title: Performances of human listeners and an automatic aural classifier in discriminating between sonar target echoes and clutter.
abstract: Human listening tests were conducted to investigate if participants could distinguish between samples of target echoes and clutter obtained from a broadband active sonar experiment. For each echo, the listeners assigned a rating based on how confident they were that it was a target echo or clutter. The measure of performance was the area under the binormal receiver-operating-characteristic (ROC) curve, A(z). The mean performance was A(z)=0.95 ± 0.04 when signals were presented with their full available acoustic bandwidth of approximately 0-2 kHz. It was A(z)=0.77 ± 0.08 when the bandwidth was reduced to 0.5-2 kHz. The error bounds are stated as 95% confidence intervals. These results show that the listeners could definitely hear differences, but their performance was significantly degraded when the low-frequency signal information was removed. The performance of an automatic aural classifier was compared against this human-performance baseline. Results of statistical tests showed that it outperformed 2 of 13 listeners and 5 of 9 human listeners in the full-bandwidth and reduced-bandwidth tests, respectively, and performed similarly to the other listeners. Given its performance, the automatic aural classifier may prove beneficial to Navy sonar systems.
authors: Defence R&D Canada - Atlantic, P.O. Box 1012, Dartmouth, Nova Scotia B2Y 3Z7, Canada. Nancy.Allen@drdc-rddc.gc.ca
authors: Nancy
authors: N
authors: Allen
authors: Paul C
authors: PC
authors: Hines
authors: Victor W
authors: VW
authors: Young
mesh_terms: D000161:Acoustic Stimulation; D001299:Audiometry; D001306:Auditory Pathways / Q000502:physiology*; D001307:Auditory Perception; D001331:Automation; D016009:Chi-Square Distribution; D006801:Humans; D015233:Models, Statistical; D009622:Noise; D012372:ROC Curve; D017603:Signal Detection, Psychological; D012815:Signal Processing, Computer-Assisted; D013647:Task Performance and Analysis; D014465:Ultrasonics; D014867:Water
chemical_list: D014867:Water