EXPERIMENTAL RETRIEVAL SYSTEMS STUDIES. REPORT NO. 3

Advancements in state of the art high density Head/Disk retrieval systems has increased the demand for sophisticated failure analysis methods. From 1968 to 1974 the emphasis was on the number of tracks per inch. (TPI) ranging from 100 to 400 as summarized in Table 1. This emphasis shifted with the increase in densities to include the number of bits per inch (BPI). A bit is formed by magnetizing the Fe203 particles of the media in one direction and allowing magnetic heads to recognize specific data patterns. From 1977 to 1986 the tracks per inch increased from 470 to 1400 corresponding to an increase from 6300 to 10,800 bits per inch respectively. Due to the reduction in the bit and track sizes, build and operating environments of systems have become critical factors in media reliability.Using the Ferrofluid pattern developing technique, the scanning electron microscope can be a valuable diagnostic tool in the examination of failure sites on disks.

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Explanatory Power for Medical Expert Systems: Studies in the Representation of Causal Relationships for Clinical Consultations

Methods of Information in Medicine ◽

10.1055/s-0038-1635400 ◽

1982 ◽

Vol 21 (03) ◽

pp. 127-136 ◽

Cited By ~ 25

Author(s):

J. W. Wallis ◽

E. H. Shortliffe

Keyword(s):

Explanatory Power ◽

Prototype System ◽

Inference Rules ◽

Medical Expert ◽

Comprehensive Knowledge ◽

Different Types ◽

Medical Expert Systems ◽

Explanation System ◽

Systems Studies

This paper reports on experiments designed to identify and implement mechanisms for enhancing the explanation capabilities of reasoning programs for medical consultation. The goals of an explanation system are discussed, as is the additional knowledge needed to meet these goals in a medical domain. We have focussed on the generation of explanations that are appropriate for different types of system users. This task requires a knowledge of what is complex and what is important; it is further strengthened by a classification of the associations or causal mechanisms inherent in the inference rules. A causal representation can also be used to aid in refining a comprehensive knowledge base so that the reasoning and explanations are more adequate. We describe a prototype system which reasons from causal inference rules and generates explanations that are appropriate for the user.

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Relevance Predictability in Information Retrieval Systems

Methods of Information in Medicine ◽

10.1055/s-0038-1636254 ◽

1967 ◽

Vol 06 (02) ◽

pp. 45-51 ◽

Cited By ~ 6

Author(s):

A. Kent ◽

J. Belzer ◽

M. Kuhfeerst ◽

E. D. Dym ◽

D. L. Shirey ◽

...

Keyword(s):

Information Retrieval ◽

Experimental Conditions ◽

Treatment Groups ◽

Retrieval Systems ◽

Significant Difference ◽

Information Retrieval Systems ◽

High Predictability ◽

Intermediate Response ◽

Quantitative Indicators ◽

Level Of Processing

An experiment is described which attempts to derive quantitative indicators regarding the potential relevance predictability of the intermediate stimuli used to represent documents in information retrieval systems. In effect, since the decision to peruse an entire document is often predicated upon the examination of one »level of processing« of the document (e.g., the citation and/or abstract), it became interesting to analyze the properties of what constitutes »relevance«. However, prior to such an analysis, an even more elementary step had to be made, namely, to determine what portions of a document should be examined.An evaluation of the ability of intermediate response products (IRPs), functioning as cues to the information content of full documents, to predict the relevance determination that would be subsequently made on these documents by motivated users of information retrieval systems, was made under controlled experimental conditions. The hypothesis that there might be other intermediate response products (selected extracts from the document, i.e., first paragraph, last paragraph, and the combination of first and last paragraph), that would be as representative of the full document as the traditional IRPs (citation and abstract) was tested systematically. The results showed that:1. there is no significant difference among the several IRP treatment groups on the number of cue evaluations of relevancy which match the subsequent user relevancy decision on the document;2. first and last paragraph combinations have consistently predicted relevancy to a higher degree than the other IRPs;3. abstracts were undistinguished as predictors; and4. the apparent high predictability rating for citations was not substantive.Some of these results are quite different than would be expected from previous work with unmotivated subjects.

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