Accession Number : ADA335270

Title :   Measures of the Discriminability of Symbol Shapes

Corporate Author : DEFENCE AND CIVIL INST OF ENVIRONMENTALMEDICINE DOWNSVIEW (ONTARIO)

Personal Author(s) : McFadden, Sharon ; Bauer, Ben ; McManus, Kelly

PDF Url : ADA335270

Report Date : DEC 1997

Pagination or Media Count : 41

Abstract : Participants rated the similarity of 90 pairs of symbols based upon ten geometric shapes. The discriminability of these shapes was then examined in a visual search task where participants enumerated the number of occurrences of a particular target shape found in a display of distractors. The results were submitted to correlation analysis and multidimensional scaling (MDS) analysis to examine the relationship between the similarity ratings and the visual search task. Based on the correlation analysis, subjective assessment can predict when two symbols will be highly discriminable. However in some cases, symbols rated as similar proved highly discriminable. The results of the multidimensional scaling analysis suggested that, in the similarity rating task, participants differentiated the symbols primarily on their overall geometric shape. However in the visual search task, participants appeared to use other dimensions such as vertical height and symmetry in discriminating the symbols. These findings in conjunction with the results of other researchers suggest that context and task both may influence the features used in discriminating symbols. Suggestions are made for additional research that would evaluate the relevance of these two factors more thoroughly.

Descriptors :   *COMPUTER GRAPHICS, *VISUAL PERCEPTION, *SYMBOLS, TARGET RECOGNITION, SHAPE, CANADA, TARGET DISCRIMINATION, CORRELATION, COLOR DISPLAYS, MAN COMPUTER INTERFACE.

Subject Categories : Computer Programming and Software
      Human Factors Engineering & Man Machine System

Distribution Statement : APPROVED FOR PUBLIC RELEASE