Keystroke-Level Model to Evaluate Chatbot Interface for Reservation System

The tour package reservation system is an important part of improving tourism services. Reservations must be able to meet the information needs of prospective customers and can serve the desired tour package bookings. A reservation system is usually a form that must be filled in sequence by prospective visitors. This paper discusses the evaluation of the application of the chatbot interface on the reservation system with the keystroke-level model. Changing the interaction design that previously did the task fills out the form into a conversation interaction. The aim is to increase the speed of the ordering process through the system. Prospective visitors do not need to fill in the form, they only need to have a conversation with the system while entering the order data. The evaluation results using the keystroke-level model show that the chatbot interface can increase the speed of the process by shortening steps

Адаптация модели GOMS для мобильных приложений

В статье освещается тенденция к всеобщей вовлечённости современного человечества в цифровой мир одновременно с высоким уровнем озабоченности собственным физическим и душевным комфортом. Данная проблема в том числе сегодня заставляет участников рынка не просто реализовывать свои продукты и услуги и даже не заводить сайты, а переходить к разработке мобильных приложений, которые будут всегда под рукой потребителя. Причём для обеспечения конкурентоспособности интерфейс этих приложений должен быть удобным и понятным. В связи с этой потребностью становится очевидной проблема недостатка методов тестирования мобильных устройств в целом и количественных методов в частности. Этой проблеме и уделяется основное внимание в статье. Приводятся примеры методов тестирования отдельно мобильных интерфейсов и комбинированных методов, разработанных изначально для десктопных устройств и впоследствии адаптированных под мобильные. Приводится определение одного из десктопных количественных методов – GOMS-анализа – и перечисляются его элементы. Также статья ссылается на ряд других методов-адаптаций GOMS, которые были предложены ранее другими авторами. Сделан вывод о несоответствии данных методов современным реалиям. Предложен вариант метода GOMS для мобильных приложений, включающий в себя все измеримые операторы, которые могут быть использованы при взаимодействии с мобильными приложениями посредством как сенсорных, так и кнопочных устройств. Продемонстрированы результаты эксперимента, демонстрирующие время выполнения операторов, которое можно использовать в качестве ориентира при проведении тестирований и дальнейших исследований на эту тему

Integrating Usability Models into Pervasive Application Development

This thesis describes novel processes in two important areas of human-computer interaction (HCI) and demonstrates ways to combine these in appropriate ways. First, prototyping plays an essential role in the development of complex applications. This is especially true if a user-centred design process is followed. We describe and compare a set of existing toolkits and frameworks that support the development of prototypes in the area of pervasive computing. Based on these observations, we introduce the EIToolkit that allows the quick generation of mobile and pervasive applications, and approaches many issues found in previous works. Its application and use is demonstrated in several projects that base on the architecture and an implementation of the toolkit. Second, we present novel results and extensions in user modelling, specifically for predicting time to completion of tasks. We extended established concepts such as the Keystroke-Level Model to novel types of interaction with mobile devices, e.g. using optical markers and gestures. The design, creation, as well as a validation of this model are presented in some detail in order to show its use and usefulness for making usability predictions. The third part is concerned with the combination of both concepts, i.e. how to integrate user models into the design process of pervasive applications. We first examine current ways of developing and show generic approaches to this problem. This leads to a concrete implementation of such a solution. An innovative integrated development environment is provided that allows for quickly developing mobile applications, supports the automatic generation of user models, and helps in applying these models early in the design process. This can considerably ease the process of model creation and can replace some types of costly user studies.Diese Dissertation beschreibt neuartige Verfahren in zwei wichtigen Bereichen der Mensch-Maschine-Kommunikation und erläutert Wege, diese geeignet zu verknüpfen. Zum einen spielt die Entwicklung von Prototypen insbesondere bei der Verwendung von benutzerzentrierten Entwicklungsverfahren eine besondere Rolle. Es werden daher auf der einen Seite eine ganze Reihe vorhandener Arbeiten vorgestellt und verglichen, die die Entwicklung prototypischer Anwendungen speziell im Bereich des Pervasive Computing unterstützen. Ein eigener Satz an Werkzeugen und Komponenten wird präsentiert, der viele der herausgearbeiteten Nachteile und Probleme solcher existierender Projekte aufgreift und entsprechende Lösungen anbietet. Mehrere Beispiele und eigene Arbeiten werden beschrieben, die auf dieser Architektur basieren und entwickelt wurden. Auf der anderen Seite werden neue Forschungsergebnisse präsentiert, die Erweiterungen von Methoden in der Benutzermodellierung speziell im Bereich der Abschätzung von Interaktionszeiten beinhalten. Mit diesen in der Dissertation entwickelten Erweiterungen können etablierte Konzepte wie das Keystroke-Level Model auf aktuelle und neuartige Interaktionsmöglichkeiten mit mobilen Geräten angewandt werden. Der Entwurf, das Erstellen sowie eine Validierung der Ergebnisse dieser Erweiterungen werden detailliert dargestellt. Ein dritter Teil beschäftigt sich mit Möglichkeiten die beiden beschriebenen Konzepte, zum einen Prototypenentwicklung im Pervasive Computing und zum anderen Benutzermodellierung, geeignet zu kombinieren. Vorhandene Ansätze werden untersucht und generische Integrationsmöglichkeiten beschrieben. Dies führt zu konkreten Implementierungen solcher Lösungen zur Integration in vorhandene Umgebungen, als auch in Form einer eigenen Applikation spezialisiert auf die Entwicklung von Programmen für mobile Geräte. Sie erlaubt das schnelle Erstellen von Prototypen, unterstützt das automatische Erstellen spezialisierter Benutzermodelle und ermöglicht den Einsatz dieser Modelle früh im Entwicklungsprozess. Dies erleichtert die Anwendung solcher Modelle und kann Aufwand und Kosten für entsprechende Benutzerstudien einsparen

Investigating Performance and Usage of Input Methods for Soft Keyboard Hotkeys

Touch-based devices, despite their mainstream availability, do not support a unified and efficient command selection mechanism, available on every platform and application. We advocate that hotkeys, conventionally used as a shortcut mechanism on desktop computers, could be generalized as a command selection mechanism for touch-based devices, even for keyboard-less applications. In this paper, we investigate the performance and usage of soft keyboard shortcuts or hotkeys (abbreviated SoftCuts) through two studies comparing different input methods across sitting, standing and walking conditions. Our results suggest that SoftCuts not only are appreciated by participants but also support rapid command selection with different devices and hand configurations. We also did not find evidence that walking deters their performance when using the Once input method.Comment: 17+2 pages, published at Mobile HCI 202

Shortlinks and tiny keyboards: a systematic exploration of design trade-offs in link shortening services

Link-shortening services save space and make the manual entry of URLs less onerous. Short links are often included on printed materials so that people using mobile devices can quickly enter URLs. Although mobile transcription is a common use-case, link-shortening services generate output that is poorly suited to entry on mobile devices: links often contain numbers and capital letters that require time consuming mode switches on touch screen keyboards. With the aid of computational modeling, we identified problems with the output of a link-shortening service, bit.ly. Based on the results of this modeling, we hypothesized that longer links that are optimized for input on mobile keyboards would improve link entry speeds compared to shorter links that required keyboard mode switches. We conducted a human performance study that confirmed this hypothesis. Finally, we applied our method to a selection of different non-word mobile data-entry tasks. This work illustrates the need for service design to fit the constraints of the devices people use to consume services

Learning from Interaction: User Interface Adaptation using Reinforcement Learning

The continuous adaptation of software systems to meet the evolving needs of users is very important for enhancing user experience (UX). User interface (UI) adaptation, which involves adjusting the layout, navigation, and content presentation based on user preferences and contextual conditions, plays an important role in achieving this goal. However, suggesting the right adaptation at the right time and in the right place remains a challenge in order to make it valuable for the end-user. To tackle this challenge, machine learning approaches could be used. In particular, we are using Reinforcement Learning (RL) due to its ability to learn from interaction with the users. In this approach, the feedback is very important and the use of physiological data could be benefitial to obtain objective insights into how users are reacting to the different adaptations. Thus, in this PhD thesis, we propose an RL-based UI adaptation framework that uses physiological data. The framework aims to learn from user interactions and make informed adaptations to improve UX. To this end, our research aims to answer the following questions: Does the use of an RL-based approach improve UX? How effective is RL in guiding UI adaptation? and Can physiological data support UI adaptation for enhancing UX? The evaluation plan involves conducting user studies to evaluate answer these questions. The empirical evaluation will provide a strong empirical foundation for building, evaluating, and improving the proposed adaptation framework. The expected contributions of this research include the development of a novel framework for intelligent Adaptive UIs, insights into the effectiveness of RL algorithms in guiding UI adaptation, the integration of physiological data as objective measures of UX, and empirical validation of the proposed framework's impact on UX

Conservation of Limited Resources: Design Principles for Security and Usability on Mobile Devices

Mobile devices have evolved from an accessory to the primary computing device for an increasing portion of the general population. Not only is mobile the primary device, consumers on average have multiple Internet-connected devices. The trend towards mobile has resulted in a shift to “mobile-first” strategies for delivering information and services in business organizations, universities, and government agencies. Though principles for good security design exist, those principles were formulated based upon the traditional workstation configuration instead of the mobile platform. Security design needs to follow the shift to a “mobile-first” emphasis to ensure the usability of the security interface. The mobile platform has constraints on resources that can adversely impact the usability of security. This research sought to identify design principles for usable security for mobile devices that address the constraints of the mobile platform. Security and usability have been seen as mutually exclusive. To accurately identify design principles, the relationship between principles for good security design and usability design must be understood. The constraints for the mobile environment must also be identified, and then evaluated for their impact on the interaction of a consumer with a security interface. To understand how the application of the proposed mobile security design principles is perceived by users, an artifact was built to instantiate the principles. Through a series of guided interactions, the importance of proposed design principles was measured in a simulation, in human-computer interaction, and in user perception. The measures showed a resounding difference between the usability of the same security design delivered on mobile vs. workstation platform. It also reveals that acknowledging the constraints of an environment and compensating for the constraints yields mobile security that is both usable and secure. Finally, the hidden cost of security design choices that distract the user from the surrounding environment were examined from both the security perspective and public safety perspective

The effects of individual differences on mobile phone users’ operational behaviour

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Mobile handset technology has improved greatly in recent decades. Improvements in hardware and software conduce the importance of the handset as a computer. Whilst the mobile phone industry and researchers emphasise understanding users from sociological aspects, such as services, usage habits, functionalities and so forth; this research aims to seek the variables that impact upon users’ interactions with the phone from the root-individual differences. For the purpose of placing mobile phone users at the core of the interface design process, the individual differences of gender, cognitive style and user experience were applied as the main variables in this research. Accordingly, to examine individuals’ differences and their operational behaviour with phone interfaces, the effects of cognitive style and user experience present stronger impact on the user performance than gender. The two factors were then investigated with regard to individuals’ operational behaviour with phone interfaces. This research then developed categories to link the theoretical attributes of cognitive style and phone users’ practical operational behaviour. Furthermore, the impact of cognitive style on the users’ operational behaviour was also connected to individuals’ problem solving ability. Meanwhile, the effect of user experience was investigated with a novel methodology-Taxonomy of Experience. The results revealed necessary elements that the users cared about the most, and these differed from the interface design guidelines of phone industry. This PhD thesis presents the application of the triangulation method to explore the variables that impact upon individuals’ interaction with mobile phone interfaces, specially concerned with mobile phone interface design from a psychological perspective, and provides a deeper understanding of users for future design events. More importantly, this research delivered the concept of understanding users before conducting design

Supporting the Development Process of Multimodal and Natural Automotive User Interfaces

Nowadays, driving a car places multi-faceted demands on the driver that go beyond maneuvering a vehicle through road traffic. The number of additional functions for entertainment, infotainment and comfort increased rapidly in the last years. Each new function in the car is designed to make driving as pleasant as possible but also increases the risk that the driver will be distracted from the primary driving task. One of the most important goals for designers of new and innovative automotive user interfaces is therefore to keep driver distraction to a minimum while providing an appropriate support to the driver. This goal can be achieved by providing tools and methods that support a human-centred development process. In this dissertation, a design space will be presented that helps to analyze the use of context, to generate new ideas for automotive user interfaces and to document them. Furthermore, new opportunities for rapid prototyping will be introduced. To be able to evaluate new automotive user interfaces and interaction concepts regarding their effect on driving performance, a driving simulation software was developed within the scope of this dissertation. In addition, research results in the field of multimodal, implicit and eye-based interaction in the car are presented. The different case studies mentioned illustrate the systematic and comprehensive research on the opportunities of these kinds of interaction, as well as their effects on driving performance. We developed a prototype of a vibration steering wheel that communicates navigation instructions. Another prototype of a steering wheel has a display integrated in the middle and enables handwriting input. A further case study explores a visual placeholder concept to assist drivers when using in-car displays while driving. When a driver looks at a display and then at the street, the last gaze position on the display is highlighted to assist the driver when he switches his attention back to the display. This speeds up the process of resuming an interrupted task. In another case study, we compared gaze-based interaction with touch and speech input. In the last case study, a driver-passenger video link system is introduced that enables the driver to have eye contact with the passenger without turning his head. On the whole, this dissertation shows that by using a new human-centred development process, modern interaction concepts can be developed in a meaningful way.Das Führen eines Fahrzeuges stellt heute vielfältige Ansprüche an den Fahrer, die über das reine Manövrieren im Straßenverkehr hinausgehen. Die Fülle an Zusatzfunktionen zur Unterhaltung, Navigation- und Komfortzwecken, die während der Fahrt genutzt werden können, ist in den letzten Jahren stark angestiegen. Einerseits dient jede neu hinzukommende Funktion im Fahrzeug dazu, das Fahren so angenehm wie möglich zu gestalten, birgt aber anderseits auch immer das Risiko, den Fahrer von seiner primären Fahraufgabe abzulenken. Eines der wichtigsten Ziele für Entwickler von neuen und innovativen Benutzungsschnittstellen im Fahrzeug ist es, die Fahrerablenkung so gering wie möglich zu halten und dabei dem Fahrer eine angemessene Unterstützung zu bieten. Werkzeuge und Methoden, die einen benutzerzentrierten Entwicklungsprozess unter-stützen, können helfen dieses Ziel zu erreichen. In dieser Dissertation wird ein Entwurfsraum vorgestellt, welcher helfen soll den Benutzungskontext zu analysieren, neue Ideen für Benutzungsschnittstellen zu generieren und diese zu dokumentieren. Darüber hinaus wurden im Rahmen der Arbeit neue Möglichkeiten zur schnellen Prototypenerstellung entwickelt. Es wurde ebenfalls eine Fahrsimulationssoftware erstellt, welche die quantitative Bewertung der Auswirkungen von Benutzungs-schnittstellen und Interaktionskonzepten auf die Fahreraufgabe ermöglicht. Desweiteren stellt diese Dissertation neue Forschungsergebnisse auf den Gebieten der multimodalen, impliziten und blickbasierten Interaktion im Fahrzeug vor. In verschiedenen Fallbeispielen wurden die Möglichkeiten dieser Interaktionsformen sowie deren Auswirkung auf die Fahrerablenkung umfassend und systematisch untersucht. Es wurde ein Prototyp eines Vibrationslenkrads erstellt, womit Navigations-information übermittelt werden können sowie ein weiterer Prototyp eines Lenkrads, welches ein Display in der Mitte integriert hat und damit handschriftliche Texteingabe ermöglicht. Ein visuelles Platzhalterkonzept ist im Fokus eines weiteren Fallbeispiels. Auf einem Fahrzeugdisplay wird die letzte Blickposition bevor der Fahrer seine Aufmerksamkeit dem Straßenverkehr zuwendet visuell hervorgehoben. Dies ermöglicht dem Fahrer eine unterbrochene Aufgabe z.B. das Durchsuchen einer Liste von Musik-titel schneller wieder aufzunehmen, wenn er seine Aufmerksamkeit wieder dem Display zuwendet. In einer weiteren Studie wurde blickbasierte Interaktion mit Sprach- und Berührungseingabe verglichen und das letzte Fallbeispiel beschäftigt sich mit der Unterstützung der Kommunikation im Fahrzeug durch die Bereitstellung eines Videosystems, welches Blickkontakt zwischen dem Fahrer und den Mitfahrern ermöglicht, ohne dass der Fahrer seinen Kopf drehen muss. Die Arbeit zeigt insgesamt, dass durch den Einsatz eines neuen benutzerzentrierten Entwicklungsprozess moderne Interaktionskonzept sinnvoll entwickelt werden können