A Usability Inspection Method for Model-driven Web Development Processes

Las aplicaciones Web son consideradas actualmente un elemento esencial e indispensable en toda actividad empresarial, intercambio de información y motor de redes sociales. La usabilidad, en este tipo de aplicaciones, es reconocida como uno de los factores clave más importantes, puesto que la facilidad o dificultad que los usuarios experimentan con estas aplicaciones determinan en gran medida su éxito o fracaso. Sin embargo, existen varias limitaciones en las propuestas actuales de evaluación de usabilidad Web, tales como: el concepto de usabilidad sólo se soporta parcialmente, las evaluaciones de usabilidad se realizan principalmente cuando la aplicación Web se ha desarrollado, hay una carencia de guías sobre cómo integrar adecuadamente la usabilidad en el desarrollo Web, y también existe una carencia de métodos de evaluación de la usabilidad Web que hayan sido validados empíricamente. Además, la mayoría de los procesos de desarrollo Web no aprovechan los artefactos producidos en las fases de diseño. Estos artefactos software intermedios se utilizan principalmente para guiar a los desarrolladores y para documentar la aplicación Web, pero no para realizar evaluaciones de usabilidad. Dado que la trazabilidad entre estos artefactos y la aplicación Web final no está bien definida, la realización de evaluaciones de usabilidad de estos artefactos resulta difícil. Este problema se mitiga en el desarrollo Web dirigido por modelos (DWDM), donde los artefactos intermedios (modelos) que representan diferentes perspectivas de una aplicación Web, se utilizan en todas las etapas del proceso de desarrollo, y el código fuente final se genera automáticamente a partir estos modelos. Al tener en cuenta la trazabilidad entre estos modelos, la evaluación de estos modelos permite detectar problemas de usabilidad que experimentaran los usuarios finales de la aplicación Web final, y proveer recomendaciones para corregir estos problemas de usabilidad durante fases tempranas del proceso de desarrollo Web. Esta tesis tiene como objetivo, tratando las anteriores limitaciones detectadas, el proponer un método de inspección de usabilidad que se puede integrar en diferentes procesos de desarrollo Web dirigido por modelos. El método se compone de un modelo de usabilidad Web que descompone el concepto de usabilidad en sub-características, atributos y métricas genéricas, y un proceso de evaluación de usabilidad Web (WUEP), que proporciona directrices sobre cómo el modelo de usabilidad se puede utilizar para llevar a cabo evaluaciones específicas. Las métricas genéricas del modelo de usabilidad deben operacionalizarse con el fin de ser aplicables a los artefactos software de diferentes métodos de desarrollo Web y en diferentes niveles de abstracción, lo que permite evaluar la usabilidad en varias etapas del proceso de desarrollo Web, especialmente en las etapas tempranas. Tanto el modelo de usabilidad como el proceso de evaluación están alineados con la última norma ISO/IEC 25000 estándar para la evaluación de la calidad de productos de software (SQuaRE). El método de inspección de usabilidad propuesto (WUEP) se ha instanciado en dos procesos de desarrollo Web dirigido por modelos diferentes (OO-H y WebML) a fin de demostrar la factibilidad de nuestra propuesta. Además, WUEP fue validado empíricamente mediante la realización de una familia de experimentos en OO-H y un experimento controlado en WebML. El objetivo de nuestros estudios empíricos fue evaluar la efectividad, la eficiencia, facilidad de uso percibida y la satisfacción percibida de los participantes; cuando utilizaron WUEP en comparación con un método de inspección industrial ampliamente utilizado: La Evaluación Heurística (HE). El análisis estadístico y meta-análisis de los datos obtenidos por separado de cada experimento indicaron que WUEP es más eficaz y eficiente que HE en la detección de problemas de usabilidad. Los evaluadores también percibieron más satisfacción cuando se aplicaron WUEP, y lesFernández Martínez, A. (2012). A Usability Inspection Method for Model-driven Web Development Processes [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/17845Palanci

Understanding and Evaluating User Interface Visibility

Technology dominates our lives, mobile technology in particular. In 2016 Apple sold their billionth iPhone. By 2018 they had sold their 2 billionth device based on the same underlying operating system. We access such technology through the user interface (UI) and concerns have been raised about the usability of such devices. The situation has been described by some as a “usability crisis”. One of the key issues raised is the lack of visibility of user interface elements, which is deemed to be a critical component of an effective UI. An initial investigation highlighted that UI visibility can be broken down into three key aspects: Firstly; some user interface elements are effectively ‘missing’; Secondly, they are ‘missed’ because they are not seen by the user; and thirdly, they are seen but ‘misunderstood’. Further analysis of the home screen of an iPhone revealed that only 8% of the available functions were visible at the top level, in other words, 92% were effectively ‘missing’. This raises key questions about how UI visibility can be evaluated, and such evaluation adopted into design practice. This research took a psychophysical perspective to better understand UI visibility. This led to the development of an evaluation framework and associated tool called vis-UI-lise. The tool represents UI visibility as a series of 5 hurdles between the user and the interface that have to be overcome for a successful interaction. This tool was applied to an everyday task on a mobile phone which resulted in highlighting a range of possible usability problems. Comparison of the predicted versus observed problems showed that the vis-UI-lise tool had predicted 74% of them, a score that compares well with other usability evaluation tools. A training and support package was also developed for the vis-UI-lise tool and evaluated with four different organisations. This provided key insights into how the tool could be improved to fit in with typical design practice. This thesis brings a new perspective to the understanding and evaluation of UI visibility that could have a real impact on the design of everyday user interfaces

Perception of Unstructured Environments for Autonomous Off-Road Vehicles

Autonome Fahrzeuge benötigen die Fähigkeit zur Perzeption als eine notwendige Voraussetzung für eine kontrollierbare und sichere Interaktion, um ihre Umgebung wahrzunehmen und zu verstehen. Perzeption für strukturierte Innen- und Außenumgebungen deckt wirtschaftlich lukrative Bereiche, wie den autonomen Personentransport oder die Industrierobotik ab, während die Perzeption unstrukturierter Umgebungen im Forschungsfeld der Umgebungswahrnehmung stark unterrepräsentiert ist. Die analysierten unstrukturierten Umgebungen stellen eine besondere Herausforderung dar, da die vorhandenen, natürlichen und gewachsenen Geometrien meist keine homogene Struktur aufweisen und ähnliche Texturen sowie schwer zu trennende Objekte dominieren. Dies erschwert die Erfassung dieser Umgebungen und deren Interpretation, sodass Perzeptionsmethoden speziell für diesen Anwendungsbereich konzipiert und optimiert werden müssen. In dieser Dissertation werden neuartige und optimierte Perzeptionsmethoden für unstrukturierte Umgebungen vorgeschlagen und in einer ganzheitlichen, dreistufigen Pipeline für autonome Geländefahrzeuge kombiniert: Low-Level-, Mid-Level- und High-Level-Perzeption. Die vorgeschlagenen klassischen Methoden und maschinellen Lernmethoden (ML) zur Perzeption bzw.~Wahrnehmung ergänzen sich gegenseitig. Darüber hinaus ermöglicht die Kombination von Perzeptions- und Validierungsmethoden für jede Ebene eine zuverlässige Wahrnehmung der möglicherweise unbekannten Umgebung, wobei lose und eng gekoppelte Validierungsmethoden kombiniert werden, um eine ausreichende, aber flexible Bewertung der vorgeschlagenen Perzeptionsmethoden zu gewährleisten. Alle Methoden wurden als einzelne Module innerhalb der in dieser Arbeit vorgeschlagenen Perzeptions- und Validierungspipeline entwickelt, und ihre flexible Kombination ermöglicht verschiedene Pipelinedesigns für eine Vielzahl von Geländefahrzeugen und Anwendungsfällen je nach Bedarf. Low-Level-Perzeption gewährleistet eine eng gekoppelte Konfidenzbewertung für rohe 2D- und 3D-Sensordaten, um Sensorausfälle zu erkennen und eine ausreichende Genauigkeit der Sensordaten zu gewährleisten. Darüber hinaus werden neuartige Kalibrierungs- und Registrierungsansätze für Multisensorsysteme in der Perzeption vorgestellt, welche lediglich die Struktur der Umgebung nutzen, um die erfassten Sensordaten zu registrieren: ein halbautomatischer Registrierungsansatz zur Registrierung mehrerer 3D~Light Detection and Ranging (LiDAR) Sensoren und ein vertrauensbasiertes Framework, welches verschiedene Registrierungsmethoden kombiniert und die Registrierung verschiedener Sensoren mit unterschiedlichen Messprinzipien ermöglicht. Dabei validiert die Kombination mehrerer Registrierungsmethoden die Registrierungsergebnisse in einer eng gekoppelten Weise. Mid-Level-Perzeption ermöglicht die 3D-Rekonstruktion unstrukturierter Umgebungen mit zwei Verfahren zur Schätzung der Disparität von Stereobildern: ein klassisches, korrelationsbasiertes Verfahren für Hyperspektralbilder, welches eine begrenzte Menge an Test- und Validierungsdaten erfordert, und ein zweites Verfahren, welches die Disparität aus Graustufenbildern mit neuronalen Faltungsnetzen (CNNs) schätzt. Neuartige Disparitätsfehlermetriken und eine Evaluierungs-Toolbox für die 3D-Rekonstruktion von Stereobildern ergänzen die vorgeschlagenen Methoden zur Disparitätsschätzung aus Stereobildern und ermöglichen deren lose gekoppelte Validierung. High-Level-Perzeption konzentriert sich auf die Interpretation von einzelnen 3D-Punktwolken zur Befahrbarkeitsanalyse, Objekterkennung und Hindernisvermeidung. Eine Domänentransferanalyse für State-of-the-art-Methoden zur semantischen 3D-Segmentierung liefert Empfehlungen für eine möglichst exakte Segmentierung in neuen Zieldomänen ohne eine Generierung neuer Trainingsdaten. Der vorgestellte Trainingsansatz für 3D-Segmentierungsverfahren mit CNNs kann die benötigte Menge an Trainingsdaten weiter reduzieren. Methoden zur Erklärbarkeit künstlicher Intelligenz vor und nach der Modellierung ermöglichen eine lose gekoppelte Validierung der vorgeschlagenen High-Level-Methoden mit Datensatzbewertung und modellunabhängigen Erklärungen für CNN-Vorhersagen. Altlastensanierung und Militärlogistik sind die beiden Hauptanwendungsfälle in unstrukturierten Umgebungen, welche in dieser Arbeit behandelt werden. Diese Anwendungsszenarien zeigen auch, wie die Lücke zwischen der Entwicklung einzelner Methoden und ihrer Integration in die Verarbeitungskette für autonome Geländefahrzeuge mit Lokalisierung, Kartierung, Planung und Steuerung geschlossen werden kann. Zusammenfassend lässt sich sagen, dass die vorgeschlagene Pipeline flexible Perzeptionslösungen für autonome Geländefahrzeuge bietet und die begleitende Validierung eine exakte und vertrauenswürdige Perzeption unstrukturierter Umgebungen gewährleistet

Mobile flight and hotel booking application: A heuristic and UX test

The purpose of this study is to present the usability evaluation of the mobile flight and hotel booking application. Currently, mobile applications have offered the easiness to users in order to book flight and hotel. Unfortunately, there is a lack of study on usability that focuses on mobile booking application, while many people start to do all the transactions on their mobile phone.This study will conduct two combined usability evaluation methods which are heuristic and UX test.Ticket.com will be evaluated as it is a critical application that can represent the study of this usability testing.Those selected usability evaluation methods are to evaluate mobile application based on usability experts and end users to get feedbacks and propose solutions and recommendations to improve the application. Observation and questionnaire will be used to measure the metric of effectiveness, efficiency and satisfaction.The heuristic is conducted by three usability experts. Whereas, the UX test participants are ten persons that will be randomly selected either from novice users or the one who experience purchasing flight ticket and hotel reservation on mobile.The result of the study revealed that the application is not easy-to-use and inconsistent as it has been proven by usability score of this application is 66% or below average. It is expected that this study can be adopted by developers and usability practitioners to deliver a user-friendly mobile application that leads to high customer satisfaction

Development and validation of a new methodological platform to measure behavioral, cognitive, and physiological responses to food interventions in real time

To fully understand the causes and mechanisms involved in overeating and obesity, measures of both cognitive and physiological determinants of eating behavior need to be integrated. Effectively synchronizing behavioral measures such as meal micro-structure (e.g., eating speed), cognitive processing of sensory stimuli, and metabolic parameters, can be complex. However, this step is central to understanding the impact of food interventions on body weight. In this paper, we provide an overview of the existing gaps in eating behavior research and describe the development and validation of a new methodological platform to address some of these issues. As part of a controlled trial, 76 men and women self-served and consumed food from a buffet, using a portion-control plate with visual stimuli for appropriate amounts of main food groups, or a conventional plate, on two different days, in a random order. In both sessions participants completed behavioral and cognitive tests using a novel methodological platform that measured gaze movement (as a proxy for visual attention), eating rate and bite size, memory for portion sizes, subjective appetite and portion-size perceptions. In a sub-sample of women, hormonal secretion in response to the meal was also measured. The novel platform showed a significant improvement in meal micro-structure measures from published data (13 vs. 33% failure rate) and high comparability between an automated gaze mapping protocol vs. manual coding for eye-tracking studies involving an eating test (ICC between methods 0.85; 90% CI 0.74, 0.92). This trial was registered at Clinical Trials.gov with Identifier NCT03610776. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.3758/s13428-021-01745-9

Generating a domain-specific inspection method through an adaptive framework

Many recent innovations and inventions have contributed to rapid technological development, which in turn have produced a wide variety of products that have had a major impact on many businesses in several different domains. These products have their own contextual attributes that have made their usability evaluation, by using traditional usability evaluation methods (UEMs), all the more critical. Almost all previous usability studies have used the Heuristic Evaluation (HE) and User Testing (UT) methods; however, the majority of such studies have described these methods as being not directly applicable to the product being tested, not directly related to the context of the tested product, and not able to identify specific areas and types of usability problems. Furthermore, the lack of a methodological framework that can be used systematically to generate a domain-specific inspection method, which can then be used to assess the usability for a product in any chosen domain and to improve the usability assessment process, represents a missing area in usability testing. Thus, the goal of this research is to generate a domain-specific inspection evaluation method that does not involve users in an actual testing session, i.e. one that is applied by only experts. To reach this goal, firstly, a systematic adaptive framework is presented, called Domain Specific Inspection (DSI), which is characterized as being pertinent to the context and specific target of a chosen domain. This framework is designed to generate a method that avoids the drawbacks of having to use both HE and UT, although it combines their advantages. In addition, this framework assists researchers as it combines feedback from both expert evaluators and potential users in the chosen domain in order to create a focused method. Secondly, this research seeks to validate the adaptive framework practically by generating a DSI method for assessing the usability of selected products. In this regard, websites are chosen as the targeted product, and two experiments are conducted; the first examines the utility of the generated DSI method on the educational domain. The second examines another generated DSI method on the social network domain. In both experiments, the DSI methods are tested intensively through rigorous validation methods and a number of usability metrics to verify the extent to which it achieves the identified goals, needs and requirements that the methods were originally developed to address, and to identify which problems are identified by UT but not identified by HE and/or DSI, and vice versa. Also, an investigation into whether it is essential to conduct the DSI method in conjunction with UT or HE will be undertaken. Furthermore, the roles and numbers of evaluators (together with their types) and users will be examined. The results show that the adaptive framework is able to generate a DSI method that can be used to generate ideas from the different perspectives of multidisciplinary teams in order to create engaging user experiences and to facilitate interactive design. This method enables the discovery of a larger number of serious problems than UT and HE. In addition, it provides optimal results with regard to the identification of comprehensive usability problem areas, and it is more efficient and effective than UT and HE, with minimum input in terms of cost and time. Furthermore, it is able to improve the evaluator performance; thus, the results of the single evaluators, who used the DSI method, provided results that approached or outperformed the effectiveness of the double evaluators, who used HE. Consequently, few evaluators are needed to find a majority of the usability problems if DSI is used

Implications of Applying Usability Testing with Remote Users

Some studies in the literature on remote asynchronous usability testing have indicated the existence of contextual factors related to remote-uncontrolled environments. Typically, in these environments, users take part in the usability test at any time although uncontrolled contextual factors might be present. Moreover, such settings might induce different interactions with the evaluated products, which consequently may influence the data collected in the usability test. Therefore, this research aims to explore these kinds of interactions to determine whether they differ from users’ interactions in the laboratory and, if so, how. The findings of this research are intended to contribute new knowledge about the implications of applying asynchronous usability testing to remote users. To meet this goal, three main studies are conducted: the first exploratory study is aimed at exploring what happens during testing sessions in users’ natural environments. The second empirical study involves two participant samples: one sample performed the test in their natural environment, and the other sample performed the text in a lab. The performances of both groups are compared to explore their differences. User-reported data regarding contextual factors are also explored. In the third controlled experimental study, stimulating contextual factors are applied during usability testing sessions to explore the users’ interactions. The results showed that usability testing outcomes were independent of the method itself. With respect to physical environments, contextual factors were the most influential in the outcomes of usability testing. Although interruptions had the highest negative influence, the extent of this influence differed based on the type of interruption applied. In-person interruptions were the most disruptive because they influenced, not only the number of errors and task-load measurements, but also the time taken to perform tasks. Instant messaging increased the number of errors and the task load. Phone interruptions did not have noticeable effects on performance, but increased stress, time pressure and frustration. Based on our results, we concluded that if remote asynchronous usability testing is used, then the influence of contextual factors should be expected. Hence, these factors should be collected during testing because awareness of them is vital in improving data interpretation