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The development of a computer tool to be used by children with learning difficulties in spelling is described in this thesis. Children with spelling disabilities were observed by the author, and their errors were recorded. Based on analysis of these errors, a scheme of error classification was devised. It was hypothesized that there were regularities in the errors; that the classification scheme describing these errors could provide adequate information to enable a computer program to 'debug' the children's errors and to reconstruct the intended words; and that the children would be able to recognize correct spellings even if they could not produce them. Two computer programs, the EDITCOST and the PHONCODE programs, were developed. These incorporated information about the types of errors that were made by the children, described in terms of the classification scheme. They were used both to test the hypotheses and as potential components of a larger program to be used as a compensatory tool. The main conclusions drawn from this research are: The errors made by children with learning difficulties in spelling show regularities in both the phoneme-grapheme correspondences and at the level of the orthography. The classification scheme developed, based on the children's errors, provides a description of these errors. It provides adequate information to enable a computer program to 'debug' the children's errors and to reconstruct the intended words. Computer tools in the form of interactive spelling correctors are able to offer a correction for a substantial proportion of the child's errors, and could be extended to provide more information about the children's errors. They are also suitable for use with other groups of children.

Participatory Design (PD) is an approach for designing new technologies which involves end users in the design process. It is generally accepted that involving users in the design process gives them a sense of ownership over the final product which enhances its usability and acceptance by the target population. Employing a PD approach can introduce multiple challenges especially when working with autistic children. Many approaches for involving autistic children and children with special needs were developed to address these challenges. However, these frameworks introduce their own limitations as well. There is an ethical dilemma to consider in the involvement of autistic children in the design process. Although we established the ethical benefit of involving children, we did not address the ethical issues that will result from involving them in these research projects. Among other issues, the nature of design workshops we as a community currently run require working with unfamiliar researchers and communicating with them while social and communication differences are one of the main diagnostic criteria for autism. When designing for autistic children and other vulnerable populations an alternative (or most often an additional) approach is designing with proxies. Proxies for the child can be one of several groups of other stakeholders, such as: teachers, parents and siblings. Each of these groups may inform the design process, from their particular perspective, and as proxies for the target group of autistic children. Decisions need to be made about what stages in the design process are suited to their participation, and the role they play in each case. For this reason, we explore the role of teachers, parents, autistic adults and neurotypical children as proxies in the design process. To explore the roles of proxies we chose friendship between autistic and neurotypical children as the context we are designing for. We are interested in understanding the nature of children's friendships and the potential for technology to support them. Although children themselves are the ones who experience friendship and challenges around its development and peer interaction, they might find it difficult to articulate the challenges they face. Furthermore, it is unrealistic to expect children to identify strategies to help them overcome the challenges with friendship development that they are facing as it assumes children have the social skills to come up with these strategies in the first place. Hence, it is necessary in this context to consider proxies who can identify challenges and suggest ways to overcome them.

Pretend play is a key developmental tool, with its early performance being a predictor for later language, social interaction and communication skills. The level of these skills in turn influences an individual's ability to build social relationships, independence and integrate into the society. Autistic children, however, show marked impairments in the qualitative and quantitative use of pretend play compared to typically developing children. Hence, researchers recommend the development of pretend play as one of the main targets of educational programs for young autistic children. However, such educational programs are very rare and those that exist have moderately successful results, at best. Recently, technology is gaining popularity for its educational and therapeutic potential with autistic individuals. A new form of technology that allows physical objects to be augmented with digital information showed that children pretended more with the augmented objects compared to when the objects were not augmented. This raised the question of how can we design technology to facilitate pretend play in autistic children in the natural, school context, and whether it would help them transfer their learning to a non-technology setup. During this research, a series of studies with practitioners, children and researchers was carried out to understand how pretend play is supported in practice and how to produce a set of design guidelines for creating technologies to foster pretend play. Based on those studies, three digital, interactive stories were designed, where children could change physical objects into food or drinks. Then, to determine whether the application can help children develop pretend play, it was evaluated on a sample group of 9 children with autism, joined by a practitioner. Overall, this research revealed that the proposed application can help children develop pretend play. Children showed longer, more frequent and complex pretend play acts after playing with the interactive stories compared to before. Children responded positively to system's scaffolding: different types of pretend play acts with some of them being able to initiate (novel) symbolic play acts not specifically scaffolded by the system (or the adult) and diverse (unique) acts. Besides, children found the interactive play stories enjoyable with some of the practitioners asking for the tool to be used in the classroom.

Globally, miscarriage is affecting a substantial number of women: about 1 in 5 women who know they are pregnant miscarry. Importantly, miscarriage can be profoundly distressing, and lack of social support during and after a miscarriage can greatly affect women's wellbeing. Unfortunately, miscarriage is not a commonly discussed topic, despite the significant number of miscarriages occurring. As a result of the lack of discussion around the subject of miscarriage, it continues to be stigmatised and misunderstood. Consequently, there is inadequate communication between women who have experienced miscarriage and care networks when communicating their social support needs. This thesis investigates how technology can be meaningfully leveraged to enhance those communications. As a theoretical framework, the thesis author uses the Circles of Care Model, which has previously successfully been used to understand the complex context of caring for people with chronic illness. The research process was strongly participatory, inspired by principles of Community-Based Participatory Research. The main contributions of this thesis are: (a) an in-depth and rich holistic contextual understanding of the social support needs of women who have miscarried, describing in-depth their practices and use of technology (b) extending the Circles of Care Model approach to designing a socio-technical system for miscarriage care (c) proposing empirical design goals for socio-technical systems for miscarriage care that are grounded in mixed methods research with women from different cultures and different health care systems. In collaboration with ProHealth Lab, University of Indiana, Bloomington, United States, we began with an exploratory Asynchronous Remote Communities (ARC) study to investigate the breadth of miscarriage experiences, the support needs that arise, the people who can help, and the potential scope for technology to facilitate the support needed. The study involved 16 activities (discussions, creative tasks, and surveys) posted in two closed, secret Facebook groups over eight weeks. Women who have miscarried face barriers to receiving appropriate social support when communicating with their care network. Since miscarriage still carries a considerable stigma, women hear unwanted responses and belittlement of the loss, which made them more hesitant to reach out. They often felt unable to discuss their feelings and thoughts openly, as they feared a lack of empathy. Without having a guiding hand, women who have miscarried feel alone in this experience. They live experience that no one has prepared them to, very few people understand and sometimes is challenging to get support. This left many overwhelmed with complex social support needs while in a raw emotional state, and often with insufficient informational, emotional, esteem and network support at the time. While women experiencing a miscarriage utilise various technology channels for seeking support when other options fail them, each woman only focuses on a few online streams. We developed the Miscarriage Circle of Care Model (MCCM) to mapping the formal, informal care networks, and their respective roles in providing social support. Our findings highlight the importance of integrating the Peer Advisor support to provide holistic support for a woman experiencing a miscarriage. Next, the thesis author carried out five sets of 1:1 co-design workshops with women who have miscarried to investigate how technology might help address their unmet support needs, given the map of formal and informal care networks we developed. The workshops were structured around a journey mapping exercise. The thesis author also used card sorting to explore mental models of miscarriage support. The thesis author collected data both from women who had miscarried and those who had not experienced miscarriage themselves but felt a strong connection to the topic. We involve women who have not experience a miscarriage in the process to explore the different clustering behaviour between women with experience of miscarriage and those without experience, which in turn, help to understand how the experience of miscarriage changes the perception of support. The thesis author distilled the findings into actionable design goals, which were then instantiated in a wireframe prototype of the socio-technical system solution, which was designed to be able to fit into a pregnancy app. The thesis author evaluated the prototype in another five series of 1:1 workshops using techniques from usability testing, such as task analysis, and methods from service design, such as love letters / break up letters. Overall, women considered the prototype to be useful and acceptable, with suggestions for improvements. The thesis author concludes with a critical reflection of the process and findings and provides a conclusive description and suggestions for implementing them in practice. Through reflection on the experiences in conducting research for this thesis, including the difficulties we faced and decisions we made, we derive insights into the role of design, power relations in the community and research in a sensitive area. We conclude with a discussion of limitations and discuss how the MCCM developed in this thesis might be implemented within existing miscarriage care in the United States and United Kingdom healthcare systems.

Relative infrequency of communication initiation, particularly initiations that involve attention-sharing or other social purposes, appears to negatively impact the later-life outcomes of children with autism. Strategies to improve or encourage initiation skills in autism are hampered by the need for the behaviour to be spontaneous (i.e. unprompted by a partner). One potential approach that addresses the spontaneity issue is to extrinsically motivate initiations by changing aspects of the child’s environment such that they merit, or even demand, initiating a communication. Detecting subjectively inconsistent (i.e. discrepant) aspects in game-like virtual contexts appears to be something that inherently interests young children with autism, and can motivate them to initiate spontaneous, positive communications. Initial evidence for discrepancy as a communicative motivator came from a study which re-analysed video data from an existing autism and technology project (ECHOES), illustrating that a heterogeneous group of children all reacted frequently and socially to naturally occurring (i.e. unintentional, non-designed) discrepant aspects within ECHOES. A set of high-level design principles was developed in order to capture “lessons learned” from ECHOES that might facilitate re-creation of a similar pattern of spontaneous, positive initiation around discrepancy. A second, proof-of-concept study implemented these design principles in a set of three new touch-screen games (Andy’s Garden) that sought to establish, and then deliberately violate, child expectations (i.e. provide discrepancy-detection opportunities: DDOs). Children reacted socially and positively to the new games and DDOs. The results of this study allow us to answer its overall questions affirmatively: it is possible to motivate children’s communication–specifically, their initiation–by including deliberately-designed DDOs in a set of games. These findings are the first step towards determining whether discrepancy-detection opportunities may form a component of a future technology-based communication skills intervention, capable of changing children’s initiation behaviour outside of a game context.

Children with Autism Spectrum Conditions (ASC) have difficulties in learning social and communication skills. This leads to impairments in social interaction, including lack of understanding others’ intentions, emotions, and mental states, and impairments in communication both verbal and nonverbal. One of the most widely used interventions that addresses social and communication skills is the “social story”. A social story aims to support children with ASC in coping with their own behaviour. Practitioners use social stories to present specific scenarios and to help children understand how they should respond. However, the development of social stories is time consuming, and teachers comment that it is difficult to share them as a resource for others or to customise them to individual children, using their current tools. This thesis explores how a social story authoring tool can be designed, developed and evaluated. The final aim is to better support practitioners in writing, using and assessing social stories for children with ASC compared with their current approaches. A series of studies with practitioners and researchers was carried out to inform the design of a social story authoring tool and to evaluate it. A framework for social stories was built with the purpose of informing the design. Based on this framework, a prototype was iteratively designed and developed. The final prototype (ISISSImproving Social Interaction through Social Stories) was evaluated with practitioners with experience in social story interventions. The evaluation showed that ISISS is perceived by practitioners to be a considerable improvement over their current approaches. The methodology employed in this research combines Action Research, User-Centred Design and Participatory Design. Practitioners and researchers were empowered with different roles at different research stages in order to maximise their contributions to the development process.

This thesis applies concepts from Vladimir Propp’s model of the narrative structure of fairy tales (Propp’s morphology) to a story authoring tool for children. A computer story authoring application based on Propp’s morphology is developed and evaluated through empirical studies with children. Propp’s morphology is a promising model of narrative for a children’s story authoring tool, with the potential to give children a powerful mental model with which to construct stories. Recent research has argued for the use of computer-based interactive narrative authoring tools (which enable the construction of interactive narrative computer games in which the player can affect or change the plot) to support children’s narrative development, and a number of interactive narrative systems use Propp’s morphology as their underlying model of narrative. These interactive narrative tools have many potential learning benefits and a powerful motivational effect for children, who enjoy using them to create narrative games. The potential of an interactive narrative system based on Propp’s morphology to support children’s construction of narratives seems great, combining Propp’s rich narrative model with the motivational benefits of interactive narrative. Before the application of Propp’s morphology in an interactive narrative game creation tool to support children’s writing could be pursued, it was necessary to study children’s story writing with Propp’s morphology. How can Propp’s morphology be represented in a story authoring tool for children? Can children apply Propp’s abstract narrative concepts to the task of creating their own original stories? How does using Propp’s morphology affect the stories written by children? Using the Propp-based authoring tool that is presented in this thesis children were able to grasp Propp’s abstract concepts and apply them to their own story writing. The use of a story authoring tool based on Propp’s morphology improved some aspects of the narrative structure of the stories written by children, and children reported that they enjoyed using the tool and felt it was helpful to their story writing. This thesis lays the foundation and identifies the methods for further study of children’s appropriation of narrative structure by constructing stories using a story authoring tool based on Propp’s morphology.

Automatic story generation has a long-standing tradition in the field of Artificial Intelligence. The ability to create stories on demand holds great potential for entertainment and education. For example, modern computer games are becoming more immersive, containing multiple story lines and hundreds of characters. This has substantially increased the amount of work required to produce each game. However, by allowing the game to write its own story line, it can remain engaging to the player whilst shifting the burden of writing away from the game’s developers. In education, intelligent tutoring systems can potentially provide students with instant feedback and suggestions of how to write their own stories. Although several approaches have been introduced in the past (e.g., story grammars, story schema and autonomous agents), they all rely heavily on handwritten resources. Which places severe limitations on its scalability and usage. In this thesis we will motivate a new approach to story generation which takes its inspiration from recent research in Natural Language Generation. Whose result is an interactive data-driven system for the generation of children’s stories. One of the key features of this system is that it is end-to-end, realising the various components of the generation pipeline stochastically. Knowledge relating to the generation and planning of stories is leveraged automatically from corpora and reformulated into new stories to be presented to the user. We will also show that story generation can be viewed as a search task, operating over a large number of stories that can be generated from knowledge inherent in a corpus. Using trainable scoring functions, our system can search the story space using different document level criteria. In this thesis we focus on two of these, namely, coherence and interest. We will also present two major paradigms for generation through search, (a) generate and rank, and (b) genetic algorithms. We show the effects on perceived story interest, fluency and coherence that result from these approaches. In addition, we show how the explicit use of plots induced from the corpus can be used to guide the generation process, providing a heuristically motivated starting point for story search. We motivate extensions to the system and show that additional modules can be used to improve the quality of the generated stories and overall scalability. Finally we highlight the current strengths and limitations of our approach and discuss possible future approaches to this field of research.

Questions surrounding the impact of feedback in response to learner error are of interest in the fields of both Second Language Acquisition (SLA) and Intelligent Computer-Assisted Language Learning (ICALL). Current empirical SLA research seeks to ascertain what feedback types have a statistically significant positive impact on the process of acquiring a second language. Similarly, research in ICALL focuses on testing Intelligent Language Tutoring Systems (ILTSs) generally as well as the effectiveness of the feedback that they deliver. Despite this common interest in feedback, to date there has been no significant interdisciplinary research involving the two fields. The experiment reported here seeks to bridge this gap. Using a purpose-built ILTS, we tested the effect of two types of feedback on the acquisition of French past tense aspect among anglophone learners. Inspired by previous work in SLA, Explicit Inductive (EI) and Input Processing (IP) feedback were tested against a control group using a pre test/post test design. The learners completed a transformation and a grammaticality judgment task. For the transformation, they were presented with texts in the present tense and asked to re-write them in the past tense. For the grammaticality judgment, they had to rank the grammaticality of each sentence in a set of texts. In response to errors, EI feedback interpreted the aspectual meaning of the learners' answer and explicitly told them that it was not the most natural according to the context. In order to encourage formmeaning mapping, IP feedback asked the learners to match their erroneous answer to its interpretation. Two interpretations were presented: one was the target interpretation and the other matched the learner's answer. Having made their choice, they were then told whether it was correct as well as which interpretation was in fact target-like. The quantitative evaluation of the effectiveness of the EI and IP feedback was not statistically significant. We argued that this was due to a combined effect of learner level, target structure and feedback.

It has been suggested that theoretical computer science (TCS) suffers more than average from a lack of intrinsic motivation. The reasons provided in the literature include the difficulty of the subject, lack of relevance to the informatics degree or future careers, and lack of enjoyment of the learning experience. This thesis presents evidence of these claims derived from the results of an expert survey. Increasing the students’ perceived control of the learning experience has been shown to increase student motivation in numerous different settings. A few of those also showed increased student performance. This thesis proposes that game-building can be such a setting for the area of TCS. Within the area of TCS, the focus will be on the modelling skills (finite state automata, push-down automata, Turing machines, CCS, etc.) since they form the majority of the curriculum at undergraduate level. It will be demonstrated how arbitrary TCS modelling skills can be mapped onto a game-building framework and allow the students to learn about the former by using the latter. It is hypothesized that the success of the approach depends on the amount of control given to the student. To test this claim, two experimental conditions were used in a repeated-measures design: (1) own-game and (2) pre-defined game. In the former, students are asked to write a game of their own, whereas in the latter, they are asked to copy a pre-defined game. A large demand for the own-game context was observed and results of its effect on performance and enjoyment are presented. Although no main effect of the owngame condition versus the pre-defined game condition was found in terms of either enjoyment or performance, some interesting interaction effects between condition and motivational type were unveiled.

People with some types of motor disabilities who wish to generate text using a computer can find the process both fatiguing and time-consuming. These problems can be alleviated by reducing the quantity of keystrokes they must make, and one approach is to allow the user to enter shortened, abbreviated input, which is then re-expanded for them, by a program ‘filling in the gaps’. Word Prediction is one approach, but comes with drawbacks, one of which is the requirement that generally the user must type the first letters of their intended word, regardless of how unrepresentative they may consider those letters to be. Abbreviation Expansion allows the user to type reduced forms of many words in a way they feel represents them more effectively. This can be done by the omission of one or more letters, or the replacement of letter sequences with other, usually shorter, sequences. For instance, the word ‘hyphenate might be shortened to ‘yfn8’, by leaving out some letters and replacing the ‘ph’ and ‘ate’ with the shorter but phonetically similar ‘f’ and ‘8’. ‘Fixed Abbreviation Expansion’ requires the user to memorise a set of correspondences between abbreviations and the full words which they represent. While this enables useful keystroke savings to be made, these come alongside an increased cognitive load and potential for error. Where a word is encountered for which there is no preset abbreviation, or for which the user cannot remember one, keystroke savings may be lost. ‘Flexible Abbreviation Expansion’ allows the user to leave out whichever letters they feel to be ‘less differentiating' and jump straight ahead to type those they feel are most ‘salient’ and most characterise the word, choosing abbreviations ‘on the fly’. The need to memorise sets of correspondences is removed, as the user can be offered all candidates for which the abbreviation might be a representation, usually in small sets on screen. For useful savings to be made, the intended word must regularly be in the first or second set for quick selection, or the system might attempt to place the intended word at the very top of its list as frequently as possible. Thus it is important to generate and rank the candidates effectively, so that high probability words can be offered in a shortlist. Lower-ranking candidates can be offered in secondary lists which are not immediately displayed. This can reduce both the cognitive load and keystrokes needed for selection. The thesis addresses the task of reducing the number of keystrokes needed for text creation with a large, expressive vocabulary, using a new approach to flexible abbreviation expansion. To inform the solution, two empirical studies were run to gather letter-level statistics on the abbreviation methods of twenty-nine people, under different degrees of constriction (that is, different restrictions on the numbers of characters by which to reduce). These studies showed that with a small amount of priming, people would abbreviate in regular ways, both shared between users, and repeated through the data from an individual. Analysis showed the most common strategies to be vowel deletion, phonetic replacement, loss of double letters, and word truncation. Participants reduced the number of letters in their texts by between 25% (judged to maintain a high degree of comprehensibility) up to 40% (judged to be a maximum degree of brevity whilst still retaining comprehensibility). Informed by these results, an individual-word-level algorithm was developed. For each input abbreviation, a set of candidates is produced, ranked in such a way as to potentially save substantial keystrokes when used across a whole text. A variety of statistical and linguistic techniques, often also used in spelling checking and correction, are used to rank them so that the most probable will be easiest to select, and with fewest keystrokes. The algorithm works at the level of the individual word, without looking at surrounding context. Evaluation of the algorithm demonstrated that it outperforms its nearest comparable alternative, of ranking word lists exclusively by word frequency. The evaluation was performed on the data from the second empirical study, using vocabulary sizes of 2-, 10-, 20- and 30-thousand words. The results show the algorithm to be of potential benefit for use as a component of a flexible abbreviation expansion system. Even with the overhead of selection of the intended word, useful keystroke savings could still be attained. It is envisaged that such a system could be implemented on many platforms, including as part of an AAC (Augmentative and Alternative Communication) device, and an email system on a standard PC, thus making typed communication for the user group more comfortable and expansive.

This thesis addressed the production of media literacy practices in physical environments. It reflects a specific trajectory through a design space. The work is founded on four studies including design sessions and expositions in primary schools and in an art museum. The focus is on how to devise practices and make sense of media literacy tasks. the thesis addresses research problems of interaction design and media studies by:(a)configuring interactive tangibles and audiovisual media, to give different perspectives on media literacy within the same physical environment; (b) developing a set of practices which are attuned to how participants collaborate when accessing and producing media texts; (c) developing the design method by employing practical knowledge from theatre practices. The thesis tackles some specific design problems. One is that the qualities of the practices and qualities of the tools need to be addressed at the same time. Also, aesthetic and technical aspects often are indistinct. The thesis seeks help in some specific traditions in the performing arts. Some terms such as 'participatory theatre' and 'masked performance' are redefined in order to address both aspects of practices and tools. Terms such as 'gendre', 'framing', 'packaging', 'authoring', 'deconstruction', 'media agenda setting' are also redefined frm literature on media studies, through the production and study of collective activities. The thesis aims to contribute to the integration of findings in interaction desugb abd nedua stydues by (1) applying advances from interaction design for the support of new media literact practice in the physical environment; (2) applying the perspectives on media literacy which emerge from these integrations in order to contribute to current reesearch on interaction design. The thesis applies practices from the performing arts in order to enable a participatory design of physical environments for media literacy. The focus is on the role played by audience groups when they adopt media contents and artifacts.

This thesis considers possible criteria for the selection of example sentences for difficult or unknown words in reading texts for students of German as a Second Language (GSL). The examples are intended to be provided within the context of an Intelligent Computer-Aided Language Learning (ICALL) Vocabulary Learning System, where students can choose among several explanation options for difficult words. Some of these options (e.g. glosses) have received a good deal of attention in the ICALL/Second Language (L2) Acquisition literature; in contrast, literature on examples has been the near exclusive province of lexicographers. The selection of examples is explored from an educational, L2 teaching point of view: the thesis is intended as a first exploration of the question of what makes an example helpful to the L2 student from the perspective of L2 teachers. An important motivation for this work is that selecting examples from a dictionary or randomly from a corpus has several drawbacks: first, the number of available dictionary examples is limited; second, the examples fail to take into account the context in which the word was encountered; and third, the rationale and precise principles behind the selection of dictionary examples is usually less than clear. Central to this thesis is the hypothesis that a random selection of example sentences from a suitable corpus can be improved by a guided selection process that takes into account characteristics of helpful examples. This is investigated by an empirical study conducted with teachers of L2 German. The teacher data show that four dimensions are significant criteria amenable to analysis: (a) reduced syntactic complexity, (b) sentence similarity, provision of (c) significant co-occurrences and (d) semantically related words. Models based on these dimensions are developed using logistic regression analysis, and evaluated through two further empirical studies with teachers and students of L2 German. The results of the teacher evaluation are encouraging: for the teacher evaluation, they indicate that, for one of the models, the top-ranked selections perform on the same level as dictionary examples. In addition, the model provides a ranking of potential examples that roughly corresponds to that of experienced teachers of L2 German. The student evaluation confirms and notably improves on the teacher evaluation in that the best-performing model of the teacher evaluation significantly outperforms both random corpus selections and dictionary examples (when a penalty for missing entries is included).

The intention of most film editing is to create the impression of continuous action (“continuity”) by presenting discontinuous visual information. The techniques used to achieve this, the continuity editing rules, are well established yet there exists no understanding of their cognitive foundations. This thesis attempts to correct this oversight by proposing that “continuity” is actually what perceptual and developmental psychologists refer to as existence constancy (Michotte, 1955): “the experience that objects persist through space and time despite the fact that their presence in the visual field may be discontinuous” (Butterworth, 1991). The main conclusion of this thesis is that continuity editing ensures existence constancy by creating conditions under which a) the visual disruption created by the cut does not capture attention, b) existence constancy is assumed, and c) expectations associated with existence constancy are accommodated after the cut. Continuity editing rules are shown to identify natural periods of attention withdrawal that can be used to hide cuts. A reaction time study shows that one such period, a saccadic eye movement, occurs when an object is occluded by the screen edge. This occlusion has the potential to create existence constancy across the cut. After the cut, the object only has to appear when and where it is expected for it to be perceived as continuing to exist. This spatiotemporal information is stored in a visual index (Pylyshyn, 1989). Changes to the object’s features (stored in an object file; Kahneman, Treisman, & Gibbs, 1992), such as those caused by the cut, will go unnoticed. A duration estimation study shows that these spatiotemporal expectations distort due to the attention withdrawal. Continuity editing rules show evidence of accommodating these distortions to create perceived continuity from discontinuous visual information. The outcome of this thesis is a scientific understanding of filmic continuity. This permits filmmakers greater awareness of the perceptual consequences of their editing decisions. It also informs cognitive scientists of the potential of film as an analogue for real-world perception that exposes the assumptions, limitations, and constraints imposed upon our perception of reality.

Natural language is characterised by enormous linguistic variation (e.g., Fetzer (2003)). Such variation is not random, but is determined by a number of contextual factors. These factors encapsulate the socio-cultural conventions of a speech community and dictate the socially acceptable, i.e. polite, use of language. Producing polite language may not always be a trivial task. The ability to assess a situation with respect to a hearer’s social, cultural or emotional needs constitutes a crucial facet of a speaker’s social and linguistic competence. It is surprising then that it is also a facet which, to date, has received very little attention from researchers in the natural language generation community. Linguistic variation occurs in all linguistic sub-domains including the language of education (Person et al., 1995). Thanks to being relatively more constrained (and hence more predictable with respect to its intentional aspects than normal conversations), teachers’ language is taken in this thesis as a starting point for building a formal, computational model of language generation based on the theory of linguistic politeness. To date, the most formalised theory of linguistic politeness is that by Brown and Levinson (1987), in which face constitutes the central notion. With its two dimensions of Autonomy and Approval, face can be used to characterise different linguistic choices available to speakers in a systematic way. In this thesis, the basic idea of face is applied in the analysis of teachers’ corrective responses produced in real one-to-one and classroom dialogues, and it is redefined to suit the educational context. A computational model of selecting corrective responses is developed which demonstrates how the two dimensions of face can be derived from a situation and how they can be used to classify the many linguistic choices available to teachers. The model is fully implemented using a combination of naive Bayesian Networks and Case-Based Reasoning techniques. The evaluation of the model confirms the validity of the model, by demonstrating that politeness-based natural language generation in the context of teachers’ corrective responses can be used to model linguistic variation and that the resulting language is not singnificantly different from that produced by a human in identical situations.

The use of Artificial Intelligence techniques in the development of educational software brought the hope of developing systems that would become personalised to each student and thus be of more benefit to him or her. But despite their added complexity, these Intelligent systems (ITSs, ILEs, ICALLs, etc.) do not always succeed in engaging the student. While a lot of effort has been spent investigating how to accommodate an instructional interaction to the student's knowledge, almost no work has been done in trying to accommodate the instruction to the student's motivational state. This is surprising, given the immense impact that a student's motivation has in his or her learning. The little previous work dealing explicitly with motivation in tutoring systems has focused mainly on the strategies that an Intelligent Tutoring System (ITS) could use to motivate the student. In this dissertation we focus on the prior (but we believe, fundamental), task of detecting the student's motivational state, on which the mentioned strategies could be used. We argue that the available theories of motivation in education are not specific enough and are of limited usefulness in order to implement a motivation detection component in an ITS. Thus, we argue for the need of empirical studies that can help us elicit formalised motivation diagnosis knowledge. To this effect, we discuss a number of empirical studies we performed in order to inform the design of an ITS simulation that detects the motivational state of a student. The main aspects of the motivation diagnosis architecture presented in this dissertation are a motivation self-report component and a motivation diagnosis component based on human teachers' motivation diagnosis knowledge, elicited via one of the mentioned empirical studies. This architecture was implemented as an ITS simulation in order to help us evaluate these motivation diagnosis techniques. The evaluation showed that, although not perfect, the motivation diagnosis techniques introduced in this dissertation seem to offer a reasonable level of accuracy in detecting a student's motivational state, and although the approach presented is not the only possible one and many aspects of this work can still be improved, we believe that it offers a promising step towards tutoring systems that care!.

The educational benefits of involving learners as active players in the learner modelling process have been an important motivation for research on this form of learner modelling, henceforth referred to as participative learner modelling. Such benefits, conceived as the promotion of learners' reflection on and awareness of their own knowledge, have in most cases been asserted on the grounds of system design and supported only by anecdotal evidence. This dissertation explores the issue of whether participative learner modelling actually promotes learners' reflection and awareness. It does so by firstly interpreting 'reflection' and 'awareness' in light of "classical" theories of human cognitive architecture, skill acquisition and meta-cognition, in order to infer changes in learner abilities (and therefore behaviour) amenable to empirical corroboration. The occurrence of such changes is then tested for an implementation of a paradigmatic form of participative learner modelling: allowing learners to inspect and modify their learner models. The domain of application centres on the sensorimotor skill of controlling a pole on a cart and represents a novel type of domain for participative learner modelling. Special attention is paid to evaluating the method developed for constructing learner models and the form of presenting them to learners: the former is based on a method known as behavioural cloning for acquiring expert knowledge by means of machine learning; the latter deals with the modularity of the learner models and the modality and interactivity of their presentation. The outcome of this research suggests that participative learner modelling may increase the abilities of learners to report accurately their problem-solving knowledge and to carry out novel tasks in the same domain—the sort of behavioural changes expected from increased learners' awareness and reflection. More importantly perhaps, the research suggests a viable methodology for examining the educational benefits of participative learner modelling. It also exemplifies the difficulties that such endeavours will face.

The technology of knowledge-based systems undoubtedly offers potential for educational modelling, yet its practical impact on today's school classrooms is very limited. To an extent this is because the tools presently used in schools are EMYCIN -type expert system shells. The main argument of this thesis is that these shells make knowledge-based modelling unnecessarily difficult and that tools which exploit knowledge acquisition technologies empower learners to build better models. We describe how such tools can be designed. To evaluate their usability a model-building course was conducted in five secondary schools. During the course pupils built hundreds of models in a common range of domains. Some of the models were built with an EMYCIN -type shell whilst others were built with a variety of knowledge acquisition systems. The knowledge acquisition systems emerged as superior in important respects. We offer some explanations for these results and argue that although problems remain, such as in teacher education, design of classroom practice, and assessment of learning outcomes, it is clear that knowledge acquisition systems offer considerable potential to develop improved forms of educational knowledge-based modelling.

This thesis describes a formal model of a subtype of humour, and the implementation of that model in a program that generates jokes of that subtype. Although there is a great deal of literature on humour in general, very little formal work has been done on puns, and none has been implemented. All current linguistic theories of humour are over-general and not falsifiable. Our model, which is specific, formal, implemented and evaluated, makes a significant contribution to the field. Punning riddles are our chosen subtype of verbal humour, for several reasons. They are very common, they exhibit certain regular structures and mechanisms, and they have been studied previously by linguists. Our model is based on our extensive analysis of large numbers of punning riddles, taken from children's joke books. The implementation of the model, JAPE (Joke Analysis and Production Engine), generates punning riddles, from a humour independent lexicon. Pun generation requires much less world knowledge than pun comprehension, making it feasible for implementation. To support our claim that all of JAPE's output is punning riddles, we conducted an evaluatory experiment. We took JAPE texts, human-generated texts, nonsense non-jokes and sensible non-jokes, and asked joke experts to evaluate them. For joke experts, we used 8-11 year old children, since psychological research suggests that this age group enjoys, and can recognize, punning riddles better than other age groups. The results showed that JAPE's output texts are, in fact, recognizably jokes. The evaluation showed that our model adequately describes a significant subtype of verbal humour. We believe that this model can now be expanded to cover puns in general, as well as other types of linguistic humour.