Vers une utilisabilité spécifique des jeux vidéo ?

International audienceLes jeux vidéo (JV) sont des systèmes interactifs différents des applications informatiques classiques. Leurs spécificités, liées à leur caractère divertissant et à l'emploi d'environnements virtuels, impliquent une approche centrée-utilisateur particulière. Plusieurs auteurs ont proposé différentes adaptations de la définition et des critères classiques de l'utilisabilité pour les rendre applicables aux JV. D'autres ont proposé des modèles centrés sur le joueur plus éloignés de la notion habituelle d'utilisabilité. Différentes méthodes, qui nécessitent ou non la participation d'utilisateurs, sont actuellement utilisées pour évaluer l'utilisabilité des JV. Cependant, elles sont souvent inadaptées car non conçues spécifiquement à partir des JV. Deux pistes vers la définition d'une utilisabilité spécifique des JV sont envisagées. D'une part, de nouveaux modèles théoriques basées sur les caractéristiques particulières des JV pourraient être développés. D'autre part, des recommandations ergonomiques spécifiques directement utilisables par les concepteurs de JV devraient être créées et validées en utilisant les JV les plus typiques

Computer-simulated environment for training : challenge of efficacy evaluation

Computer-assisted instruction has been around for decades. There has been much speculation about the benefits of computer-mediated learning. Numerous applications have been developed in different domains incorporated with emerging technologies. In recently years, advanced technologies, such as Augmented Reality (AR) and Virtual Reality (VR), have received much attention in their potential of creating interactive learning experience for the users. However, related literature and empirical studies indicated that learning effects in computer-simulated environments or Virtual Environments (VEs) are not systematically tested. Furthermore, the performance and learning in computer-simulated learning environment need to be evaluated through more rigorous methods. This paper suggests that 1) the efficacy of VEs is subject to a close examination, not only in terms of how VE-based training systems are easy of use, but also in terms of how effective learning is; 2) evaluation of learning in computer simulated learning environments is required to be reconsidered in terms of theoretical basis and evaluation methodologies that are relevant to the measurement of training effectiveness in computer-simulated virtual learning environment. This paper explains on how learning can be assessed in VEs through the lens of training evaluation.<br /

Variations des stratégies d'anticipation visuelle en fonction de la règle dans un jeu vidéo

National audienceDans certains jeux vidéo, le joueur a besoin d'anticiper le mouvement d'objets, d'obstacles ou de cibles pour atteindre son but. Cependant, des recherches ont montré que les stratégies visuelles utilisées dans un environnement visuel dynamique variaient selon le but des individus. Le but de l'expérience exploratoire présentée dans cet article était de comparer les stratégies oculaires de participants jouant dans un même environnement de jeu nécessitant de l'anticipation visuelle selon deux règles du jeu différentes. Les deux règles du jeu vidéo utilisé consistaient soit à " éviter ", soit à " toucher " un maximum d'obstacles avec une balle. L'enregistrement des mouvements oculaires montre que l'anticipation est plus importante et le balayage de l'écran de jeu plus large quand les joueurs doivent éviter les obstacles que quand ils doivent les toucher. Les implications de ce résultat sur les stratégies oculaires optimales et la conception de jeux vidéo sont discutées

Systematic evaluation of a virtual environment-based training systems

This paper explores the application of three constructs that deemed to be essential to quantify virtual environments (VE) efficacy: cognitive, skill-based, and affective learning outcomes. The authors discuss the implementation of these constructs in a user-centered evaluation of a VE training system. By transforming both the conceptual and operational cohorts for training evaluation the authors illustrate the benefits of the development of a Multi-dimensional User-centered Systematic Training Evaluation (MUSTe) method for quantifying VEs efficacy. Importantly, MUSTe acknowledges the importance of combining holistic and analytical approaches in conducting systematic user-based evaluation. Furthermore, it also emphasizes that quantifying VEs efficacy must reflect the perception and preferences of the users rather than the imposition of efficacy on single measures of task outcome. An empirical study that applied MUSTe evaluation method in quantifying a VE training system efficacy provided valuable evidence of the theoretical construct and content validity of the method.<br /

Optimizing Usability Studies by Complementary Evaluation Methods

This paper examines combinations of complementary evaluation methods as a strategy for efficient usability problem discovery. A data set from an earlier study is re-analyzed, involving three evaluation methods applied to two virtual environment applications. Results of a mixed-effects logistic regression suggest that usability testing and inspection discover rather disjunctive sets of problems. A resampling analysis reveals that mixing inspection and usability testing sessions in equal parts finds 20% more problems with the same number of session

Evaluating Direct Pointing and Indirect Cursor Interactions with Fitts' Law in Stereoscopic Environments

The development of virtual environment research has reached the stage of human interaction with three-dimensional (3D) objects. In this study, Fitts' method was used to such interaction techniques in virtual environment, and the Fitts' law applicability in 3D virtual environment was also considered. The experiment included two modes of interaction: direct interaction and indirect interaction that utilize different techniques depending on how users interact with 3D objects. Both interaction techniques were conducted in three indexes of difficulties and three egocentric target distances (a distance from participant to target). Movement time and throughput were measured for each interaction technique. The results show that the direct pointing technique is more efficient for interaction with the targets close to the participant, while the indirect cursor technique may be a viable option for targets further away from participant. Throughputs were found to be significantly higher for the direct pointing technique compared to the indirect cursor technique. The results of the mean movement time were highly correlated with the targets' index of difficulty for all interaction techniques, supporting evidence that Fitts' law can be applied to the interactions in 3D virtual environment. Based on the results, developers of VE application may relate to these findings in designing proper users' interactions

Evaluating Direct Pointing and Indirect Cursor Interactions with Fitts' Law in Stereoscopic Environments

The development of virtual environment research has reached the stage of human interaction with three-dimensional (3D) objects. In this study, Fitts' method was used to such interaction techniques in virtual environment, and the Fitts' law applicability in 3D virtual environment was also considered. The experiment included two modes of interaction: direct interaction and indirect interaction that utilize different techniques depending on how users interact with 3D objects. Both interaction techniques were conducted in three indexes of difficulties and three egocentric target distances (a distance from participant to target). Movement time and throughput were measured for each interaction technique. The results show that the direct pointing technique is more efficient for interaction with the targets close to the participant, while the indirect cursor technique may be a viable option for targets further away from participant. Throughputs were found to be significantly higher for the direct pointing technique compared to the indirect cursor technique. The results of the mean movement time were highly correlated with the targets' index of difficulty for all interaction techniques, supporting evidence that Fitts' law can be applied to the interactions in 3D virtual environment. Based on the results, developers of VE application may relate to these findings in designing proper users' interactions

User-centered virtual environment design for virtual rehabilitation

<p>Abstract</p> <p>Background</p> <p>As physical and cognitive rehabilitation protocols utilizing virtual environments transition from single applications to comprehensive rehabilitation programs there is a need for a new design cycle methodology. Current human-computer interaction designs focus on usability without benchmarking technology within a user-in-the-loop design cycle. The field of virtual rehabilitation is unique in that determining the efficacy of this genre of computer-aided therapies requires prior knowledge of technology issues that may confound patient outcome measures. Benchmarking the technology (e.g., displays or data gloves) using healthy controls may provide a means of characterizing the "normal" performance range of the virtual rehabilitation system. This standard not only allows therapists to select appropriate technology for use with their patient populations, it also allows them to account for technology limitations when assessing treatment efficacy.</p> <p>Methods</p> <p>An overview of the proposed user-centered design cycle is given. Comparisons of two optical see-through head-worn displays provide an example of benchmarking techniques. Benchmarks were obtained using a novel vision test capable of measuring a user's stereoacuity while wearing different types of head-worn displays. Results from healthy participants who performed both virtual and real-world versions of the stereoacuity test are discussed with respect to virtual rehabilitation design.</p> <p>Results</p> <p>The user-centered design cycle argues for benchmarking to precede virtual environment construction, especially for therapeutic applications. Results from real-world testing illustrate the general limitations in stereoacuity attained when viewing content using a head-worn display. Further, the stereoacuity vision benchmark test highlights differences in user performance when utilizing a similar style of head-worn display. These results support the need for including benchmarks as a means of better understanding user outcomes, especially for patient populations.</p> <p>Conclusions</p> <p>The stereoacuity testing confirms that without benchmarking in the design cycle poor user performance could be misconstrued as resulting from the participant's injury state. Thus, a user-centered design cycle that includes benchmarking for the different sensory modalities is recommended for accurate interpretation of the efficacy of the virtual environment based rehabilitation programs.</p