Digital tabletop computers are an ideal platform for games with the social advantages of traditional tabletop games, such as board games and card games, combined with the more streamlined and automated gameplay of video games. Implementing a board game digitally allows for aspects of the game, such as routine in-game activities, rule enforcement and game progression, to be automated. However, the effect of this automation on the players’ social experience and enjoyment is poorly understood. To explore this question, a mixed-method study was carried out in which 24 groups of participants played either the abstract strategy board game Checkers or the cooperative board game Pandemic using three different interfaces: the original physical game; a digital tabletop interface which provided minimal automation in an attempt to replicate play of the original game; and a digital tabletop interface which automated many in-game activities, enforced the rules and managed the progression of the game. The study revealed that while automation does have the potential to reduce the overhead to play the game, it can lead to player frustration in several ways. Automating routine in-game activities and game progression can lead to severe awareness deficits. Automation of rule enforcement and management of the game state can streamline gameplay, but can lead to scenarios where players would prefer more control over the game. The negative space around the active game area is important to consider for storage of digital artifacts and physical objects above the table. Finally the digitization and automation of the games did not reduce social interaction, making digital tabletops a promising platform for social games. / Thesis (Master, Computing) -- Queen's University, 2012-01-08 10:32:08.405

This research details the development of a large-scale, computer vision-based touch screen capable of supporting a large number of simultaneous hand interactions. The system features a novel lightweight multi-point tracking algorithm to improve real-time responsiveness. This system was trialled for six months in an exhibition installation at World Expo 2005 in Aichi, Japan, providing a robust, fault-tolerant interface. A pilot study was then conducted to directly compare the system against other, more established input methods (a single-touch case, a two-mouse case and a physical prototype) to determine the effectiveness and affordances of the multi-touch technology for arranging information on a large-scale wall space in a paired collaborative task. To assist in this study, a separate visualisation and interaction classification tool was developed, allowing the replay of XML log data in real time to assist in the video analysis required for observation and hypothesis testing.

Multi-display environments (such as the pairing of a digital tabletop computer with a set of handheld tablet computers) can support collocated interaction in groups by providing individuals with private workspaces that can be used alongside shared interaction surfaces. However, such a configuration necessitates the inclusion of intuitive and seamless interactions to move digital objects between displays. While existing research has suggested numerous methods to bridge devices in this manner, these methods often require highly specialized equipment and are seldom examined using real-world tasks. This thesis investigates the use of two cross-device object transfer methods as adapted for use with commonly-available hardware and applied for use in a realistic task, a familiar tabletop card game. A digital tabletop and tablet implementation of the tabletop card game Dominion is developed to support each of the two cross-device object transfer methods (as well as two different turn-taking methods to support user identification). An observational user study is then performed to examine the effect of the transfer methods on groups’ behaviour, examining player preferences and the strategies which players applied to pursue their varied goals within the game. The study reveals that players’ choices and use of the methods is shaped greatly by the way in which each player personally defines the Dominion task, not simply by the objectives outlined in its rulebook. Design considerations for the design of cross-device object transfer methods and lessons-learned for system and experimental design as applied to the gaming domain are also offered.

Context. Smartphones contain advanced sensors called microelectromechanical systems(MEMS). By connecting a smartphone to a computer these sensors can be used to test new interaction techniques for games. Objective. This study aims to investigate an interaction technique implemented with a gyroscope that utilises the leaning of a user’s torso and compare it in terms of precision and enjoyment to using a joystick. Method. The custom interaction technique was implemented by using the gyroscope of a Samsung Galaxy s6 Edge and attaching it to to the torso of the user. The joystick technique was implementation by using the left joystick of an Xbox One controller. A user study was conducted and 19 people participated by playing a custom-made obstacle course game that tested the precision of the interaction techniques. After testing each technique participants took part in a survey consisting of questions regarding their enjoyment using the technique. Result. The results showed that the leaning technique was not as precise as the joystick implementation. The participants found the learning technique to be more fun to use and also more immersive compared to the joystick implementation. The leaning technique was however also more uncomfortable and difficult to use, and players felt less competent in their ability to control the player character with it. Conclusion. The performance difference might have been due to the lack of familiarity with the leaning technique compared to the joystick implementation. The leaning technique was more difficult to use and more uncomfortable than the joystick method. However, the leaning technique was also more fun to use and more immersive. This offers up the opportunity to keep exploring possibilities with this technique.

Bitcoin is a digital currency that is used by people all around the world. The goal of this paper is to give an idea about how much trust there is in bitcoin among its users. This paper has used an online survey aimed at bitcoinusers and a content analysis to collect data about this trust. The conclusions show that there seems to be some trust in bitcoin as a technology and this is based on that the users have a good understanding about how bitcoin works. They also share their knowledge about bitcoin to people around them. The trust between people in the bitcoin network on the contrary doesn’t seem as high because certain technological properties hurt this trust. The survey showed that only a small percentage of the users started to use bitcoin to buy and sell products, which may indicate a lower degree of trust in other people.

Due to limited hardware, effectively using the available resources is crucial for mobile games. Texture compression is a fundamental technique in game development to reduce the demand of memory and bandwidth usage. This thesis evaluates JPEG, PVRTC and uncompressed PVR with emphasis on loading time, memory footprint, application size and visual quality. The goal of this case study is to find the most suitable compression technique for a specific game. A variant of uncompressed PVR, RGBA4444, was found to be the best technique to use in this case. It was also concluded that JPEG compression in general is a bad choice for games due to the lack of an alpha channel. Severe visual artifacts were noticed on frame-by-frame animation when using PVRTC. It is therefore interesting to investigate other animation techniques, such as skeletal animation, in combination with texture compression, to avoid such artifacts.

User studies play a vital role in data visualization research because they help measure the strengths and weaknesses of different visualization techniques quantitatively. In addition, they provide insight into what makes one technique more effective than another; and they are used to validate research contributions in the field of information visualization. For example, a new algorithm, visual encoding, or interaction technique is not considered a contribution unless it has been validated to be better than the state of the art and its competing alternatives or has been validated to be useful to intended users. However, conducting user studies is challenging, time consuming, and expensive. User studies generally requires careful experimental designs, iterative refinement, recruitment of study participants, careful management of participants during the run of the studies, accurately collecting user responses, and expertise in statistical analysis of study results. There are several variables that are taken into consideration which can impact user study outcome if not carefully managed. Hence the process of conducting user studies successfully can take several weeks to months. In this dissertation, we investigated how to design an online framework that can reduce the overhead involved in conducting controlled user studies involving web-based visualizations. Our main goal in this research was to lower the overhead of evaluating data visualizations quantitatively through user studies. To this end, we leveraged current research opportunities to provide a framework design that reduces the overhead involved in designing and running controlled user studies of data visualizations. Specifically, we explored the design and implementation of an open-source framework and an online service (VisUnit) that allows visualization designers to easily configure user studies for their web-based data visualizations, deploy user studies online, collect user responses, and analyze incoming results automatically. This allows evaluations to be done more easily, cheaply, and frequently to rapidly test hypotheses about visualization designs. We evaluated the effectiveness of our framework (VisUnit) by showing that it can be used to replicate 84% of 101 controlled user studies published in IEEE Information Visualization conferences between 1995 and 2015. We evaluated the efficiency of VisUnit by showing that graduate students can use it to design sample user studies in less than an hour. Our contributions are two-fold: first, we contribute a flexible design and implementation that facilitates the creation of a wide range of user studies with limited effort; second, we provide an evaluation of our design that shows that it can be used to replicate a wide range of user studies, can be used to reduce the time evaluators spend on user studies, and can be used to support new research.

When watching interactive branched video, the viewer is given the opportunity to tailor the storyline of the video playback. This type of video puts the users in control of their viewing experiences and provides content creators with great flexibility how to personalize the viewing experience for individual viewers. When it comes to regular linear videos, the concept of having a playback bar visually presenting the playback is a well established implementation used for most (if not all) video players, but for interactive branched videos, that is not the case. Instead, most branched video implementations are typically custom-made on a per-video basis (e.g., see custom-made Netflix and BBC movies) and do not use a playback bar. With the goal to fill this void, a branched video player with a generalized playback bar that visualizes the tree-like video structure was developed in 2018 by students of the Information Technology program at Linköping University and will be made public with a publication in the near future. Within the preparatory work prior to making this branched video player public, this project included a three-phase user study, where we evaluated the playback bar and its implemented features and compared the video player with alternative designs. With this thesis, we highlight the value of a branched video playback bar and provide interesting insights into how it, and other design customization features, may best be integrated into a branched video player. Furthermore, we present an improved version of the video player in which the new implementations are based on, and motivated by, the results from the user study. Finally, we describe how further investigations may be done to evaluate the improved version of the video player.

Two-factor authentication (2FA) is a strong defense against account compromise. However, usability studies reveal challenges with 2FA setup. The process to manually setup and remove 2FA methods differs across websites. We present a system design for a 2FA manager to automatically setup and remove 2FA methods. Potential benefits are reduced time, fewer mistakes, consistent terminology, a single workflow for users to learn, and the ability to rapidly transition to a new 2FA method—e.g., when replacing a lost 2FA method. We create two proof-of-concept implementations of our design, one as a browser extension and one integrated as a feature in an existing password manager. We evaluated the browser extension implementation approach using a between-subjects user study (N=60). Our results show fewer mistakes and reduced time compared to manually adding and removing 2FA methods. Qualitative results show that users found the automated process easy to use and were enthusiastic about the 2FA manager's ability to help them rapidly replace 2FA methods in the case they lost their 2FA device.

Physical properties of objects are some of the features that are lost when users are immersed in today's virtual environments that usually only provide visual and auditory stimuli. In a quest to recover the physical perception of touch, in this work, we present two different studies to assess how force feedback applied solely on the wrist can convey weight. This localized approach is implemented with a wearable device, which is an advantage regarding mobility. Part of our motivation comes from balance tasks that involve interaction with objects, where there is a need to perceive their weight.We first propose an experiment to assess how we can use the force feedback on the wrist to alter the weight perception when manipulating physical props in VR.Then, we implement and evaluate two experiments in several days setting with a single participant, using only virtual representations of the objects. In the first experiment, we propose a task involving ordering objects, from the lightest to the heaviest. The second experiment also assesses weight perception, but at this time, asking the participants to compare only two objects grabbed at distinct points. In both procedures, the tasks are repeated hundreds of times to remove any bias that can come from memorizing the orders and combinations presented. From these studies, we found that the force stimuli localized on the wrist are sufficient to convey weight information. We also found that grabbing the objects at different points affects the perceived weight to a certain extent due to how the two motion axes of the wrist are placed. The behavior we observed in weight discrimination, and its limitations are equivalent to the ones found in previous studies performed using real weights.Besides these studies, an additional contribution of this work is an effective experimental design relying on a single participant in a long term setting.