Improving the Usability of Interactive Systems by Incorporating Design Thinking into the Engineering Process: Raising Computer Science Students’ Awareness of Quality versus Quantity in Ideation

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An adaptable scan-based text entry for mobile devices: Design, predictive modeling, and empirical evaluation

This paper presents a highly customizable assistive on-screen keyboard for mobile devices, which supports several text entry methods based on row-column and bisection scanning techniques. Text entry can be accomplished using a zone based touch screen interface and/or via hardware keypads, involving configurable input control which can range from single-switch solution up to 5-key design. Apart from the presentation of a novel user interface, the paper contributions are as follows: development of movement models for all scan-based methods involved in text entry solution, computation of related upper-bound text entry speed predictions, and empirical investigation of their validity. In order to assess model predictions, a specific instance of row-column scanning technique was juxtaposed to bisection scanning principle in a user study involving 16 participants. Methods are evaluated against text entry performance, required workload, and general usability attributes. Although theoretical models predicted higher entry speed for bisection scanning, the results obtained from experiment demonstrated the row-column technique as significantly more efficient. This outcome discrepancy is specifically discussed by putting emphasis on factors that affect identified relation.

Optimizing Human Performance in Mobile Text Entry

Although text entry on mobile phones is abundant, research strives to achieve desktop typing performance "on the go". But how can researchers evaluate new and existing mobile text entry techniques? How can they ensure that evaluations are conducted in a consistent manner that facilitates comparison? What forms of input are possible on a mobile device? Do the audio and haptic feedback options with most touchscreen keyboards affect performance? What influences users' preference for one feedback or another? Can rearranging the characters and keys of a keyboard improve performance? This dissertation answers these questions and more. The developed TEMA software allows researchers to evaluate mobile text entry methods in an easy, detailed, and consistent manner. Many in academia and industry have adopted it. TEMA was used to evaluate a typical QWERTY keyboard with multiple options for audio and haptic feedback. Though feedback did not have a significant effect on performance, a survey revealed that users' choice of feedback is influenced by social and technical factors. Another study using TEMA showed that novice users entered text faster using a tapping technique than with a gesture or handwriting technique. This motivated rearranging the keys and characters to create a new keyboard, MIME, that would provide better performance for expert users. Data on character frequency and key selection times were gathered and used to design MIME. A longitudinal user study using TEMA revealed an entry speed of 17 wpm and a total error rate of 1.7% for MIME, compared to 23 wpm and 5.2% for QWERTY. Although MIME's entry speed did not surpass QWERTY's during the study, it is projected to do so after twelve hours of practice. MIME's error rate was consistently low and significantly lower than QWERTY's. In addition, participants found MIME more comfortable to use, with some reporting hand soreness after using QWERTY for extended periods

Modèle théorique et outil de simulation pour une meilleure évaluation des claviers logiciels augmentés d'un système de prédiction de mots

Les claviers logiciels se sont démocratisés pour rendre possible la saisie de textes en mobilité sur des dispositifs dépourvus de claviers physiques tels que les téléphones portables nouvelle génération. Cependant, ces claviers présentent plusieurs inconvénients comme la lenteur de la saisie et la fatigue engendrées pour les utilisateurs déficients moteurs. La solution intuitive était d'allier ces logiciels à des listes contenant les mots susceptibles de continuer la saisie d'un mot initié par l'utilisateur. Bien que ces listes, dites listes de prédiction, réduisent le nombre de clics et le nombre d'opérations, la vitesse de saisie de l'utilisateur a diminué. Une expérimentation outillée d'un système de suivi du regard a ainsi permis de déterminer des " stratégies " de fonctionnement de l'utilisateur face à une liste de mots. Ces résultats ont ainsi permis d'affiner les modèles de prédiction de manière à réduire l'écart séparant les performances prédites des performances réellement enregistrées. A partir des constats effectués lors de la première expérimentation, nous proposons deux variantes de l'utilisation des listes de prédiction de mots. La première propose un nouveau moyen d'interagir avec la liste de mots et permet ainsi de maximiser l'utilisation de celle-ci. La seconde évalue un repositionnement de la liste de mots de manière à réduire le nombre de mouvements oculaires vers la liste. Ces deux évolutions, évaluées théoriquement puis au moyen d'une expérimentation utilisateur, permettent ainsi d'améliorer les performances de saisie par rapport à une liste de prédiction de mots classique.Predictive model and simulation tool for a best evaluation of soft keyboard augmented by words prediction list The software keyboards are used to enable text input in mobility and for devices without physical keyboards, such as the new generation of mobile phones. However, these keyboards have several drawbacks such as slowness text entry and fatigue generated for motor impaired users. The solution was to combine software keyboard to lists containing the words likely to continue the word introduced by the user. While these lists, so-called prediction lists, reduce the number of clicks and the number of operations, the speed of user input has decreased. An experiment with an eye tracking system has identified the "strategies" of the user while using and searching a list of words. These results were helpful to refine the prediction models in order to reduce the gap between the performance predicted and the performance actually recorded. Based on observations made during the first experiment, we propose two variants of the use of word prediction list. The first proposes a new way to interact with the list of words and allows maximum use of it. The second evaluates a repositioning of the list of words in order to reduce the number of eye movements to the list. These two propositions were theoretically and experimentally evaluated by users. These software can improve the input performances compared with a classic word prediction list

Investigating retrospective interoperability between the accessible and mobile webs with regard to user input

The World Wide Web (Web) has become a key technology to provide access to on-line information. The Mobile Web users, who access the Web using small devices such as mobile phones and Personal Digital Assistants (PDAs), make errors on entering text and controlling cursors. These errors are caused by both the characteristics of a device and the environment in which it is used, and are called situational impairments. Disabled Web users, on the other hand, have difficulties in accessing the Web due to their impairments in visual, hearing or motor abilities. We assert that errors experienced by the Mobile Web users share similarity in scope with those hindering motor-impaired Web users with dexterity issues, and existing solutions from the motor-impaired users domain can be migrated to the Mobile Web domain to address the common errors.Results of a systematic literature survey have revealed 12 error types that affect both the Mobile Web users and disabled Web users. These errors range from unable to locate a key to unable to pin-point a cursor. User experiments have confirmed that the Mobile Web users and motor-impaired Web users share errors in scope: they both miss key presses, press additional keys, unintentionally press a key more than once or press a key too long. In addition, both small device users and motor-impaired desktop users have difficulties in performing clicking, multiple clicking and drag selecting. Furthermore, when small device users are moving, both the scope and the magnitude of the errors are shared. In order to address these errors, we have migrated existing solutions from the disabled Web users domain into the Mobile Web users domain. We have developed a typing error correction system for the Mobile Web users. Results of the user evaluation have indicated that the proposed system can significantly reduce the error rates of the Mobile Web users.This work has an important contribution to both the Web accessibility field and the Mobile Web field. By leveraging research from the Web accessibility field into the Mobile Web field, we have linked two disjoint domains together. We have migrated solutions from one domain to another, and thus have improved the usability and accessibility of the Mobile Web.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Méthodologie et instrumentalisation pour la conception et l'évaluation des claviers logiciels

Avec l'expansion des dispositifs mobiles, l'efficacité de la saisie de texte est un défi de plus en plus important pour l'interaction homme-machine. Or, nous observons que, bien que les claviers type AZERTY ou téléphone, traditionnellement utilisés sur ces supports, soient évalués comme sous-optimaux, et, bien que de nombreuses alternatives évaluées comme plus performantes soient proposées dans la littérature, ces nouvelles alternatives restent très marginalement utilisées. Sur la base de cette observation, nous argumentons que la finalité des évaluations ne tient compte que d'un aspect du clavier, aspect qui n'est pas représentatif de la capacité d'un utilisateur à intégrer les concepts proposés dans son quotidien. Nous proposons en conséquence une stratégie complémentaire d'évaluation sur la base d'une évaluation heuristique des claviers logiciels. Par ailleurs, de manière à faciliter la mise en œuvre des évaluations et simplifier le design de nouveaux claviers, nous proposons une nouvelle version (E-Assist II) de la plate-forme E-Assiste. Elle permet, en premier lieu, de facilité le design et le déroulement des expérimentations, et plus largement d'encadrer les évaluations théoriques, expérimentales et heuristiques des claviers. Une version TinyEAssist permet également de déployer des expérimentations sur des supports mobiles (téléphones portables notamment). En second lieu, sur la base de l'étude de la structure des claviers logiciels, nous avons de plus proposé un langage de spécification des claviers permettant de générer des claviers logiciels complexes (interagissant potentiellement avec des systèmes de prédiction) à des fins d'expérimentation ou de simple usage. Enfin, sur la base des critères de performance mis en évidence par les évaluations heuristiques, nous proposons quatre nouveaux paradigmes de claviers. Parmi ces paradigmes deux ont offert des perspectives particulièrement intéressantes : en premier lieu le clavier multi-layer consistant à conduire progressivement, au cours d'une période transitoire, un utilisateur d'une distribution de touches type AZERTY vers une distribution de touches optimisée ; Le second consistant à faciliter l'accès aux caractères type accents, majuscules ou ponctuation, souvent déconsidérés dans l'optimisation des claviers logiciels.The expansion of mobile devices turn text input performances a major challenge for Human-Machine Interaction. We observed that, even if traditional QWERTY soft keyboards or telephone based soft keyboard were evaluated as poorly efficient, and, even if several alternatives evaluated as more efficient were proposed in the research field, these new alternatives are rarely used. Based on this observation, we argue that the goal of soft keyboard evaluation focus on long term performances whereas does not take into account the perspective for a user to use it in his quotidian. Consequently, we propose a complementary evaluation strategy base on heuristic evaluation methodology. In order to ease the evaluation and design of new soft keyboards, we proposed a new version (E-Assist II) of the E-Assiste plate-form. This plate-form aims, at first, to facilitate the design and procedure of experimentations and, more generally, to guide the theoretical, experimental and heuristic evaluations. A compact version (TinyEAssist) enables to perform experimentation on mobile environment such as mobile phone. At second, based on soft keyboard structure study, we proposed a keyboard specification language enabling to generate complex keyboard (including soft keyboard interacting with prediction systems). The generated soft keyboards may be used into the experimentation plate-form or interacting with the exploration system. At last, based on the criteria highlighted by the heuristic evaluation, we proposed four new soft keyboard paradigms. Among them two paradigms showed interesting perspectives: at first the multilayer keyboard consist in accompanying the user from a standard QWERTY layout to an optimized layout during a transition period; the second consist in accelerating the access to the characters such as accents, upper-case, punctuation, etc., frequently ignored in the keyboard optimizations

Alternative text entry using different input methods

This paper deals with PC-based alternative (i.e., keyboardfree) text entry and the issues related to emulating keystrokes with only a limited number of input signals. The previously introduced HaMCoS tool tries to enable someone who cannot use the hands to enter text almost as fast as someone exclusively using a manual mouse. To achieve this rather ambitious goal, HaMCoS provides two different (but combinable) solutions. On the one hand, word completion is offered as a shortcut technique. On the other hand, in addition to a mere on-screen keyboard, a completely new application has been implemented where selecting characters is somehow similar to entering Morse code (but with four ’bits ’ instead of dots and dashes only). In order to show the effect of these measures, the times needed to copy a moderately long text in various circumstances are reported. Categories and Subject Descriptors K.4.2 [Computers and Society]: Social Issues—Assistive technologies for persons with disabilities; H.5.2 [Informatio