Research Abstracts

Educational technology research and development -     

Threshold values and Boolean retrieval systems

Several papers have appeared that have analyzed recent developments in the problem of processing, in a document retrieval system, queries expressed as Boolean expressions. The purpose of this paper is to continue that analysis. We shall show that the concept of threshold values resolves the problems inherent with relevance weights. Moreover, we shall explore possible evaluation mechanisms for retrieval of documents, based on fuzzy-set-theoretic considerations.     

Avoiding versus seeking: the relationship of information seeking to avoidance, blunting, coping, dissonance, and related concepts.

QUESTION: How have theorists and empirical researchers treated the human tendency to avoid discomforting information? DATA SOURCES: A historical review (1890-2004) of theory literature in communication and information studies, coupled with searches of recent studies on uptake of genetic testing and on coping strategies of cancer patients, was performed. STUDY SELECTION: The authors' review of the recent literature included searches of the MEDLINE, PsychInfo, and CINAHL databases between 1992 and summer of 2004 and selective, manual searches of earlier literature. Search strategies included the following subject headings and key words: MeSH headings: Genetic Screening/psychology, Decision Making, Neoplasms/diagnosis/genetics/psychology; CINAHL headings: Genetic Screening, Genetic Counseling, Anxiety, Decision Making, Decision Making/Patient; additional key words: avoidance, worry, monitoring, blunting, cancer. The "Related Articles" function in MEDLINE was used to perform additional "citation pearl" searching. MAIN RESULTS: The assumption that individuals actively seek information underlies much of psychological theory and communication practice, as well as most models of the information-seeking process. However, much research has also noted that sometimes people avoid information, if paying attention to it will cause mental discomfort or dissonance. Cancer information in general and genetic screening for cancer in particular are discussed as examples to illustrate this pattern. CONCLUSION: That some patients avoid knowledge of imminent disease makes avoidance behavior an important area for social and psychological research, particularly with regard to genetic testing.