Input device matters for measures of behaviour in online experiments

Area of Science:

• Cognitive Psychology
• Human-Computer Interaction
• Experimental Psychology

Background:

• Online experiments increasingly use cursor tracking for sensitive psychological measures.
• Experimenter control over participant input devices (mouse, trackpad) is limited.
• Mice and trackpads have distinct biomechanics, potentially affecting cursor data.

Purpose of the Study:

• To investigate how input device choice influences cursor tracking measures in online experiments.
• To identify specific kinematic measures affected by mouse versus trackpad use.
• To assess the risk of misinterpreting psychological differences due to input device artifacts.

Main Methods:

• Conducted two online experiments involving goal-directed movements.
• Utilized kinematic decomposition of cursor trajectories.
• Compared performance metrics between mouse and trackpad users.

Main Results:

• Trackpad users exhibited slower target acquisition, primarily due to longer movement initiation and clicking times.
• Despite slower acquisition, trackpad users showed higher peak movement speeds.
• Trackpad use resulted in lower movement variability compared to mouse use.

Conclusions:

• Input device choice significantly impacts cursor tracking data in online studies.
• Behavioral differences attributed to input devices may be erroneously interpreted as psychological variations.
• Researchers should record input device data and account for its influence on experimental results.