Effects of target expansion on selection performance in older computer users

Point and click interactions using a mouse are an integral part of computer use for current desktop systems. Compared with younger users though, older adults experience greater difficulties performing cursor positioning tasks, and this can present limitations to using a computer easily and effectively. Target expansion is a technique for improving pointing performance, where the target dynamically grows as the cursor approaches. This has the advantage that targets conserve screen real estate in their unexpanded state, yet can still provide the benefits of a larger area to click on. This paper presents two studies of target expansion with older and younger participants, involving multidirectional point-select tasks with a computer mouse. Study 1 compares static versus expanding targets, and Study 2 compares static targets with three alternative techniques for expansion. Results show that expansion can improve times by up to 14%, and reduce error rates by up to 50%. Additionally, expanding targets are beneficial even when the expansion happens late in the movement, i.e. after the cursor has reached the expanded target area or even after it has reached the original target area. Participants’ subjective feedback on the target expansion are generally favorable, and this lends further support for the technique

Expanding the bounds of seated virtual workspaces

Mixed Reality (MR), Augmented Reality (AR) and Virtual Reality (VR) headsets can improve upon existing physical multi-display environments by rendering large, ergonomic virtual display spaces whenever and wherever they are needed. However, given the physical and ergonomic limitations of neck movement, users may need assistance to view these display spaces comfortably. Through two studies, we developed new ways of minimising the physical effort and discomfort of viewing such display spaces. We first explored how the mapping between gaze angle and display position could be manipulated, helping users view wider display spaces than currently possible within an acceptable and comfortable range of neck movement. We then compared our implicit control of display position based on head orientation against explicit user control, finding significant benefits in terms of user preference, workload and comfort for implicit control. Our novel techniques create new opportunities for productive work by leveraging MR headsets to create interactive wide virtual workspaces with improved comfort and usability. These workspaces are flexible and can be used on-the-go, e.g., to improve remote working or make better use of commuter journeys

Practical, appropriate, empirically-validated guidelines for designing educational games

There has recently been a great deal of interest in the potential of computer games to function as innovative educational tools. However, there is very little evidence of games fulfilling that potential. Indeed, the process of merging the disparate goals of education and games design appears problematic, and there are currently no practical guidelines for how to do so in a coherent manner. In this paper, we describe the successful, empirically validated teaching methods developed by behavioural psychologists and point out how they are uniquely suited to take advantage of the benefits that games offer to education. We conclude by proposing some practical steps for designing educational games, based on the techniques of Applied Behaviour Analysis. It is intended that this paper can both focus educational games designers on the features of games that are genuinely useful for education, and also introduce a successful form of teaching that this audience may not yet be familiar with

Adolescent Reading Improvement: A Phenomenology of High School Students’ Perspectives

The purpose of this phenomenological study was to explore the experience of improvement in reading comprehension of adolescent readers who have made gains greater than what might be predicted based on previous growth in reading comprehension measures. These research questions guided this study: What influences have impacted the lived experiences of these improving readers? What barriers to reading improvement existed for these students? In addition, what school-related reading experiences, if any, hold meaning for these readers? What characteristics are shared among adolescent readers who have experienced better-than-expected growth? Interviews, story chart artifacts created by participants, and observations of students’ process and self-talk while reading short passages were collected from 12 students at Placid High School (pseudonym). Analysis was conducted using Hycner’s framework and hermeneutic analysis in order to discover the essence of these students’ experiences as improving readers. Methodologically, this study ascertained shared characteristics and experiences that influenced the reading comprehension growth of these adolescents through inductive study of all data. Four themes emerged through the data analysis: Reading as Provocation, Reading as Displacement, Reading as Relationship, and Reading as Confluence

Cursor relocation techniques to help older adults find 'lost' cursors

Older adult computer users often lose track of the mouse cursor and so resort to methods such as mouse shaking or searching the screen to find the cursor again. Hence, this paper describes how a standard optical mouse was modified to include a touch sensor, activated by releasing and touching the mouse, which automatically centers the mouse cursor to the screen, potentially making it easier to find a 'lost' cursor. Six older adult computer users and six younger computer users were asked to compare the touch sensitive mouse with cursor centering with two alternative techniques for locating the mouse cursor: manually shaking the mouse and using the Windows sonar facility. The time taken to click on a target following a distractor task was recorded, and results show that centering the mouse was the fastest to use, with a 35% improvement over shaking the mouse. Five out of six older participants ranked the touch sensitive mouse with cursor centering as the easiest to use

Investigation of head repositioning accuracy as a measure of cervicocephalic kinaesthetic sensibility in patients with chronic neck pain

The majority of people can expect to experience neck pain in their lifetime and some will go on to develop prolonged or repetitive episodes of neck pain or related symptoms. These persistent complaints have become a major cause of disability around the world. Although chronic ‘mechanical’ neck pain can be defined in clinical terms, the underlying pathology remains unclear. Research has failed to demonstrate a consistent relationship between the presence of neck pain and pathology such as degenerative changes. As such, there has been an increasing interest in altered neuro-muscular-articular function in the pathogenesis of neck pain. Over the last 17 years, the role of cervical proprioceptive (mechanoreceptive) dysfunction in the perpetuation of chronic neck pain has received increasing attention from researchers and clinicians. This is commonly referred to as cervicocephalic kinaesthetic sensibility (KS). Cervicocephalic KS has generally been studied utilising head repositioning accuracy (HRA) tasks. At the beginning of this study only seven reports had been published in the area. Following review of this literature, several focused areas of interest were apparent for further study - 1) comparison of KS in various patient subgroups (e.g., insidious onset vs ‘whiplash’); 2) development of more sophisticated methods of measuring head movement and repositioning errors; 3) establishing the characteristics of the tests such as method agreement and reliability; 4) comparison of the discriminative value of repositioning tasks to both subjective ‘straight ahead’ (SSA) and to non-neutral set points within the cervical range of motion (non-straight ahead or nSA). Investigation 1 used a laser pointer method to study head repositioning errors in patients with chronic neck pain of insidious onset. The results suggested that these patients with chronic neck pain show little evidence of impaired cervicocephalic KS, when measured as HRA-SSA. The study also served to highlight several difficulties with the laser pointer method of measurement and the relatively poor knowledge of HRA in healthy subjects. Most previous studies used the mean of 10 repetitions for the measurement but more recent studies utilised fewer repetitions. Although the laser pointer method is simple, inexpensive and easy to use, the method involves a degree of experimenter bias and inaccuracy. It also does not lend itself to concurrent evaluation of variables such as range of motion and speed of head movement. Investigations 2 & 3 focused on the development of the testing method and the introduction of the Zebris CMS 70P ultrasound system for the recording of HRA-SSA, namely; method agreement between a 5 and 10 repetition measuring protocol; method agreement between the laser pointer and Zebris system; the intra/inter-examiner reliability of measurement methods. The Zebris system results suggested that the two methods of measurement agree sufficiently well for the 5 repetition method to replace the 10 repetition method to obtain a mean HRA score and that both could be used interchangeably. Further results suggested that the Zebris and laser pointer methods do not agree sufficiently well to be used interchangeably. The test-retest reliability was comparable between both methods suggesting that from this perspective, either could be used for measuring HRA-SSA. The inter-rater test-retest reliability was comparable to the test-retest reliability suggesting that trained examiners could be interchanged when carrying out repeated measurements. Investigation 4, the final study in this thesis, investigated HRA with the Zebris system using the 5 repetition protocol in two groups of chronic neck pain patients; insidious onset and neck pain from a ‘whiplash’ injury. The results suggested that patients with chronic neck pain of both insidious onset and from a ‘whiplash’ injury show little evidence of impaired cervicocephalic KS when measured using HRASSA and nSA tests. These results conflict with previous studies Despite numerous investigations over the last 17 years, a test that can be routinely applied in the clinical setting for the purposes of diagnosis and treatment monitoring has not been established. Studies to date suggest that an active HRA test to SSA/NHP that is established by the patient may have the greatest discriminative value. Although HRA testing shows some promise in identifying deficits in ‘whiplash’ patients, it is unlikely that the KS tests identify specific subgroups of chronic neck pain patients. There have been several contradictory studies which have shown considerable overlap between patient and healthy groups. It is also unlikely that HRA tests represent a unique test of cervical proprioceptive function (peripheral or central integration) and therefore provide a test exclusive to neck disorders

An evaluation of computer-based radiographic methods in estimating dental caries and periodontal diseases

Reductions in dental diseases have resulted in a need for more accurate diagnostic and monitoring methods. The purpose of this study was to 1) identify the best diagnostic technique, 2) investigate the main factors which limit its validity and reliabilty and 3) devise methods to improve its reliability and 4) investigate ways of automating its use for general dental practice. From the literature review radiography was identified as the best current method with regard to validity, reliability, production of stable objective data and ease of use. However, irradiation geometry variations between serial films and subjective measurement errors were its principle limitations. Although an accurate semi-automatic caries measuring system exists, it is unsuitable for general practice due to lengthy operator interaction. A series of computer-based experiments were devised to evaluate further the digital subtraction radiography technique (DSR); develop a new method using stored regions of interest (ROI) to reduce subjective measurement errors; investigate the feasibility of completely automatic image analysis. In addition, an in vitro caries experiment was designed to demonstrate the effects of irradiation geometry variation on lesion size and caries scores. The results demonstrated that small variations in irradiation geometry can change radiographic scores. Misalignment of subsequent films beneath a video camera can cause significant errors in the DSR technique. The stored ROI method reduced cement-enamel junction to alveolar crest measurement errors to standard deviation 0.15mm. A fully automatic method for recognising teeth and bone crests was demonstrated. It was concluded that 1) radiography is currently the technique of choice, 2) a new significant methodological error for DSR has been demonstrated, 3) the subjective ROI method produced lower intra- and inter-examiner measurement errors compared to similar methods, 4) routine use of automatic methods may be feasible and should be investigated further and 5) standardised irradiation geometry is essential

Older People and Digital Technology From digital learners to digital leaders through participatory design with community-based organisations

PhDIt is predicted that there will be more people over the age of 65 than under 5 by 2050 in developed countries. In recognition of the needs of an ageing population, there is a growing field of research in HCI focused on engaging older people with digital technologies. This thesis contributes to the field of ageing in HCI through a community-based participatory design investigation into the challenges and opportunities for older people to engage with digital tools in their everyday lives. We demonstrate how the commitments, practices and values of participatory design can be used to better understand and foster engagement between digital tools and older people through the support of community-based organisations. This is achieved through two case studies. The rst study with a traditional computer class at a local day centre. The second with a London-based intergenerational running club. The research reflects on and examines the details and decisions of the learning and adoption process across these two studies. We expand our view beyond the digital tools to the influences and situations that contribute to older people's attitudes and usage. Through the lens of participatory design and communities of practice we discuss the considerations of values, problem-solving, and identity that can potentially be transferred to other non-traditional digital learning environments for older people. We provide recommendations and reflect on our challenges to serve as guidance for other researchers engaging in similar participatory work `in-the-wild'