User's web page aesthetics opinion: a matter of low-level image descriptors based on MPEG-7

Analyzing a user's first impression of a Web site is essential for interface designers, as it is tightly related to their overall opinion of a site. In fact, this early evaluation affects user navigation behavior. Perceived usability and user interest (e.g., revisiting and recommending the site) are parameters influenced by first opinions. Thus, predicting the latter when creating a Web site is vital to ensure users’ acceptance. In this regard, Web aesthetics is one of the most influential factors in this early perception. We propose the use of low-level image parameters for modeling Web aesthetics in an objective manner, which is an innovative research field. Our model, obtained by applying a stepwise multiple regression algorithm, infers a user's first impression by analyzing three different visual characteristics of Web site screenshots—texture, luminance, and color—which are directly derived from MPEG-7 descriptors. The results obtained over three wide Web site datasets (composed by 415, 42, and 6 Web sites, respectively) reveal a high correlation between low-level parameters and the users’ evaluation, thus allowing a more precise and objective prediction of users’ opinion than previous models that are based on other image characteristics with fewer predictors. Therefore, our model is meant to support a rapid assessment of Web sites in early stages of the design process to maximize the likelihood of the users’ final approval

Visual Targeted Advertisement System Based on User Profiling and Content Consumption for Mobile Broadcasting Television

Content personalisation is one of the main aims of the mobile media delivery business models, as a new way to improve the user’s experience. In broadcasting networks, the content is sent “one to many”, so a complete personalisation where the user may select any content is not possible. But using the mobile bidirectional return channel (e.g. UMTS connection) visual targeted advertising can be performed in a simple way: by off-line storing the advertisement for selectively replacing the normal broadcasted advertisement. In fact, these concepts provide powerful methods to increase the value of the service, mainly in mobile environments. In this article we present a novel intelligent content personalisation system for targeted advertising over mobile broadcasting networks and terminals, based on user profiling and clustering, as a new solution where the use of content personalisation represents the competitive advantage over traditional advertising

Desarrollo de un modelo multivariante para el análisis objetivo de la estética web

El aspecto visual de una interfaz gráfica no representa únicamente una cuestión de gusto. De hecho, su influencia es tal que tanto la experiencia de usuario como otros aspectos complementarios tales como la usabilidad, la satisfacción o fiabilidad percibida dependen en gran medida del nivel estético apreciado. Por esta razón es de vital importancia que esta dimensión sea analizada y evaluada adecuadamente, propiciando con ello la aparición de una importante línea de investigación en el campo de la interacción hombre máquina. De acuerdo a esta idea, la presente tesis tiene como objetivo proponer un modelo multivariante para el análisis objetivo de la estética de las interfaces web basado en la utilización de un conjunto de descriptores visuales definidos a tal efecto. Este modelo surge como respuesta a las carencias detectadas en el estado actual de los métodos existentes y se basa en la caracterización de las interfaces como imágenes de acuerdo al hecho de que la impresión inicial del usuario, según la cual formará su opinión, se obtiene en un intervalo muy corto de tiempo durante el cual sólo son considerados los atributos más básicos de la percepción relacionados con tres factores concretos como lo son la luminancia, la crominancia y las texturas detectadas. Aspectos más complejos relativos al propio contenido o su presentación dentro de la interfaz influirían en niveles posteriores y, por lo tanto, quedarían fuera del ámbito de esta tesis. La apropiada combinación de los descriptores definidos para la caracterización del aspecto visual de la interfaz de acuerdo a las respuestas dadas por un conjunto amplio de usuarios sobre una muestra representativa de los distintos tipos de interfaces web existentes ha permitido la obtención de un modelo final gracias al cual puede derivarse una evaluación cualitativa de la estética sin necesidad de hacer estudios con usuarios finales. Esto permite reducir tanto los costes asociados a este tipo de análisis como los tiempos asociados a las posibles modificaciones que sean necesarias para alcanzar una solución de aspecto visual óptimo. Además, y dadas las distintas definiciones existentes de la estética en el entorno analizado, el modelo ha sido ampliamente validado y los resultados obtenidos han permitido concluir que representa, tal y como se esperaba, una mejor respuesta frente al análisis de la estética expresiva, más centrada en aspectos estéticos generales de mayor influencia en la percepción temprana, que en la estética clásica, enfocada en el estudio de la complejidad o la distribución del contenido en la interfaz propios de un análisis más profundo y, por lo tanto, de mayor duración. De forma adicional, se ha comprobado la adaptación del modelo a distintas características básicas de los usuarios, pudiendo definirse con ello perfiles concretos para los que la presente solución aporta mejores resultados. En esta línea, y debido a la importancia que tienen en el entorno multimedia actual, se ha analizado la adecuación del modelo sobre un tipo concreto de interfaces de usuario como son los buscadores webs, ratificando los resultados obtenidos y permitiendo con ello una completa validación de las hipótesis iniciales señaladas. ABSTRACT Visual aesthetics of a graphical interface is not only considered a matter of taste. In fact, its influence is such that both the user experience as other complementary aspects such as usability, satisfaction or perceived reliability depend largely on the appreciated aesthetic level. For this reason, and given the importance of this dimension in human computer interaction, it is vital that it is adequately assessed and analyzed. According to this idea, this thesis aims to propose a multivariate model for web interface aesthetics analysis based on the use of a set of visual descriptors specifically defined for this purpose. This model is a response to the weaknesses identified in the current methods, and it is based on the characterization of interfaces as images, due to the fact that users’ first impressions, essentials for the final opinion, are obtained in a very short time during which there are considered only three most basic perception attributes, which are related to three specific factors such as luminance, chrominance and texture of the image. Other complex aspects related to the content and its presentation and organization in the interface have a main influence in later levels of the perception, and for this reason they fall outside the scope of this thesis. The final model has been finally obtained thanks to an appropriate combination of these descriptors according to the answers given by a broad set of users over a representative sample of different types of web interfaces, providing a quality assessment of aesthetics without defining specific experiments with final users. Furthermore, its application can reduces both the costs associated with this type of analysis as the time associated with any visual changes that are necessary in order to achieve an optimal visual aspect solution. Moreover, given the different existing definitions of aesthetics in the environment analyzed, the model has been extensively validated. The obtained results have concluded that the model represents, as expected, a better response to the analysis of expressive aesthetics, more focused on general aesthetic aspects of greater influence on early perception that classical aesthetics, in charge of the study of interface complexity or layout content distribution, which are related to a deeper perception and therefore longer lasting. Additionally, the model adaptation over different basic users’ characteristics has been also proven in the validation phase. In this way, the model presents better results with some different profiles which have been identified. In this line, and because of the importance in today's multimedia environment, the response of the model has been also validated over a particular type of user interfaces such as web browsers, confirming the previous results and enabling a complete validation of the initial hypotheses

Regionalplan Mittlerer Oberrhein vom 12. Dezember 1979: Aenderung vom 25. Maerz 1987

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