirical studies are described and analysed with the purpose to compare the relative value of different subject access points. The studies examined compare the relative value of subject access points in relation to each other or in relation to different scientific disciplines. The studies cover the three broad knowledge domains of humanities, social science and science. The methods used in the studies have serious limitations and many subjective variables related to the use of the precision and recall measures makes it difficult to draw any clear conclusions concerning tactics when searching subject access points. Studies indicate that document representations in the humanities and social sciences are constructed with science as a model with serious implications for retrieval and the thesis criticizes information retrieval theory for ignoring domain specific theories. Studies that measure the overlap between subject access points are found to be valuable in determining to what extent the different subject access points complement each other. Another method that is valuable is failure analysis of searches in databases which gives information concerning why searches fail. Both these methods show that different subject access points retrieve unique relevant documents and the conclusions of this thesis therefore lends support to the need for a theory of the relative value of subject access points. In the future there is therefore reason to focus on the way different subject access points complement each other instead of focusing on which is most effective.