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A study was undertaken to classify mechanically a document collection using the free-language words in the titles and abstracts of a corpus of 261 physics research papers. Using a clustering algorithm, results were obtained which closely duplicated the clusters obtained by previous experiments with citations. A brief comparison is made with a traditional manual classification system. It is shown that the mechanical procedure Is capable of achieving simultaneous average relevance and recall figures above 80%. [ABSTRACT FROM AUTHOR]

This paper defines a hash coding model for non-unique search keys and derives the expected number of accesses needed to retrieve all desired records from a computer storage device. The assumption that the records are stored on the basis of a non-unique key is often realized in information retrieval environments. The model assumes that the hashing algorithm and, should a collision occur, the skipping algorithm, both distribute the records randomly in memory. The results of this analysis are compared with those from a simulation in which the randomness criterion is not strictly met. [ABSTRACT FROM AUTHOR]

The problem of whether to bind, microcopy or discard back issues of journals in a university library branch system is considered and an algorithm is developed to solve the journal disposition problem. A cost-effectiveness approach is pursued, employing an analytical model. This model uses a set of weighted factors to quantify the value of a specific journal to the library. Such factors as relevance, usage, availability elsewhere and capital investment are specified. Budget constraints, which involve the relevant costs of binding and microcopying, are considered, as are upper and lower threshold values on the worth of a journal to guarantee the retention of exceptionally good journals and the disposal of very poor ones. An example based on data from a real university special library situation is presented as an illustration of the model. Thus, this paper extends the work of others in modeling of the library collection development decision process. [ABSTRACT FROM AUTHOR]

The deductions which may be made from inspection of a citation map of the literature are briefly described, and a search algorithm is given for the construction of such maps. Following the construction and assessment of a network describing the development of amorphous semi- conductors, it is concluded that citation diagrams are a valuable aid for socio-scientific studies. [ABSTRACT FROM AUTHOR]

This paper describes the development and application of an algorithm which generates non-linear representations of English text. The algorithm uses the results of a syntactic analysis system and a set of rules which prescribe linkages to generate a graph of a sentence. The shape of these graphs corresponds to the syntax of the sentence; the labels correspond to the vocabulary of the sentence and the edge types correspond to case grammar roles. The sentence graphs can then be interconnected at common nodes and analyzed according to common edges. Preliminary experimentation has yielded promising results. It appears that the algorithm produces a representation of English text which could be quite useful in automatic language processing. [ABSTRACT FROM AUTHOR]

Frequently it is useful to abbreviate or otherwise transform keys used for the retrieval of information. These transformations include the compression of long keys into a fixed field length by operations on characters or groups of characters, hash or random transformations in order to obtain a direct address, or phonetic coding to order to group together keys that are in some way similar. The various transformations have differing effects on file retrieval schemes. Given a transformation algorithm and data to be transformed, it is possible to characterize certain qualities of the algorithm that re late to retrieval problems. This paper is concerned with some measures of effectiveness of such transformation algorithms. [ABSTRACT FROM AUTHOR]

This paper presents mathematical evaluation measures to characterize the effect of known erroneous performance by stemming routines, and generalizes these procedures to other types of nonstatistical clustering algorithms. When clusters, or groups of intrinsically related elements, are split into smaller groups (by under-matching the elements), there is a loss in recall in information retrieval; larger groups (caused by over- matching) induce a loss in precision or relevance. The magnitude of error is taken to be a function of frequencies of cluster elements. When these ore words in a subject-term index generated by a stemming algorithm, retrieval capability is also affected by the strength of the algorithm, the size and content of the stemmed index, and the number of words in a query. The present Project Intrex stemming algorithm has estimated stemming-error losses of 4% in recall and 1% in relevance on one-word queries; the former could be reduced to almost zero by straightforward corrections of known errors in the algorithm. An expanded probabilistic model is introduced to handle a more general case in which any element need not belong unambiguously to a single cluster. Error evaluation in document classification and thesauri also is discussed in broad terms. [ABSTRACT FROM AUTHOR]

A clustering algorithm which is tree-like in structure, and is based on user queries, is presented. It is compared to Bonner's Method, Rocchio's Method, Dattola's Method and the Single Link Method in three different aspects, namely system effectiveness, system efficiency and the time required for clustering. Experimental results using the Cranfield 424 collection indicate that the proposed method is superior to the other methods. [ABSTRACT FROM AUTHOR]

An experiment using a computer to assign content designators to unedited machine readable bibliographic data to create MARC records is described. Input typing conventions are briefly discussed. A computer program (Assembler Language for DOS) is being developed which analyzes unedited data according to predefined algorithms and builds MARC records. A manual simulation using 150 catalog records was done to test the computer algorithms. The results of the test in terms of accuracy and throughput compared favorably with the current MARC input system in use at the Library of Congress. [ABSTRACT FROM AUTHOR]

The article discusses how the computer is used to extend the teacher's facilities and capabilities. The computer provides three important advantages in helping to understand concepts. It provides the opportunity for discovery, exploration, and extension, opportunities that are often lacking with ordinary instructional methods. Computerized instruction not only requires more precise communication, but also offers a chance to be creative. This creativity might be expressed by the construction of an algorithm to solve a given problem, or of one to explore a new topic.

The article informs that researcher Frederick Kilgour's algorithm for forming search keys for automated library catalogs was tested in a file of about 2000 books in science and technology and in a file of about 2000 books in art and literature. Both 3-3 and 2-2 author-title search keys were tested. It was found that both types of search keys yielded a significantly greater number of false-drops in the file of science and technology than in the file of art and literature. Frederick Kilgour and his associates have developed an algorithm for forming search keys for automated library catalogs. These search keys consist of the first few letters of the author's last name concatenated with the first few letters of the first non-article word of the title.