FURTHER EXPERIMENTS ON THE RANGE OF VISUAL SEARCH

Abstract

The report describes six experiments on visual search. Two essential terms in the report are critical number and basal time, defined by the following operations. Median latency of search is plotted as a function of the number of elements in the matrix, for each subject and experimental condition. At low numbers of elements the latency is nearly constant; this is the basal time. Then there occurs a transition to longer latencies. The critical number of the number of elements at which the transition occurs. The aim of the first experiment was to discover whether the critical number varies with the density of the stimulus matrix. Over the entire range of densities employed, it does. Nevertheless, the area corresponding to the critical number is apparently constant over a range of low densities. (This is the area of fast search.) over a range of high densities, this area decreases considerably. Basal time does not vary with density. The second experiment aimed to check the first one, and to provide evidence on the shape of the area of fast search. The analysis was in terms of the location of the critical elements in the matrix. The constancy of area at low densities was confirmed, although the check was very insensitive. Basal time is constant. The shape of the area appears to be as previously described: ovaloid, with the longer axis horizontal.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1965
Accession Number
AD0622414

Entities

People

  • Horace H. Corbin
  • John Volkmann

Organizations

  • Mount Holyoke College

Tags

Communities of Interest

  • Human Systems

DTIC Thesaurus Topics

  • Accuracy
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  • Materials
  • Measurement
  • Photographs
  • Photography
  • Psychology
  • Reliability
  • Standards
  • Visual Acuity

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Materials Science and Engineering.
  • Vision Science/Vision Psychology/Cognitive Neuroscience.