Quality assessment of e-commerce websites using Bayesian belief networks

This thesis raises the issue of quality in E-commerce websites and addresses methodologies and approaches to standardize their assessment. The thesis blends the knowledge of academic research with the opinions and insights from experts and practitioners in the field to provide a comprehensive view of the issues and their remedies. The most experienced and successful E-commerce companies are beginning to realize that key determinants of success or failure are not merely a web presence or a low price but delivering a high quality website. Recent research shows that price and promotion are no longer the main draws for customers to make a decision on a purchase. More sophisticated online customers would rather pay a higher price to a provider with high quality service. Given that the establishment of an E-commerce website is mainly a software development effort; there are several standards that apply in governing the quality of such development. There seems to be an almost overwhelming abundance of quality standards that lead to a high level of cynicism and skepticism surrounding them and the eventual lack of use. Furthermore, no standard can directly predict the quality a website under development is going to achieve. Past approaches concerning the quality of E-commerce websites emphasize usability standards using techniques like feature inspection and collecting data about end-users' opinion by questionnaires. These methods provide important feedback and their results can be utilized as a useful background for future work, however, they do not contribute directly to a dynamic model that enables forecasting. The study of quality in the domain of the Internet in general, and E-commerce in particular, poses new challenges as technology evolves, including methods and metrics for estimating, managing quality during the product life cycle and quality-of-use measurement. The solution proposed by this research is to use a Bayesian Belief Network model. This model provides a consistent and practical approach to assessing the quality of the website. The assessment can be carried out before the completion of the website development, thus, providing insight on the trend and direction for correction and improvements. It can also be carried out on completed and operational work, providing analysis of areas for improvement. The model should be relatively quick and practical in providing an overall comprehensive assessment with root-cause analysis that would lead to corrective measures to improve the quality of the E-commerce website. In this research idioms were applied in realizing a complete Bayesian Belief Network model. The conclusions are measured against comparative assessment to validate the practical benefits of the work accomplished. The WebQual method was utilized to validate the "belief" established by the model.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Quality assessment of e-commerce websites using Bayesian belief networks

This thesis raises the issue of quality in E-commerce websites and addresses methodologies and approaches to standardize their assessment. The thesis blends the knowledge of academic research with the opinions and insights from experts and practitioners in the field to provide a comprehensive view of the issues and their remedies. The most experienced and successful E-commerce companies are beginning to realize that key determinants of success or failure are not merely a web presence or a low price but delivering a high quality website. Recent research shows that price and promotion are no longer the main draws for customers to make a decision on a purchase. More sophisticated online customers would rather pay a higher price to a provider with high quality service. Given that the establishment of an E-commerce website is mainly a software development effort; there are several standards that apply in governing the quality of such development. There seems to be an almost overwhelming abundance of quality standards that lead to a high level of cynicism and skepticism surrounding them and the eventual lack of use. Furthermore, no standard can directly predict the quality a website under development is going to achieve. Past approaches concerning the quality of E-commerce websites emphasize usability standards using techniques like feature inspection and collecting data about end-users' opinion by questionnaires. These methods provide important feedback and their results can be utilized as a useful background for future work, however, they do not contribute directly to a dynamic model that enables forecasting. The study of quality in the domain of the Internet in general, and E-commerce in particular, poses new challenges as technology evolves, including methods and metrics for estimating, managing quality during the product life cycle and quality-of-use measurement. The solution proposed by this research is to use a Bayesian Belief Network model. This model provides a consistent and practical approach to assessing the quality of the website. The assessment can be carried out before the completion of the website development, thus, providing insight on the trend and direction for correction and improvements. It can also be carried out on completed and operational work, providing analysis of areas for improvement. The model should be relatively quick and practical in providing an overall comprehensive assessment with root-cause analysis that would lead to corrective measures to improve the quality of the E-commerce website. In this research idioms were applied in realizing a complete Bayesian Belief Network model. The conclusions are measured against comparative assessment to validate the practical benefits of the work accomplished. The WebQual method was utilized to validate the "belief" established by the model.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Reconocimiento de gestos basado en acelerómetros

En los últimos años, ha crecido de forma significativa el interés por la utilización de dispositivos capaces de reconocer gestos humanos. En este trabajo, se pretenden reconocer gestos manuales colocando sensores en la mano de una persona. El reconocimiento de gestos manuales puede ser implementado para diversos usos y bajo diversas plataformas: juegos (Wii), control de brazos robóticos, etc. Como primer paso, se realizará un estudio de las actuales técnicas de reconocimiento de gestos que utilizan acelerómetros como sensor de medida. En un segundo paso, se estudiará como los acelerómetros pueden utilizarse para intentar reconocer los gestos que puedan realizar una persona (mover el brazo hacia un lado, girar la mano, dibujar un cuadrado, etc.) y los problemas que de su utilización puedan derivarse. Se ha utilizado una IMU (Inertial Measurement Unit) como sensor de medida. Está compuesta por tres acelerómetros y tres giróscopos (MTi-300 de Xsens). Con las medidas que proporcionan estos sensores se realiza el cálculo de la posición y orientación de la mano, representando esta última en función de los ángulos de Euler. Un aspecto importante a destacar será el efecto de la gravedad en las medidas de las aceleraciones. A través de diversos cálculos y mediante la ayuda de los giróscopos se podrá corregir dicho efecto. Por último, se desarrollará un sistema que identifique la posición y orientación de la mano como gestos reconocidos utilizando lógica difusa. Tanto para la adquisición de las muestras, como para los cálculos de posicionamiento, se ha desarrollado un código con el programa Matlab. También, con este mismo software, se ha implementado un sistema de lógica difusa con la que se realizará el reconocimiento de los gestos, utilizando la herramienta FIS Editor. Las pruebas realizadas han consistido en la ejecución de nueve gestos por diferentes personas teniendo una tasa de reconocimiento comprendida entre el 90 % y 100 % dependiendo del gesto a identificar. ABSTRACT In recent years, it has grown significantly interest in the use of devices capable of recognizing human gestures. In this work, we aim to recognize hand gestures placing sensors on the hand of a person. The recognition of hand gestures can be implemented for different applications on different platforms: games (Wii), control of robotic arms ... As a first step, a study of current gesture recognition techniques that use accelerometers and sensor measurement is performed. In a second step, we study how accelerometers can be used to try to recognize the gestures that can make a person (moving the arm to the side, rotate the hand, draw a square, etc...) And the problems of its use can be derived. We used an IMU (Inertial Measurement Unit) as a measuring sensor. It comprises three accelerometers and three gyroscopes (Xsens MTI-300). The measures provided by these sensors to calculate the position and orientation of the hand are made, with the latter depending on the Euler angles. An important aspect to note is the effect of gravity on the measurements of the accelerations. Through various calculations and with the help of the gyroscopes can correct this effect. Finally, a system that identifies the position and orientation of the hand as recognized gestures developed using fuzzy logic. Both the acquisition of samples to calculate position, a code was developed with Matlab program. Also, with the same software, has implemented a fuzzy logic system to be held with the recognition of gestures using the FIS Editor. Tests have involved the execution of nine gestures by different people having a recognition rate between 90% and 100% depending on the gesture to identify

An investigation into alternative human-computer interaction in relation to ergonomics for gesture interface design

Recent, innovative developments in the field of gesture interfaces as input techniques have the potential to provide a basic, lower-cost, point-and-click function for graphic user interfaces (GUIs). Since these gesture interfaces are not yet widely used, indeed no tilt-based gesture interface is currently on the market, there is neither an international standard for the testing procedure nor a guideline for their ergonomic design and development. Hence, the research area demands more design case studies on a practical basis. The purpose of the research is to investigate the design factors of gesture interfaces for the point-andclick task in the desktop computer environment. The key function of gesture interfaces is to transfer the specific body movement into the cursor movement on the two-dimensional graphical user interface(2D GUI) on a real-time basis, based in particular on the arm movement. The initial literature review identified limitations related to the cursor movement behaviour with gesture interfaces. Since the cursor movement is the machine output of the gesture interfaces that need to be designed, a new accuracy measure based on the calculation of the cursor movement distance and an associated model was then proposed in order to validate the continuous cursor movement. Furthermore, a design guideline with detailed design requirements and specifications for the tilt-based gesture interfaces was suggested. In order to collect the human performance data and the cursor movement distance, a graphical measurement platform was designed and validated with the ordinary mouse. Since there are typically two types of gesture interface, i.e. the sweep-based and the tilt-based, and no commercial tilt-based gesture interface has yet been developed, a commercial sweep-based gesture interface, namely the P5 Glove, was studied and the causes and effects of the discrete cursor movement on the usability was investigated. According to the proposed design guideline, two versions of the tilt-based gesture 3 interface were designed and validated based on an iterative design process. Most of the phenomena and results from the trials undertaken, which are inter-related, were analyzed and discussed. The research has contributed new knowledge through design improvement of tilt-based gesture interfaces and the improvement of the discrete cursor movement by elimination of the manual error compensation. This research reveals that there is a relation between the cursor movement behaviour and the adjusted R 2 for the prediction of the movement time across models expanded from Fitts’ Law. In such a situation, the actual working area and the joint ranges are lengthy and appreciably different from those that had been planned. Further studies are suggested. The research was associated with the University Alliance Scheme technically supported by Freescale Semiconductor Co., U.S

The creation of a binaural spatialization tool

The main focus of the research presented within this thesis is, as the title suggests, binaural spatialization. Binaural technology and, especially, the binaural recording technique are not particu-larly recent. Nevertheless, the interest in this technology has lately become substantial due to the increase in the calculation power of personal computers, which started to allow the complete and accurate real-time simulation of three-dimensional sound-fields over headphones. The goals of this body of research have been determined in order to provide elements of novelty and of contribution to the state of the art in the field of binaural spatialization. A brief summary of these is found in the following list: • The development and implementation of a binaural spatialization technique with Distance Simulation, based on the individual simulation of the distance cues and Binaural Reverb, in turn based on the weighted mix between the signals convolved with the different HRIR and BRIR sets; • The development and implementation of a characterization process for modifying a BRIR set in order to simulate different environments with different characteristics in terms of frequency response and reverb time; • The creation of a real-time and offline binaural spatialization application, imple-menting the techniques cited in the previous points, and including a set of multichannel(and Ambisonics)-to-binaural conversion tools. • The performance of a perceptual evaluation stage to verify the effectiveness, realism, and quality of the techniques developed, and • The application and use of the developed tools within both scientific and artistic “case studies”. In the following chapters, sections, and subsections, the research performed between January 2006 and March 2010 will be described, outlining the different stages before, during, and after the development of the software platform, analysing the results of the perceptual evaluations and drawing conclusions that could, in the future, be considered the starting point for new and innovative research projects

Proceedings of the 7th Sound and Music Computing Conference

Proceedings of the SMC2010 - 7th Sound and Music Computing Conference, July 21st - July 24th 2010