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Loss of cognitive potential is one of the greatest impediments to human wellbeing and productivity. Our healthcare system does a poor job of managing cognitive development and cognitive decline because it measures cognitive status relatively infrequently and in the limited times when cognitive measures are taken, the instruments used tend to be blunt. In the panel that we presented at HCS 2021 we examined the potential for cognitive assessment games to provide more frequent cognitive assessment. We reported on the use of a cognitive assessment game to screen for delirium risk in emergency patients, and the development of a suite of assessment games that can assess executive functions and other cognitive abilities in both young and old. We conclude with a discussion of knowledge translation and implementation science strategies for incorporating game-based cognitive assessment into healthcare practice.

With the rapidly aging population and the rising number of people living with dementia (PLWD), there is an urgent need for programming and activities that can promote the health and wellbeing of PLWD. Due to staffing and budgetary constraints, there is considerable interest in using technology to support this effort. Serious games for dementia have become a very active research area. However, much of the work is being done without a strong theoretical basis. We incorporate a Montessori approach with highly tactile interactions. We have developed a person-centered design framework for serious games for dementia with initial design recommendations. This framework has the potential to facilitate future strategic design and development in the field of serious games for dementia.

In our aging societies, slowing and managing cognitive decline has become a significant challenge for older people, caregivers, andhealthcare providers. In the past decade, there has been an explosion in productsaimed at providing cognitive interventions for the elderly in response to the growing market need. In thispaper, we present a framework for thinking about cognitive interventions, and a product typology based onthe level of technology used and the amount of tangibility/physical interactivity that products have. Weshow how current products fit within the proposed product typology framework. We also note shortfallsthat exist in validating products in terms of their claimed cognitive interventions, and in regions of theproduct technology space that deal withproducts that have low technology and low physical interactivity.

The picture-word interference (PWI) paradigm has been used to investigate the time course of processes involved in word retrieval, but is challenging to implement online due to dependence on measurements of vocal reaction time. We performed a series of four experiments to examine picture-word interference and facilitation effects in a form of covert picture naming, with and without gamification. A target picture was accompanied by an audio word distractor that was either unrelated, phonologically-related, associatively-related, or categorically-related to the picture. Participants were instructed to judge whether the name of the target picture ended in the phoneme assigned to the block by pressing corresponding keys as quickly and accurately as possible. Experiments 1 and 2 successfully replicated categorical interference and phonological facilitation effects at different optimal stimulus-onset-asynchronies (SOAs) between words and pictures. Experiment 3 demonstrated that a key gamification feature (collecting coins) motivated faster speed at the expense of accuracy in the gamified vs. experimental format of the task. Experiment 4 adopted the optimal SOAs and verified that the gamification reveals expected interference and facilitation effects despite the speed-accuracy tradeoff. These studies confirmed that categorical interference occurs earlier than phonological facilitation, while both processes are independent from articulation and inherent to word retrieval itself. The covert PWI paradigm and its gamification have methodological value for neuroimaging studies in which articulatory artifacts obscure word retrieval processes, and may be developed into potential online word-finding assessments that can reveal word retrieval difficulties with greater sensitivity.

Major depressive disorder (MDD) causes many negative consequences including suicide and disability, and is one of the leading preventable causes of death in many countries. The Hamilton Rating Scale for Depression (HAM-D) used in this paper evaluates depression severity based on 17 symptoms of MDD (i.e., the HAM-D 17 , referred to below as the HAM-D). Studying the relationship amongst MDD symptoms not only provides insight into depressive symptoms but also helps identify subgroups of patients with depression. We employ causal discovery to discover the causal and correlational relationships among HAM-D symptoms. To the best of our knowledge, this is the first study to investigate HAM-D using causal discovery.

Models that predict satisfaction with a service over time need to consider the impact of emotions and remembered quality of experience in predicting overall attitudes towards a service. However, prior research on subjective quality of experience has typically focused on experiments conducted in a single session or over a short period of time. Thus, there is a gap between our understanding of instantaneous quality of experience and long-term judgments, such as overall satisfaction, and likelihood to recommend and likelihood to churn. The goal of the study reported here was to carry out a longitudinal study that would provide initial insights into how experiences of service quality over time are accumulated into memories that then drive longer term attitudes about the service. Our longitudinal study was carried out over a period of roughly 4 weeks with around 3 sessions per week. To facilitate the study, an online service was constructed that would let participants search through YouTube videos, and that added impairments (specified according to an overall experimental design) to the videos before they were played. Participants were asked to rate several measures, including Technical Quality, after each video was viewed. They were also asked to give overall impressions after each session of five videos had been viewed. The results were analyzed in terms of both sequencing effects within sessions. and memory effects that carried over between sessions.

After eliciting 129 potential task-gesture combinations for 23 Smart TV tasks with a Canadian sample (N = 22), we then conducted studies that collected participant preference scores on mid-air bare-hand gestures for TV control in both Canada (N = 747) and China (N = 300), and we analyzed the effect of characteristics of individual participants on gesture preference scores. The results showed that age and cultural differences are important in determining task-gesture preferences. While exploratory, the present results indicate a need for more research in this area and suggest that one of two possible strategies may need to be adopted in designing future gesture interactions: 1) develop customized task-gesture combinations for different cultures and different age groups; 2) develop a core set of task-gesture combination possibilities and let users choose which gesture they want to use for each task.

The rapid aging of developed societies is creating an increasing number of cases of dementia and other aging-related diseases. Physical exercise has been shown to be beneficial for retaining cognitive, as well as physical function. In this paper we describe a system that we have developed for motivating older people to exercise. We begin by demonstrating how activity declines with age using an analysis of survey data (from 2003–2015) reported by the U.S. Bureau of Labor and Statistics on American Time Use Usage. We use multiple discriminant analysis to characterize which activities tend to become more, or less frequent as people age. We then review previous exergame approaches for motivating physical activity. After this we discuss a pedaling system that is designed to motivate and facilitate physical activity in the elderly using a combination of competition, social interaction, and engaging video content. We conclude with a discussion of how to adapt exergaming innovations to the context of use.

Many age-specific mental health problems can be related to maladaptive cognitive strategies for engaging with and processing the external environment in relation to self-perception and ego identity. These are essentially attentional balance problems, reflected in maladjustments of the subjective sense of presence in the external world. We present a theoretical rationale for well-being design that takes account of developmental changes, including cognitive aging, sleep, and the sense of presence. For example, young children may suffer from attentional problems, where events in the immediate environment are overly distracting. We see this as an overactive presence mechanism, or hyperpresence. As people become older, more waking time is spent in reminiscence and daydreaming. Eventually, the ability to give timely attention to the environment, as needed to carry out intentions, may become lost in hyperabsence. We specify several practical strategies for designing interactive technologies to help alleviate cognitive and behavioral problems, by restoring a more balanced relation between individual and environment.

New technologies, such as serious games and ambient activities, are being developed to address problems of under-stimulation, anxiety, and agitation in millions of people living with dementia in long term care homes. Frequent interactions with instrumented versions of these technologies may not only be beneficial for long term care residents, but may also provide a valuable new set of multifaceted data related to the health status of residents over time. In this paper, we develop a model for health monitoring in healthcare environments and we report on two studies that show how medically relevant data can be collected from elderly residents and emergency department patients in an unobtrusive way. The first study shows how data related to cognitive abilities can be collected from elderly emergency department patients and the second study shows how detailed data on a range of factors can be collected from ambient activity units designed to provide engaging interactions for long term care residents. In summary, this paper proposes the use of new technologies to transform long term care from a data poor to a data rich environment, where the health status of long term care residents and elderly patients is more closely monitored.

Treatment of dementia has, until recently, largely been based on medical models that address the immediate biological needs, but often fail to meet the individualized needs of the person, including social and psychological needs. Recently, Montessori approaches have been used to validate the whole person and to provide engaging alternatives to the responsive behaviors that arise from unmet needs. In this population, sedentary lifestyle is a particularly severe problem, and there is an urgent need for more physical exercise. Given not only the known benefits of exercise, but also the difficulty of providing traditional methods of physiotherapy in the volume required, automated methods for motivating, and rewarding physical exercise are needed. The research reported in this paper focuses on the development of technologies for aging well through increased cognitive and physical activity among people with dementia. Our goal is to develop solutions for some of the issues faced by long-term care environments by creating engaging and rewarding activities that are available to people with dementia on a 24x7 basis. We have developed units called Centivizers (for “in-centivizing” behavior) that show promise in improving or maintaining physical and cognitive status in dementia by providing people with rewarding, and always-on, opportunities for engaging experiences that motivate physical exercise and cognitive activity.

Many people living with dementia are under-stimulated and socially isolated. While there has been an increase in activities and programming based on recreational therapy and music therapy, such programs can cover only a fraction of the day for people with dementia and are resource demanding to execute. The result is that many people with dementia, who are institutionalized, are staying most of the day either in their rooms, sitting in communal areas, or wandering the hallways. A related problem is that people with dementia often have difficulty with social interactions and may become anxious or aggressive around people they do not recognize, or in situations they do not understand. Resulting responsive behaviours (e.g., hitting, screaming) may lead to overmedication and poor quality of life. Ambient Activity Technology (AAT) is a wall-mounted interactive tool designed for people with dementia. The AAT unit is available in the environment for easy access, and have been designed to augment existing programming and activities by providing self-accessed, engaging and personalized interactions at any time (24-hours per day, 7 days/week). AATs have been designed to reduce distress, in residents and caregivers, by substituting responsive behaviours and purposelessness with active and meaningful activities, distractions, and appropriate interventions. This paper describes the motivation behind the design and development of the AAT. The paper ends with a description of our summative evaluation research, which is currently in progress at several long-term care facilities in Ontario, Canada.

In previous research, we developed a serious target acquisition game (with moles as targets) for assessing cognitive speed. Tong, Chignell, Tierney, and Lee demonstrated that performance on the game may be a useful screening tool for risk of delirium onset. In this study, we validate a version of the game where there are not only targets (moles) that should be hit but also distractors (butterflies, or moles with hats) that should not be hit. We hypothesized that performance on the game should be a measure of response inhibition ability, which has been implicated as a factor in many types of psychopathology. We carried out an experiment (with 30 healthy participants) to test whether the serious game does in fact measure response inhibition by comparing game performance with a standard response inhibition task (the Go/No-Go discrimination task). Our results show that, with the distractors, the game does in fact assess response inhibition ability. We discuss the implications of this work for assessing executive functions in the elderly, and for evaluating recovery in neuro-rehabilitation, and declining ability to perform activities of daily living.

Curved displays are believed to create a feeling of immersiveness similar to virtual reality. However systematic studies are needed to demonstrate that this is, in fact, true and under what conditions. In an experimental study 24 participants compared five different displays (concave, convex, hemisphere, sphere and a flat display) in terms of their immersiveness and perceptibility, and they also rated their overall preferences. Both immersiveness and perceptibility affected overall preference ratings. Participants gave higher preference ratings to the convex and concave displays, which were rated high in immersiveness and perceptibility, but gave lower preference ratings to the hemisphere/spherical display which had high ratings on immersiveness but low ratings on perceptibility. The study results imply that curved displays do indeed create a feeling of immersiveness. Concave and convex displays were rated highly favorably and should receive more attention for applications where visual experience and a feeling of immersiveness is particularly important.

Purpose: Although extensive research has been carried out on the determinants of mobile or wearable health care technology (mHealth), as well as on its acceptance by patients and other health care providers, very little research has been done on physiotherapists' perspectives on the use of mHealth in their current or future practice. The aims of this study were to (1) explore the attitudes of physiotherapists toward mHealth using a modified technology acceptance model questionnaire, (2) understand the applications and delivery paradigms that are most desirable, and (3) assess the content validity of the questionnaire. Method: The questionnaire was administered online. Participants (n=76) were recruited using snowball and convenience sampling. Data were analyzed using factor analysis and partial least-squares path modelling. Results: Results indicate that perceived usefulness and perceived ease of use were related to early adoptive behaviour among participants. We found no evidence that age, gender, experience, or practice setting influenced early adoptive behaviour. Participants demonstrated favourable attitudes toward mHealth tools in clinical practice. Conclusions: This article provides initial insights into factors that are likely to be significant determinants of adoption of mHealth among physiotherapists. Further work, including qualitative research, will help to identify personal and institutional factors that will improve the acceptance of mHealth.

Current cognitive testing methods in the elderly rely on clinical assessments, which are time consuming, costly, and require highly trained staff (Kueider, Parisi, Gross, & Rebok, 2012). We are developing a serious game with the goal of improving the ergonomics of cognition assessment. Instead of pencil and paper, or a computer, we are using touch-based tablets in order to provide a highly mobile and usable form of cognitive assessment. We are currently conducting usability studies on elderly adults in different healthcare environments to evaluate the technology. This paper presents work on customizing the game for use by elderly adults in a hospital emergency department (ED) and it will discuss some of the results obtained thus far, focusing on the usability of the game for this clinical population. In addition to usability results we will also report on the validity of the game in terms of how well it agrees with existing methods of cognitive assessment that are used in the ED.

We conducted an experiment with 16 participants to investigate the effect of cognitive distraction on performance of a 1-D tracking task that simulated gap control in driving. Participants operated the tracking task with a foot pedal while performing a secondary task (an auditorily presented N-back task) under eight conditions involving all possible (2x2x2) combinations of degree of secondary task difficulty (1-back vs. 2-back), pedal tracking difficulty (hard vs. easy amounts of lag) and presence vs. absence of visual occlusion. In conditions involving occlusion participants could press a button to get rid of the occlusion for a short period of time, i.e., they used Voluntary Interruption of Occlusion (VIO). Our results showed that use of VIO is associated with updating ability and that it trades off against pedal tracking performance. We also found evidence that cognitive distraction due to the impact of updating requirements in the secondary N-Back task affects performance on the primary, pedal tracking, task.

Memories of experience are influenced by a peak-end effect [13]. Memories are modified to emphasize the final portions of an experience, and the peak positive, or negative, portion of that experience. We examine peak-end effects on judged Technical Quality (TQ) of online video. In two studies, sequences of different types of video disruption were varied so as to manipulate the peak-end effect of the experiences. The first experiment demonstrated an end effect, plus a possible peak effect involving negative, but not positive, experience. The second study manipulated payment conditions so that some sessions were structured as requiring payment to watch the video. The second study also distinguished between a peak effect and a possible sequence effect. Evidence was again found for an end effect, with a secondary effect of sequence, but no evidence was found for a peak effect independent of sequencing.

Emotion is critical to how health-related information is perceived and acted upon. This paper shares empirical and methodological insights from an eHealth multimedia usability study involving participants with type 2 diabetes, using a typical sample size for usability studies: n=10. Skin conductance sensors and a slider were used to assess emotional responses toward videos on disease complications. The videos featuring peers elicited trends of stronger emotional responses compared to the other video formats, for both emotion measures. Clustering was used to investigate patterns in slider usage; participants clustered into types characterized as: ‘responsive’, ‘judging’, and ‘unresponsive’. We examined slider and arousal data to estimate immersion and found that half of participants who moved the slider minimally experienced skin conductance spikes, indicating high immersion. We discuss implications for understanding high-impact eHealth multimedia and for measuring immersion and emotions using small samples common in usability studies.

Measures of emotion should accurately characterize the nature of an emotional experience and determine whether that experience is universal or unique to a subgroup or culture. We investigated the value of assessing emotion through skin conductance (an easy-to-interpret physiological measure) and sliders (frequently used and direct measures of perceived emotion). This paper describes findings from two experiments. The first evaluated various slider configurations and found that measured emotions successfully characterized the emotional nature of short videos. The second experiment collected the slider and skin conductance measures of emotion while one sample of Japanese participants and another sample of Canadian participants viewed longer videos. The measures were sensitive enough to identify cultural differences consistent with existing literature and were also able to identify parts of the experience where members from different cultures reacted consistently, pinpointing content that provoked a universal experience. We offer a toolkit of data interpretation techniques to gain more insight into the implicit and explicit emotion data: analyses for expressiveness and agreement that can infer states such as engagement and fatigue. We summarize the aspects of our measurement approach and toolkit in a model: the ability to distinguish the emotional nature of stimuli, individuals, and affective interaction.

This chapter reviews relevant research on emotion, focusing on aspects of emotion that are most relevant to human factors design. The review begins with a discussion of basic emotion concepts, such as low-level positive and negative affect; emotion dimensions of arousal and valence; and prototypical emotions, such as anger, happiness, and fear. The interaction between emotion processing and cognitive processes, such as attention, perception, and decision making, is also discussed. After a review of the nature of emotion, the problem of measuring emotions is considered. Available techniques for emotion measurement are surveyed, and recommendations are made concerning which techniques should be used in different contexts and interactive settings. Novel measures are also introduced for assessing variability in emotional experience and for measuring emotional expressiveness. After laying the intellectual groundwork for understanding the nature of emotional interaction and its measurement, the chapter then shifts to exploring the implications of emotional processing for the design of interactive systems. Affective designs are reviewed in the following domains: consumer products, health care, and robots. The chapter concludes with presentation of an initial set of guidelines relating to the design of interactive systems that take into account emotional processing. The material presented in this chapter is highly relevant to human factors engineering because knowledge of emotional processing and how it affects the state of operators or users and their performance can lead to more usable, effective, efficient, and satisfying interaction.

Emotional reactions are increasingly recognized as an important part of experiences with technology, and there is a need for rigorous investigation into the collection of self-reported emotional data. We examine the capture of continuous, quantitative, affective self-reports as a complement to existing methods of evaluating human-system or product interaction. This experiment investigated 12 participants' use of a single slider (for valence, from very negative to very positive) and two sliders (for valence and arousal) in response to approximately 45 minutes of a nature video. Individual differences and physiological data (heart rate variability and skin conductance) were recorded. Emotion ratings were significantly related to skin conductance, which both differed significantly across chapters with different video content. We observed a learning effect, where participants' response times to probe questions decreased across blocks. Cognitive load appeared higher in the two-slider condition, with a possibly larger learning effect, and significantly longer dwell times, when compared to one slider. Arousal self-ratings were contradicted by skin conductance measures. We conclude with recommendations concerning the use of sliders for assessment of emotional user experience.

The rapid development of blogs as a social networking tool has greatly increased the number of people who are expressing themselves in text published online. As yet little is known about the social psychology of online interaction using recently developed Web 2.0 functionalities. To what extent do principles of social psychology carry over into the online domain and how can appropriate use of those principles assist in activities such as community building, e-commerce, marketing, and personalization of services? There would seem to be a large number of novel research questions that can be posed with respect to online interaction. One pertinent question concerns the extent to which compatibility of personality influences online interaction. We investigated this question in terms of hypotheses derived from the personality research literature, using a two-part experiment. In the first study, eight participants wrote blogs in two distinct genres (personal diaries and commentaries) and rated their own personalities. In the second study 12 different participants judged the personality of authors as implied in the blog texts created in the first study. Those participants also completed a personality questionnaire and rated their attraction to the blog text author. Readers of the blog corpus were able to consistently judge the personality of the writers based solely on the text that they wrote. Moreover, they followed a well-established social rule regarding interpersonal attraction in real-life interaction. Blog readers were significantly more attracted to blog writers with more similar personalities-offering support that in a blog environment, ''birds of a feather flock together.'' Emotion word use in the blog corpus correlated with writer's personality, suggesting that online personality may be signalled by linguistic cues. The two most popular genres of blog writing, personal journal and commentary, differed in how accurately readers judged author personality traits. Based on the results obtained it is suggested that personality is an important determinant and that further research on how people communicate with blogs will be relevant to social network analysis and to marketing.

This paper describes a study of content and communication processes in multidisciplinary meetings of healthcare professionals, using a Human Factors engineering approach. The goal of the study, which took place in a teaching hospital Toronto, Canada, was to understand the processes of collaboration and information exchange that take place in the meetings, and to identify potential supports for the meetings, including the use of information technology. The methodology included data collection through observation of the multidisciplinary patient care meetings, and quantitative analysis of verbal exchanges in those meetings. The results suggested the need for a standardized approach to information exchange using structured language.

This paper describes Empathic Tutoring System (ETS) which uses character agents for online learning. Eye movement tracking and other physiological measures are used to personalize character agent behaviors (affective and instruction) in an e-learning environment. A prototype system reacts to learner's eye information in real-time, recording eye gaze and pupil dilation data (plus heart rate and skin conductance) during learning. Based on these measures, character agents inferred the attentional and motivational status of the learner and responded accordingly with affective and instructional behaviors. Character agents engage and direct the learner's attention while providing both generalized system help and personalized advice about the learning content. Feedbacks from preliminary usability studies may suggest that e-learning character agents reacting to eye gaze and physiological measures may heighten l earner concentration and lead to more effective learning.

Frailty predicts adverse health outcomes, and the Clinical Frailty Scale (CFS) has been validated internationally to predict adverse outcomes and mortality. Emergency Departments (ED) are challenged to assess frailty due to a lack of training and limited time. We studied the agreement between ED physicians and patient self-assessments using a tablet-based CFS that includes graphics and short descriptors for each of 9 frailty categories.

We conducted an experiment in order to investigate impacts of centralexecutive (CE) functions and modality of secondary task presentation in a dualtaskexperiment. We found that shifting ability, out of three major CE functions(inhibition, shifting, and updating) was particularly important in determiningwhether primary (pedal-tracking) task performance was better in the presence ofauditory, vs. visual, presentation of the secondary task.

Gift Giving is a complex and ubiquitous task that would benefit from the simpler and more user-centred style of interaction offered by the Personal Web vision. In this paper we begin by reviewing relevant literature on gift giving, and we identify key roles and requirements of gift giving. We examine current approaches to the support of group gift giving online and review some of their deficiencies. We then discuss the role that recommender systems and social media can play in facilitating gift giving interactions. As a first step towards simpler and more effective group gift giving in the Personal Web, we review results of research studies that we have conducted showing opportunities and challenges with respect to further development of gift giving online communities, and group gift giving services. We conclude with suggestions on future directions for online group gift giving noting the contribution that the Personal Web approach can make in this domain.

Growing interest in emotional interfaces and systems motivates the need for a standard and well-accepted way to measure emotional responses. We introduce the concept of Emotional Majority Agreement: a metric to characterize affective self-report instruments. Emotional majority agreement scores describe the extent to which a sample of participants agrees with regards to their emotional responses. We present a video-watching case study where 12 participants continuously rated how they felt using three self-report prototypes. Majority agreement measures differentiated videos that elicited more or less agreement, prototypes that supported more or less agreement, and individual differences between participants. We conclude with insights gained and future work.

Emotions are an important part of the user experience in human machine interaction. More standardized methods of emotion measurement are required to assist in evaluating and comparing these experiences. This research introduces the concept of Emotional Bandwidth, a psychometric property of self-reported emotion measured through a continuous, quantitative slider. Emotional Bandwidth is illustrated in a videoconference watching case study. The Shannon-Weaver measure of informational entropy was used to quantify the rating usage bandwidth, which relates to the number of levels of emotional rating effectively utilized by participants. Significant differences in rating usage strategy were found, with four groups being identified; across the four experimental blocks, entropy either increased, decreased, remained constant or irregular. Emotional Bandwidth, the information-theoretic analysis of affect ratings collected with a continuous slider, may be used to characterize changes in participants' emotional self-rating during experiments and evaluations.

Publisher Summary This chapter discusses the psychology of augmented human behavior. The evolution of human-computer interfaces and the implications of technological augmentation for the study of human psychology are discussed. Human capability and behavior are changing as more artifacts become part of the standard equipment that people carry around and use. This chapter reviews human–computer interaction and shows the way the constructive nature of perception and cognition may facilitate the implementation of augmenting technologies. Human–computer interaction is seen as a discipline that identifies principles and techniques for designing and evaluating user interfaces in human–computer systems. Attempts to model the psychology of human–computer interaction have generally led to a detailed analysis of tasks and to engineering models of human performance that focus on modeling of information processing activity in terms of response times. Psychology as a discipline is yet to describe the functions and properties of humans, per se, let alone the functions and properties of people interacting with complex technology.

Three well-practiced subjects madesame-different judgments of letter pairs under varying degrees of speed stress. In contrast to the preponderance of false-different errors found using the same method without speed stress (Chignell & Krueger), there were more false-same responses, particularly on similardifferent pairs. The early, or developing, percept looks very similar from one letter to another, apparently because real differences between letters frequently are missed, whereas spurious differences due to missing or unresolved features at encoding or comparison are simply disregarded (missing-feature principle) rather than interpreted as featural mismatches (internal-noise principle). Distinguishing features are added quite late (300 + msec) in processing, just as Eriksen, O’Hara, and Eriksen proposed.

Comparative evaluation of a variety of clustering methods on real and simulated data indicates that the appropriate method for a given set of data must be determined empirically. Selection of an appropriate method generally requires several preliminary analyses. With larger data sets, preliminary analyses on the whole may not be possible. As an alternative one may adopt an interactive strategy and break a large set into manageable subsets.

The use of cluster analysis for the classification of patients into diagnostic groups remains controversial. Further evidence is provided for assessing the use of cluster analysis in comparison with other multivariate methods. It is suggested that, when appropriately used, cluster analysis is a convenient tool for developing empirically based diagnostic groupings and that the frequently stated limitations of the technique should not invalidate the obtained groupings in such cases.

Sequential (vs. simultaneous) presentation of two letters in a physical-identity matching task enhanced the fast-same effect, but did not reduce the preponderance of false-“different” errors or the effect of visual similarity. Thus, the sequential enhancement of the fast-same effect involves an increased efficiency in encoding (d’) owing to letter repetition, as Proctor claimed, rather than a criterion shift (β), and it involves the visual code rather than the name code. The increased efficiency in detecting sameness with sequential presentation might result from spatial separation (e.g., reduced lateral interference and self-termination), though, rather than temporal separation (e.g., priming), However, such spatial factors as letter size and interletter spacing had no consistent effect on the speed advantage forsame pairs, and it was concluded that temporal, not spatial, separation enhances the fast-same effect on sequential trials, Consistent with the response-competition model (Eriksen, O’Hara, & Eriksen), responses were slower and more errorful to similar than to dissimilardifferent pairs, and were equally fast to dissimilar andsame pairs on simultaneous trials.

Video mediated communication alters our perception of the way in which we interact and communicate. In contrast to face to face or audio only (e.g., telephone) communication, there is relatively little systematic research on the effect of video conferencing on communication within groups of people at dispersed locations (Harrison, 1991b; Harrison et al, 1992b; Sellen, 1992; Wolf, 1988; Cohen, 1982; Short, Williams, and Christie, 1976). In this paper we describe a study of how participants at three distant locations perceived differences between face to face (within site) and video mediated (between site) communication. Results indicate that participants perceived between site, mediated communication to be unnatural and uncomfortable. They felt there were problems with gaining floor control and with conversation flow. Additionally, participants perceived the between site, mediated communication to be less interactive, less social, and less enjoyable than the face to face, within site communication. The insights gained through this and other case studies, summarized here, will be used to guide our future research. This study is one in a series of field trials and controlled experiments aimed at understanding the human factors issues associated with video communication and the design of such systems.

Emotional reactions are a key part of user experience. This research examines capture of continuous, quantitative, affective self-reports as a complement to existing methods of evaluating human-system or product interaction. Emotrace is a novel method of measuring emotional responses on the two dimensions of valence and arousal. A pilot study was conducted to inform the design of three emotrace prototypes. This was followed by an experiment where 12 participants watched short videos to elicit emotions, with four self-report conditions (one-slider, two-slider, a touchscreen and no reporting) and physiological capture (heart rate variability and skin conductance). The tools were found to be valid, as ratings reflected the emotion content of the videos. The sliders were found to be more reliable when compared to the touchscreen. We conclude with preliminary recommendations concerning the use of emotrace measurement of emotional user experience to complement current methods of user-interaction evaluation.

This paper examines a number of ways in which a recent model of stress and human performance may be operationalized to allow experimenters and practioners to assess and predict operator capability in stressful conditions. Particular focus is given to the limits of task capability, as the model emphasizes the task itself as the primary source of stress on the performer. The importance of a model with such predictive capability forms the premise of the work, while the assessment of the present status of this and other models of stress forms the summary.

In replicating a national survey dealing with political attitudes in the New Zealand population (2) the authors had to consider the problems associated with classifying their own newly obtained sample of 451 individuals in terms of the responses elicited by an interview which included 35 attitude items and nine biographical measures. The attitude items were designed to measure responses to the political situation and New Zealand society in general, while the biographical measures were sex, age, marital starus, time spent in employment, number of children, educational qualifications, occupation, source of income, and political affiliations. The three responses allowed for each attitude item were (a) agree, (b) 'uncertain, and (c) disagree. Data were analysed using automatic interaction detection analysis (3) after an alternative clustering method (requiring considerable computational expense) did not uncover any structure in the dam (1). The 35 attitude items were used as the independent variables, with political affiliation being the marker (dependent) variable on which the splitting process was based. Separate analyses were run on rwo nonoverlapping subsets of the data (250 cases and 201 cases). Three clusters were identified as common to both analyses. People in cluster one were generally happy and satisfied with NZ politicians. People in cluster two were dissatisfied with NZ politicians but found politics boring. Those in cluster three were unhappy wich NZ politicians but found politics interesting. A stepwise discriminant analysis was then used, with the 26 son-political attitude responses as the independent variables, to identify non-political attitude differences between the three clusters. The remaining attitude which distinguished between the clusters was the belief that New Zealanders care about one another. Only 23% of cluster one disagreed with the statement that New Zealanders care about one another (the rest either agreed or were uncertain) while 53% and 45% of clusters two and three, respectively, disagreed with the statement. Political affiliation indicated that cluster one corresponded roughly to the right end of the political continuum while cluster three was at the lefr end. Members of cluster rwo divided their support over four political parties. A detailed description of the survey results are available from the authors.