Objective response detection in the frequency domain.

R A Dobie; M J Wilson

doi:10.1016/0168-5597(93)90040-v

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PubMed · 7694837

Objective response detection in the frequency domain.

R A Dobie·M J Wilson

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Abstract

Several different and related measures have been proposed for objective response detection in the frequency domain. We compared magnitude-squared coherence (MSC) to phase coherence (PC) using simulations with specified signal-to-noise ratios (SNRs) and varying numbers of subaverages; the performance measure was area under a receiver operating characteristic (ROC) curve. MSC was superior to PC; test time required for equivalent performance is about 3 times greater for PC than for MSC. MSC performance for a given final SNR increased with the number of subaverages, but reached a plateau at 16 subaverages. Simulations of noise non-stationarity (high-amplitude noise in some subaverages compared to the others) led to decreased performance advantage for MSC over PC. However, weighted averaging restored this advantage. MSC is shown to be a simple algebraic transform of Victor and Mast's (1991) "circular T2" statistic and of two earlier statistics; all have identical statistical power.

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Computer Simulation Electroencephalography Evoked Potentials Humans Models, Neurological ROC Curve Signal Processing, Computer-Assisted Journal Article Research Support, U.S. Gov't, P.H.S.

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R A Dobie, M J Wilson. Objective response detection in the frequency domain.. https://doi.org/10.1016/0168-5597(93)90040-v

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