@article{ma_kaber_2007, title={Situation awareness and driving performance in a simulated navigation task}, volume={50}, ISSN={["1366-5847"]}, DOI={10.1080/00140130701318913}, abstractNote={This study investigated the effect of varying reliability of in-vehicle navigation aids on driver situation awareness (SA) and performance. Twenty participants drove a virtual car and navigated a large virtual suburb. Participants were required to follow traffic signs and navigation directions from one of two sources: a human aid via a cell phone or an automated aid presented on a laptop display. The aids operated under three different levels of reliability (100%, 80% and 60%). A control condition was also used in which each aid presented a telemarketing survey and participants navigated using a map. Results revealed perfect navigation information to improve driving performance and SA for strategic behaviors, as compared to unreliable information and the control condition. This work demonstrates in-vehicle automation may mediate linkages of levels of SA to specific driving behaviors and associated actions. This is represented through a transactional model of driver SA.}, number={8}, journal={ERGONOMICS}, author={Ma, R. and Kaber, D. B.}, year={2007}, month={Aug}, pages={1351–1364} }
 @article{ma_kaber_2006, title={Presence, workload and performance effects of synthetic environment design factors}, volume={64}, ISSN={["1095-9300"]}, DOI={10.1016/j.ijhcs.2005.12.003}, abstractNote={There remains a limited understanding of factors in presence and its relation to performance. This research examined a range of synthetic environment (SE) design features (viewpoint, auditory cue type and visual background) suspected to influence presence, and evaluated differences in presence, workload and task performance caused by manipulations of the factors and task difficulty in a virtual-reality-based basketball free-throw task. Thirty-two research participants were also required to perform secondary-monitoring tasks to assess attention allocation to the virtual and (surrounding) real environments, as an indicator of presence. Analysis of variance results demonstrated immersiveness (viewpoint) and auditory cue type to significantly influence the sense of subjective presence and perceptions of workload. Virtual task performance was significantly affected by task difficultly. This study also provided further evidence of significant positive relations between presence and workload, but no evidence of a correlation of objective presence and performance. These results have general applicability for the design of multimodal SE-based interfaces for real-world tasks, such as telerobot control.}, number={6}, journal={INTERNATIONAL JOURNAL OF HUMAN-COMPUTER STUDIES}, author={Ma, RQ and Kaber, DB}, year={2006}, month={Jun}, pages={541–552} }
 @article{ma_kaber_2005, title={Situation awareness and workload in driving while using adaptive cruise control and a cell phone}, volume={35}, ISSN={["1872-8219"]}, DOI={10.1016/j.ergon.2005.04.002}, abstractNote={Little work has empirically examined the cognitive construct of situation awareness (SA) in driving tasks involving the use of advanced in-vehicle automated technologies and personal communication devices. This research investigated the effects of an adaptive cruise control (ACC) system, and cell phone use in driving, on a direct and objective measure of SA, and assessed the competition of multiple driving and communication tasks for limited mental resources in terms of driving performance. Eighteen participants drove a virtual car in a driving simulation and performed a following task involving changes in speed and lateral position. Half of the participants were required to respond to cell phone calls and all completed trials with and without use of the ACC system. Task performance was measured in terms of lane deviations and speed control in tracking a lead vehicle, as well as headway distance in the following task. SA was measured using a simulation freeze technique and SA queries on the driving situation. Subjective workload was measured using a uni-dimensional mental workload rating. Results indicated use of the ACC system to improve driving task SA under typical driving conditions, and to reduce driver mental workload. However, the cell phone conversation caused deleterious effects on driving SA and increased driver mental load. The cell phone conversation (secondary task) competed for limited mental resources of drivers, leading to less attention to, and accurate knowledge of, the driving situation. Results also revealed the ACC system to improve driving performance along multiple dimensions; however, the cell phone did not have an effect. The latter result may be attributed to a short duration of the cell phone conversations during the experiment. This study has implications for the implementation of in-vehicle automation to support driver SA under normal driving conditions and regulations on the use of cell phones while driving. The results of this study have relevance to the introduction of advanced automation in commercial vehicles for supporting driver SA and regulation of cell phone use in driving. The study brings to light the critical role of attention-demanding distracter tasks, such as cell phone conversation while driving and using in-vehicle automation.}, number={10}, journal={INTERNATIONAL JOURNAL OF INDUSTRIAL ERGONOMICS}, author={Ma, RQ and Kaber, DB}, year={2005}, month={Oct}, pages={939–953} }