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Parser Configuration

select_parser_configuration

select_parser_configuration = <set>

Selects the preset standard parser setup (0) or more sensitive saccade detector (1). These are equivalent to the cognitive and psychophysical configurations listed below. Note, users should use the select_parser_configuration to change the configuration in a group instead of modifying individual commands separately.

Arguments:

saccade_velocity_threshold

saccade_velocity_threshold = <vel>

Sets velocity threshold of saccade detector: usually 30 for cognitive research, 22 for pursuit and neurological work.

Arguments:

saccade_acceleration_threshold

saccade_acceleration_threshold = <accel>

Sets acceleration threshold of saccade detector: usually 9500 for cognitive research, 5000 for pursuit and neurological work.

Arguments:

saccade_motion_threshold

saccade_motion_threshold = <deg>

Sets a spatial threshold to shorten saccades. Usually 0.15 for cognitive research, 0 for pursuit and neurological work.

Arguments:

saccade_pursuit_fixup

saccade_pursuit_fixup = <maxvel>

Sets the maximum pursuit velocity accommodation by the saccade detector. Usually 60.

Arguments:

fixation_update_interval

fixation_update_interval = <time>

Normally set to 0 to disable fixation update events. Set to 50 or 100 msec. to produce updates for gaze-controlled interface applications.

Arguments:

fixation_update_accumulate

fixation_update_accumulate = <time>

Normally set to 0 to disable fixation update events. Set to 50 or 100 msec. to produce updates for gaze-controlled interface applications. Set to 4 to collect single sample rather than average position.

Arguments:

Typical Parser Configurations

In general, users should use select_parser_configuration rather than the other commands listed below. The Cognitive configuration is optimal for visual search and reading, and ignores most saccades smaller than 0.5 degrees. It is less sensitive to set up problems. The Pursuit configuration is designed to detect small (< 0.25 degrees) saccades, but may produce false saccades if participant setup is poor.

Cognitive Configuration:

recording_parse_type = GAZE
saccade_velocity_threshold = 30
saccade_acceleration_threshold = 9500
saccade_motion_threshold = 0.15
saccade_pursuit_fixup = 60
fixation_update_interval = 0

Pursuit and Neurological Configuration:

recording_parse_type = GAZE
saccade_velocity_threshold = 22
saccade_acceleration_threshold = 5000
saccade_motion_threshold = 0.0
saccade_pursuit_fixup = 60
fixation_update_interval = 0

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