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Log File
Net Station Waveform Tools Technical Manual S-MAN-200-WFTR-001 • December 21, 2006
4: Artifact Detection
After applying the Threshold Artifact Detection Settings to your data, you can view
the artifact-detection results in the text-based log file.
The log file contains failure records listing the channel number, segment number (if
applicable), settings to the parameters in the threshold specification, and offset into
the segment (if applicable) in which the failure occurred.
Perform Inferences
In the Perform Inferences section, you can specify what conclusions to make from the
bad-channel, eye-blink, and eye-movement information produced by the Threshold
Artifact Detection Settings section. For segmented data, you can specify the
criteria that will mark a segment bad because of bad channels, eye blinks, and eye
movements. For continuous data, you can specify the criteria that will mark eye
blinks and eye movements.
The resulting information is stored in a threshold record, which is inaccessible to the
user.
Eye Blinks in Segmented or Continuous Data
To prevent bad eye channels from incorrectly influencing the marking of eye blinks,
the Perform Inferences section runs an algorithm that detects and discards segments
or samples with bad eye channels and then runs through the remaining data, marking
any threshold-violations as eye blinks.
If the Perform Inferences section cannot run because all the eye channels are bad, a
warning will appear.
If the Perform Inferences section cannot run because of bad inferior eye channels, a
dialog will appear, suggesting that you select the “Exclude inferior eye channels”
checkbox and run the tool again.
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