Pupil preprocessing and baseline audit

This article focuses on pupil preprocessing and baseline-readiness checks.

Recommended order

1. inspect raw pupil coverage;
2. flag missingness and implausible values;
3. interpolate short gaps only when justified;
4. audit baseline coverage;
5. create baseline-corrected or change-score variables;
6. document preprocessing choices.

Example workflow

gap_qc <- audit_gazepoint_pupil_gaps(all_gaze)

pupil_flagged <- flag_gazepoint_pupil_hampel(
  all_gaze,
  pupil_col = 'pupil_diameter'
  )

pupil_interp <- interpolate_gazepoint_pupil_pchip(
  pupil_flagged,
  pupil_col = 'pupil_diameter'
  )

baseline_qc <- audit_gazepoint_pupil_baseline(
  pupil_interp,
  baseline_start = -0.500,
  baseline_end = 0
  )

reliability_qc <- audit_gazepoint_pupil_reliability(pupil_interp)

Reporting note

Baseline correction should be reported with the baseline window, minimum coverage rule, interpolation rule, excluded cases, and sensitivity checks.