Quantifying epistemic actions in human-computer interaction

As digital systems move away from traditional desktop setups, new interaction paradigms are emerging that better integrate with users’ realworld surroundings, and better support users’ individual needs. While promising, these modern interaction paradigms also present new challenges, such as a lack of paradigm-specific tools to systematically evaluate and fully understand their use. This dissertation tackles this issue by framing empirical studies of three novel digital systems in embodied cognition – an exciting new perspective in cognitive science where the body and its interactions with the physical world take a central role in human cognition. This is achieved by first, focusing the design of all these systems on a contemporary interaction paradigm that emphasizes physical interaction on tangible interaction, a contemporary interaction paradigm; and second, by comprehensively studying user performance in these systems through a set of novel performance metrics grounded on epistemic actions, a relatively well established and studied construct in the literature on embodied cognition. The first system presented in this dissertation is an augmented Four-in-a-row board game. Three different versions of the game were developed, based on three different interaction paradigms (tangible, touch and mouse), and a repeated measures study involving 36 participants measured the occurrence of three simple epistemic actions across these three interfaces. The results highlight the relevance of epistemic actions in such a task and suggest that the different interaction paradigms afford instantiation of these actions in different ways. Additionally, the tangible version of the system supports the most rapid execution of these actions, providing novel quantitative insights into the real benefits of tangible systems. The second system presented in this dissertation is a tangible tabletop scheduling application. Two studies with single and paired users provide several insights into the impact of epistemic actions on the user experience when these are performed outside of a system’s sensing boundaries. These insights are clustered by the form, size and location of ideal interface areas for such offline epistemic actions to occur, as well as how can physical tokens be designed to better support them. Finally, and based on the results obtained to this point, the last study presented in this dissertation directly addresses the lack of empirical tools to formally evaluate tangible interaction. It presents a video-coding framework grounded on a systematic literature review of 78 papers, and evaluates its value as metric through a 60 participant study performed across three different research laboratories. The results highlight the usefulness and power of epistemic actions as a performance metric for tangible systems. In sum, through the use of such novel metrics in each of the three studies presented, this dissertation provides a better understanding of the real impact and benefits of designing and developing systems that feature tangible interaction.

Epistemic modality in Ghanaian Pidgin English

This study investigates the expression of epistemic modality in a corpus of Ghanaian Pidgin English (GhaPE). The epistemic expressions are manually identified and thereafter distinguished from each other in terms of grammatical status and their indication of different epistemic and evidential notions. 7 different elements are found, ranging from 1 pre-verbal marker, 1 adverb, 2 particles and 3 complement-taking predicates. The results indicate, in line with existing research, that to differentiate between usage properties of individual modal expressions it may be necessary to subdivide them in terms of not only epistemic but also evidential meanings. Moreover, a functional parallel between the GhaPE particle abi, the Swedish modal particle väl and the Spanish adverbs a lo mejor and igual is demonstrated, with respect to their simultaneous function of expressing epistemic probability and asking the hearer for confirmation. Finally, the results suggest, contrary to previous accounts, that the pre-verbal marker fit may indicate epistemic possibility without the addition of a preceding irrealis marker go. It is proposed that future researchers should make use of bigger corpora in order to arrive at a more ample conception of both individual modal categories and their interrelations.