Predicting the Difficulty of Locating Targets from Judgments of Image Characteristics

Item

Title
Predicting the Difficulty of Locating Targets from Judgments of Image Characteristics
Date
1964
Index Abstract
Not Available
Photo Quality
Complete
Report Number
AMRL TDR 64-19
Creator
Rhodes, Fen
Corporate Author
Aerospace Medical Research Laboratories
Laboratory
Behavioral Sciences Laboratory
Extent
59
PB Number
PB126711
Identifier
AD0601375
Access Rights
OTS
Distribution Classification
1
Contract
Laboratory Research - No Contract
DoD Project
None Given
DoD Task
None Given
DTIC Record Exists
No
Distribution Change Authority Correspondence
None
Distribution Conflict
No
Cover Price
1.25
Abstract
Judgments of 12 characteristics of 200 aerial reconnaissance photographs, each containing a designated target, and physical measures of target size and location were related to (1) search time required to locate targets and (2) judged overall target difficulty. Twenty photointerpreters and 20 college students served as subjects. Photographs were divided into two equal groups to permit cross validation of results. A factor analysis of the data, including the two criterion measures, resulted in the extraction of eight orthogonal factors. These were identified as (1) target size, (2) picture sharpness and contrast, (3) picture detail, (4) logical restrictions on possible target location, (5) target shape and pattern, (6) target location, (7) target isolation, and (8) rater bias. Linear multiple-regression analysis yielded correlation coefficients ranging from .75 to .87 for predicting the logarithm of search time and .87 to .90 for predicting judged target difficulty from the 12 psychophysical judgments and the 2 physical measures. Cross validation of obtained prediction equations resulted in average correlations of .67 and .79 for search time and judged difficulty respectively. Raters were able to make highly reliable and seemingly valid judgments about complex perceptual characteristics of aerial photographs. There was no difference in reliability of validity between ratings made by photointerpreters and those made by untrained students.
Report Availability
Full text available
Date Issued
1964-03
Provenance
RAF Centre of Aviation Medicine
Type
report
Format
1 online resource
Media
AMRLTDR64-019.pdf