method_ek {saccadr}

Extract saccades using an algorithm proposed by Engbert and Kliegl (2003) doi:10.1016/S0042-6989(03)00084-1

Description

Extract saccades using an algorithm proposed by Engbert and Kliegl (2003) doi:10.1016/S0042-6989(03)00084-1

Usage

method_ek(x, y, vel, acc, sample_rate, trial, options)

Arguments

x

Gaze x coordinate, _arbitrary units_ as threshold velocity is computed in units of standard deviation.

y

Gaze x coordinate, _arbitrary units_ as threshold velocity is computed in units of standard deviation.

vel

Velocity data.frame with columns x, y, amp.

acc

Acceleration data.frame with columns x, y, amp.

sample_rate

Sample rate in Hz.

trial

Trial id, so that trial borders are respected when computing velocity and saccades.

options

Named list with method options. See details for further information.

Details

Method options, please refer to Engbert and Kliegl (2003) for details on parameters and the rationale for default values.

• ek_velocity_threshold Velocity threshold for saccade detection in standard deviations. Defaults to 6.

• ek_sd_fun Function used to compute standard deviation for velocities. Defaults to sd_via_median_estimator, as per formula #2 in Engbert and Kliegl (2003). Can be replaced with mad, sd, etc.

• ek_minimal_duration_ms Minimal duration of a saccade in milliseconds. Defaults to 12.

• ek_minimal_separation_ms A minimal required time gap between saccades. Defaults to 12.

Value

logical vector marking samples that belong to saccades

See Also

extract_saccades

Examples

# Do not run this function directly, use extract_saccades() instead