Likewise, the WAIS system was not fully exploited either. Since both systems are evolving, the results from this study must be considered in the context of the current state of the art. In addition to these limits on how the systems were used, this study was limited by the small number of questions, the fact that relevance judgments were made only by the requestor rather than a panel of experts, and the often-noted problems of making relevance judgments in general. As stated earlier, the objective of this investigation was to compare the capabilities of Boolean and vector-based retrieval systems, emphasizing the strengths and appropriate uses of each. The preliminary results of this investigation and the experience gained in working with both systems on the same questions provide useful information toward this goal and point out questions needing further study.
BBSs offer powerful search capabilities for professional searchers.
The main strengths are related to high levels of control over how search is conducted. The system can yield high recall values if high recall strategies are used, and high precision if high precision strategies are used. Thus, BBSs provide a good range of features for constructing searches customized to specific user needs. Features such as proximity operators and file limits give the searcher greater control in constructing a search query and allow results to be interpreted directly. Additionally, there is a large base of experience in using this type of system and extensive research on various search techniques and strategies.