A reliability and validity study of an eye tracking system

The purpose was to investigate the reliability and validity of an eye tracking system, JAZZT from Ober Consulting, Poland, situated at FOI, Linköping. Furthermore, the inquiry was supposed to determine whether JAZZT could be a useful tool for detecting mental workload. Three different experiments were made on 17 subjects. Only horizontal saccades were studied, even though the equipment has several other features. The first experiment investigated the reliability and validity of the equipment, the second and third experiments were focused on mental workload. All three experiments were designed and controlled as test-retest, there were no external control group but all subject´s were their own controls. Subjective assessments were also a part of the inquiry. The subjects answered a questionnaire after each sub-experiment. The questions covered partly the comfort of the equipment and partly the experience of mental workload. Statistical results were calculated using ANOVA Repeated Measures in Statistica. The results showed that there were significant differences between the different experiments, and there were no such differences between the sub-experiments, which indicate that the equipment is reliable and valid. With the subjective measurements it was also shown that the equipment is able to detect mental workload.