In recent years, in the context of the vector space model, the view, held by many researchers, that documents, queries, terms, etc., are all elements of a common space has been challenged (Bollmann-Sdorra & Raghavan, 1993). In particular, it was noted that term independence has to be investigated in the context of user preferences and it was shown, through counterexamples, that term independence can hold in the document space, but not in the query space and vice versa. In this article, we continue the investigation of query and document spaces with respect to the property of term independence. We prove, under realistic assumptions, that requiring term independence to hold in the query space is inconsistent with the goal of achieving better performance by means of weighted retrieval. The result that term independence in the query space is undesirable is obtained without making any assumption about whether or not the property of term independence holds in the document space. The results of this article reinforce our position that the properties of document and query spaces must be investigated separately, since the document and query spaces do not necessarily have the same properties.

In this article, the relational structures of the numerical probability, belief, plausibility, and ambiguity functions are analyzed. A non-numerical measure is introduced for each numerical function. These non-numerical measures can be viewed as qualitative measures of ignorance, as they define the same relational structures as their numerical counterparts. The result of this analysis is important because it establishes the basis for adopting a particular non-numerical function to measure ignorance. © 1996 John Wiley & Sons, Inc.

Many authors, who adopt the vector space model, take the view that documents, terms, queries, etc., are all elements within the same (conceptual) space. This view seems to be a natural one, given that documents and queries have the same vector notation. We show, however, that the structure of the query space can be very different from that of the document space. To this end, concepts like preference, similarity, term independence, and linearity, both in the document space and in the query space, are discussed. Our conclusion is that a more realistic and complete view of IR is obtained if we do not consider documents and queries to be elements of the same space. This conclusion implies that certain restrictions usually applied in the design of an IR system are obviated. For example, the retrieval function need not be restricted to the ones that have the possibility to be interpreted as a similarity measure. © 1993 John Wiley & Sons, Inc.

There are important theoretical and practical reasons to study belief structures. Similar to qualitative probability, qualitative belief can be described in terms of a preference relation. The precise conditions that a preference relation must satisfy such that it can be faithfully represented by a belief function are specified. Two special classes of preference relations identified are weak and strict belief relations. It is shown that only strict belief relations are consistent (compatible) with belief functions. The axiomization of qualitative belief provides a foundation to develop a utility theory for decision making based on belief functions. The established relationship between qualitative probability and qualitative belief may also lead to a better understanding and useful applications of belief structures in approximate reasoning.>

article Free Access Share on Retrieval system evaluation using recall and precision: problems and answers Authors: V. V. Raghavan The Center for Advanced Computer Studies, University of Southwestern Louisiana,P.O. Box 44330, Lafayette, LA The Center for Advanced Computer Studies, University of Southwestern Louisiana,P.O. Box 44330, Lafayette, LAView Profile , P. Bollmann Technische Universitat Berlin, Fachbereich Informatik, FR 5-l1, Franklinstraβe 28/29, D-1000 Berlin 10 ,West Germany Technische Universitat Berlin, Fachbereich Informatik, FR 5-l1, Franklinstraβe 28/29, D-1000 Berlin 10 ,West GermanyView Profile , G. S. Jung The Center for Advanced Computer Studies, University of Southwestern Louisiana,P.O. Box 44330, Lafayette, LA The Center for Advanced Computer Studies, University of Southwestern Louisiana,P.O. Box 44330, Lafayette, LAView Profile Authors Info & Claims ACM SIGIR ForumVolume 23Issue SIJune 1989 pp 59–68https://doi.org/10.1145/75335.75342Published:01 May 1989Publication History 11citation1,293DownloadsMetricsTotal Citations11Total Downloads1,293Last 12 Months25Last 6 weeks11 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my Alerts New Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteeReaderPDF

Recall and precision are often used to evaluate the effectiveness of information retrieval systems. They are easy to define if there is a single query and if the retrieval result generated for the query is a linear ordering. However, when the retrieval results are weakly ordered, in the sense that several documents have an identical retrieval status value with respect to a query, some probabilistic notion of precision has to be introduced. Relevance probability, expected precision, and so forth, are some alternatives mentioned in the literature for this purpose. Furthermore, when many queries are to be evaluated and the retrieval results averaged over these queries, some method of interpolation of precision values at certain preselected recall levels is needed. The currently popular approaches for handling both a weak ordering and interpolation are found to be inconsistent, and the results obtained are not easy to interpret. Moreover, in cases where some alternatives are available, no comparative analysis that would facilitate the selection of a particular strategy has been provided. In this paper, we systematically investigate the various problems and issues associated with the use of recall and precision as measures of retrieval system performance. Our motivation is to provide a comparative analysis of methods available for defining precision in a probabilistic sense and to promote a better understanding of the various issues involved in retrieval performance evaluation.

In this paper the expected search length, which is a measure of retrieval system performance, is investigated from the viewpoint of axiomatic utility theory. Necessary and sufficient criteria for the expected search length to be an ordinal scale and sufficient criteria that it is a ratio scale are given.

Based on the concept of user preference, we investigate the linear structure in information retrieval. We also discuss a practical procedure to determine the linear decision function and present an analysis of term weighting. Our experimental results seem to demonstrate that our model provides a useful framework for the design of an adaptive system.

Missing, non-applicable and imprecise values arise frequently in Office Information Systems. There is a need to treat them in a consistent and useful manner. This paper proposes a method and gives the precise semantics of the retrieval operations in a system where imprecision is allowed. It also suggests a way to handle the uncertainty introduced by imprecise data values.

Besides the operators 'and', 'or' and 'not' the GRIPS retrieval language contains thesaurus — operators to extend the query and truncation — and context-operators for freetext and Boolean searching.

The normalized recall is one of the most popular evaluation measures for information retrieval systems. In this paper an overview of its development is given. It is then shown that the normalized recall is closely related to other measures such as the CRE-measure and the expected search length. Some implications are analysed.

article Restricted evaluation in information retrieval Share on Authors: P. Bollmann Technische Universität Berlin Technische Universität BerlinView Profile , V. S. Cherniavsky Technische Universität Braunschweig Technische Universität BraunschweigView Profile Authors Info & Claims ACM SIGIR ForumVolume 16Issue 1Summer 1981 pp 15–21https://doi.org/10.1145/1013228.511757Online:31 May 1981Publication History 5citation252DownloadsMetricsTotal Citations5Total Downloads252Last 12 Months1Last 6 weeks0 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteGet Access