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International Journal of Human-Computer Interaction 13

Editors:Kay M. Stanney; Gavriel Salvendy
Dates:2001
Volume:13
Publisher:Ablex Publishing Corporation
Standard No:ISSN 1044-7318
Papers:26
Links:Table of Contents
  1. IJHCI 2001 Volume 13 Issue 1
  2. IJHCI 2001 Volume 13 Issue 2
  3. IJHCI 2001 Volume 13 Issue 3
  4. IJHCI 2001 Volume 13 Issue 4

IJHCI 2001 Volume 13 Issue 1

The Effectiveness of Virtual Reality Pain Control With Multiple Treatments of Longer Durations: A Case Study BIBA 1-12
  Hunter G. Hoffman; David R. Patterson; Gretchen J. Carrougher; Dana Nakamura; Merilyn Moore; Azucena Garcia-Palacios; Thomas A., III Furness
Immersive virtual reality (VR) has proved to be potentially valuable as a pain control technique for patients with severe burns undergoing wound care and physical therapy. Recent studies have shown that single, 3-min visits to a virtual world can dramatically reduce the amount of pain experienced during wound care, and the illusion of going inside the computer-generated world helps make VR analgesia unusually effective. This case study explored whether VR continues to reduce pain when the duration and frequency of VR treatments are increased to more practical levels. A patient with deep flash burns covering 42% of his body spent varying amounts of time performing physical therapy with and without virtual reality. Five subjective pain ratings for each treatment condition served as the dependent measures. The magnitude of pain reduction with VR, and the patient's illusion of "going into" the virtual world did not diminish with repeated administration and longer treatment durations. Practical implications are discussed. The results of this study may be examined in more detail at www.hitl.washington.edu/projects/burn/.
Can a More Neutral Position of the Forearm When Operating a Computer Mouse Reduce the Pain Level for Visual Display Unit Operators? A Prospective Epidemiological Intervention Study: Part II BIBA 13-40
  Arne Aaras; Marvin Dainoff; Ola Roas; Magne Thoresen
The aim of this study was to investigate if participants with pain experience reduced pain development when using a mouse allowing a more neutral position of the wrist (Anir) compared with development of pain using a traditional mouse. The study population consisted of 67 participants with mean intensity of pain of approximately 50 mm on a 100-mm Visual Analog Scale (VAS). The total group was randomly divided into 1 intervention group and 1 control group. The study was performed as a prospective parallel group study. VAS was used to assess the average level of pain in the musculoskeletal system during a 6-month period. An earlier article on this study found that after using the Anir mouse for 6 months, a significant reduction was reported in neck pain (48.9 to 33.9). Corresponding data for other areas of the upper extremities were shoulder (54.1 to 31.8), forearm (52.9 to 32.8), and wrist and hand (42.5 to 22.3), respectively (Aaras, Ro, & Thoresen, 1999). The control group using the traditional mouse reported no significant changes in pain level. This article describes the results after giving an identical intervention to the control group. After 6 months, the former control group reported a significant reduction in average pain for the following body areas: shoulder, M = 48.0 (CI = 32.5-63.5) to M = 28.7 (CI = 18.7-38.8); forearm, M = 45.6 (CI = 30.8-60.4) to M = 15.6 (CI = 5.5-25.7); and wrist and hand, M = 34.8 (CI = 20.1-49.5) to M = 15.8 (6.4-25.2). Neck pain was marginally significantly reduced, M = 39.4 (CI = 25.2-53.6) to M = 27.4 (CI = 15.2-39.6), p = .07. The group getting the initial intervention did not report any significant changes in any of the body areas from 6 to 12 months after the study period; that is, the reduction in pain level obtained still existed. The results from this study indicate clearly the importance of using a more neutral position of the forearm when using a computer mouse. Laboratory tests on performance measures (speed and accuracy) showed that the Anir mouse falls well within the range of performance measures associated with already existing commercially available input devices.
Beyond Translation: Approaches to Interactive Products for Chinese Consumers BIBA 41-51
  Heiko Sacher; Tai-Hou Tng; Gareth Loudon
The localization of interactive, digital products often centers around disconnects between a foreign language and North American conventions-the deficit-driven approach. The fact that a distinct user language can be the key to a deep understanding of a culture that ultimately leads to solutions that go beyond purely functional language support is often overlooked. In this article we describe the challenges of enabling products for interaction with Chinese customers. We show how deficit-driven approaches have been used for quickly identifying and addressing usability issues in interfaces. However, when fundamental disconnects between a product and a user culture exist, the deficit perspective can result in hard-to-understand and cumbersome products. We propose an alternative, complementary approach that is based on the interdependency of language, culture, and interaction. It allows product and interface design practitioners to reveal users' language rules, elements, and structures. Those characteristics reflect users' mental models, problem-solving approaches, and behavioral patterns. This approach fosters the integration of cultural aspects into the design process to create products that connect to the conventions of interaction in the Chinese culture-toward truly "smart" products for the Chinese market.
Model Testing of Users' Comprehension in Graphical Animation: The Effect of Speed and Focus Areas BIBA 53-73
  Nancy J. Lightner
Graphics provide a means of displaying large numbers of data points at one time. Multidimensional graphs are used for recognizing trends and analyzing a business environment for decision making. When several images are shown in an ordered sequence, an animated display is created. As the use of graphical, animated displays becomes more prevalent for business analysis and decision making, a better understanding of the conditions under which these displays are useful is needed. This research presents a model of animation speed setting based on Bloch's law of temporal summation; rapid, sequential, visual presentation; and eye movement timings. The model was tested in a laboratory experiment. The experimental results indicate that the model can be used to determine animation speed but only within the limits of human comprehension. Response accuracy to basic comparison questions was highest when the number of nonadjacent areas viewed on the display was 1 or 2. Based on these findings, a revised model is presented as well as a new guideline for interface design.
The Implications of Visualization Ability and Structure Preview Design for Web Information Search Tasks BIBA 75-95
  Honggang Zhang; Gavriel Salvendy
This study investigates the effects of users' visualization ability and Web site structure display design on users' performance and memory organization in Web site information search tasks using a browsing strategy. A human-centered design-structure preview-was proposed in this study. Structure preview is a Web site navigation menu in which each menu item serves as a link to one Web page, similar to a menu design in Microsoft Windows 95 and Windows 98. An experiment was conducted in which 40 individuals participated. The experimental design was a 2-factor factorial design. Independent variables were visualization ability (low and high) and Web site design (conventional and structure preview). Twenty participants were identified as users with low visualization ability and 20 participants were identified as users with high visualization ability. Dependent variables were the number of identified items, the number of steps per item, and memory organization. Results indicated that both low- and high-visualization users' performance improved significantly (76.3% more identified items and 83.4% fewer steps per item for low-visualization users; 36.5% more identified items and 78.4% fewer steps per item for high-visualization users) when using the structure preview design than when using the conventional design. When using the conventional design, high-visualization users had significantly better performance (36.9% more identified items and 23.6% fewer steps per item) than low-visualization users. Also, the memory organization of all users (including both low- and high-visualization users) improved significantly (42.9%) when using the structure preview design compared with the conventional design.
Book reviews BIB 97-103
  Randy J. Pagulayan; Brian H. Philips

IJHCI 2001 Volume 13 Issue 2

Introduction: Ubiquitous Computing: Anytime, Anyplace, Anywhere? BIB 107-111
  Neville A. Stanton
Ensemble Computing BIBA 113-121
  Peter Thomas; Hans-W Gellersen
The technology space that includes ubiquitous computing, information appliances, and pervasive and situated systems is the subject of intense interest among the research community. In this article, we examine some of the principles implicit in this space and introduce the idea of "ensemble computing" to describe technologies that extend this space.
Wearable Computers: A Human Factors Review BIBA 123-145
  Chris Baber
In this article, wearable computers are considered from the perspective of human factors. Three approaches to the development of this technology are presented: computers that can be worn, information appliances that can be worn, and computers as clothing. The implications for how people will wear and interact with computers in these forms are considered. In particular, in this article a discussion of forms of dialogue to demonstrate how wearable computers require fundamental revision of the way in which we consider human-computer interaction is presented. This article concludes with reports of work on human interaction with wearable computers, both in terms of task performance and physical effects of wearing technology.
Sensory Fabric for Ubiquitous Interfaces BIBA 147-159
  Stan S. Swallow; Asha Peta Thompson
Sensory Fabric is a technology that uses electrically conductive textiles to fabricate switches and sensors. In this article we examine how a number of broad device types, or form factors, can be reconfigured or made more ubiquitous by replacing their traditional interface hardware with Sensory Fabric. The implications of using a fabric solution are explored for handheld and personal devices, educational computing, and the personal computer interface. Each case study describes a number of technology demonstrator devices, using them to illustrate how some of the drawbacks of traditionally packaged interfaces can be countered. Sensory Fabric can replace small, cold, hard, heavy, and smooth interfaces with large area, warm, soft, lightweight, and tactile ones.
"You Talking to Me?" Exploring Voice in Self-Service User Interfaces BIBA 161-186
  Graham I. Johnson; Lynne Coventry
Automated teller machines (ATMs) are a classic example of ubiquitous computing as they pervade our everyday life and, for many, are typical artifacts of convenient, modern living. More important, most people are unaware that in using an ATM they are connected via a computer to a powerful network. Through our research reported within this article, we examine the user acceptance and usability aspects of a novel, "contactless" ATM. This prototype ATM has iris identification, speech recognition, speech synthesis, and communication to a user's personal digital assistant (PDA).
   In this article, we describe our experiences of and explorations with "Stella," a contactless ATM. First, we briefly discuss the background to the study in terms of technology and trends, and then overview previous usability research in the area. We report our findings from a cognitive walkthrough, the heuristic review of the prototype, focus groups, and a user trial. These results underline the need for multiple evaluation methods for novel concepts. In general, from the findings of this work, consumers believe that speech is a technology that will create more usable applications, even when faced with the relative failure of current technology to live up to their expectations or fulfill their practical needs. People are often initially resistant to the concept of iris identification and the PDA interaction, yet basic experience with a usable prototype quickly overcame people's reservations. Finally, we outline some of the underlying challenges facing voice-based interaction approaches to this form of ubiquitous, public self-service computing.
A Case Study of On-Screen Prototypes and Usability Evaluation of Electronic Timers and Food Menu Systems BIBA 187-201
  Joanne O. Crawford; Chris Taylor; Nicolas Li Wan Po
Ubiquitous computing in domestic products, although allowing smarter products, can increase the complexity of interfaces that the end user has to face. This case study is an evaluation of an on-screen prototype of a cooker timer and food menu system. The techniques used to evaluate the prototype included questionnaire, user trial, System Usability Scale questionnaire (Brooke, 1996), observation, interview, repertory grid, Hierarchical Task Analysis (Kirwan & Ainsworth, 1992), and Task Analysis for Error Identification (Baber & Stanton, 1991, 1996; Stanton & Baber, 1998). From the usability evaluation a simplified interface was designed that will be taken forward and reevaluated in the future. Issues raised in the case study were first that of increased complexity allowed by increased levels of processing power, and second that of on-screen prototypes and the difference between interacting with traditional desktop computing applications as opposed to a physical product. We highlight in the conclusion that there is a need for those involved in development of on-screen and physical prototypes to work with those involved in human factors and usability to ensure a usable end product.
Where Is Computing Driving Cars? BIBA 203-229
  Guy H. Walker; Neville A. Stanton; Mark. S. Young
Cars offer an excellent example of ubiquitous computing, and a technological revolution is currently underway that will eventually see in-vehicle computers empowered with increasingly complex sections of the driving task. In this article, we critically review the effect of ubiquitous computing in cars with reference to the psychology of the driver and present a survey of automotive researchers drawn from five major carmakers. The results illustrate the role of the computer in vehicles over the short, medium, and long term. Systems that are likely to be fitted into vehicles in the next 5 years include sophisticated electronic architectures and greater penetration of navigation and telematics systems. In the next 5 to 15 years drive by wire and collision sensing are anticipated. In the long term, 15 years and beyond, advanced driver-assistance systems will increasingly automate the driving task, and in-car personal computers and Internet will be commonplace. We conclude that the increased complexity and prominence of computing in cars requires further investigation of the needs, abilities, and limitations of the driver if the aims of safety, efficiency, and enjoyment, as well as greater ubiquity, are to be realized.
Data Collection in the Palm of Your Hand: A Case Study BIBA 231-243
  Kelly A. Spain; Chad A. Phipps; Michael E. Rogers; Barbara S. Chaparro
Portable computing is an emerging technology that allows computing to occur practically anywhere. Going beyond the typical use as the "pocket-sized organizer," new methods of using handheld devices are being developed. One new method is to use handheld devices to collect data in the field. The portability of handheld devices allows for data collection in virtually any setting and frees the researcher from the confines of the laboratory. This article describes the process of converting a paper-and-pencil method of data collection to a 3Com Palm Pilot(tm)III application. An iterative design process was used to evaluate the ease of use of the new application. The new application (a) substantially reduced time to transfer the data to a database, (b) did not interfere with the task, (c) allowed the user to accomplish the same tasks as with the paper method while adding functionality beyond the paper method, and (d) was rated as easy to use.
Ubiquitous Computing on Campus: Patterns of Engagement by University Students BIBA 245-256
  Charles Crook; David Barrowcliff
It is argued that, for full-time undergraduates, ubiquitous computing will continue to involve the private, circumscribed workstation as a significant feature of its design. We report records of how a random sample of campus-resident students makes use of a networked and versatile infrastructure of computers. Highly detailed system logs revealed intensive periods of use. The content of this activity was strongly biased toward more playful interests than the curricula agenda of the institution. This did not reflect unfavorable competition between the activity of study and other discrete activities such as computer games. Instead, the capacity of the desktop environment to provide strong distracting affordances for interaction and interruption is noted. This sustains a significantly mobile and multitasking style of engagement. We noted that the versatility of ubiquitous computing creates tensions in relation to the activity system of private study. The same characteristics that empower research-led study practices also empower the pursuit of interests in distracting competition with the demands of learning and research. Moreover, study may demand ways of acting that are not consistent with the affordances of ubiquity.
The Effects of Wireless Computing in Collaborative Learning Environments BIBA 257-276
  Geri Gay; Michael Stefanone; Michael Grace-Martin; Helene Hembrooke
Eighty-four students distributed between two different courses at a major research university (one a communication course, the other a computer science course) were given laptop computers with wireless network access during the course of a semester. A wide variety of data (from questionnaires, e-mail logs, proxy server logs, and diaries) regarding students' use of the laptops for electronic communication, Web browsing, and local application use (e.g., word processing) was collected and analyzed. The influences of course, network (wireless-wired), student population, and the passage of time were investigated in relation to the prevalence and nature of social computing (e.g., e-mail, instant messaging, chat, discussion boards, online annotations) in students' laptop usage. The relative prevalence of social computing increased and became more exclusive for students in the communication course, especially on the wireless network. Social computing and use of the wireless network were less prominent and influential for students in the computer science course.

IJHCI 2001 Volume 13 Issue 3

Experience of Stress, Musculoskeletal Discomfort, and Eyestrain in Computer-Based Office Work: A Study in Municipal Workplaces BIBA 279-304
  Pentti Seppala
A questionnaire on the use of information technology and stress at work was administered in 3 organizational units of a large municipality in 1996. Three hundred seventy-nine employees from several professional groups (e.g., architects, engineers, lawyers, clerical workers, draftspersons, etc.) answered the questionnaire. The age of the respondents ranged from 21 to 62 years (M = 45.2, SD = 8.7). Sixty-one percent of the respondents were women, and 39% were men. Psychosocial and organizational factors were related to the experiences of psychological stress as well as to musculoskeletal disorders and problems with vision. Women reported stress and all symptoms more often than men. The occupational groups differed according to the main sources of stress. Age associated with the concern about changes in tasks and responsibilities, lack of competence, and difficulties in using computers. In regression analyses, workload and haste, management and work atmosphere, work demands, defects of the workplace, and gender explained 42% of the experience of mental stress and anxiety. Twenty-five percent of the complaints of discomfort of the upper limbs were explained by workload and haste, management and atmosphere, defects of the workplace, hours of daily computer use, and gender. Nineteen percent of the problems with vision were explained by age, workload and haste, defects of the workplace, hours of daily computer use, skills in computer use, and stress related to computer use.
Proposal of an Index to Evaluate Visual Fatigue Induced During Visual Display Terminal Tasks BIBA 305-321
  Atsuo Murata; Atsushi Uetake; Miho Otsuka; Yosuke Takasawa
The study described in this article was designed to evaluate visual fatigue induced during video display terminal (VDT) tasks. Newly developed equipment was used that can simultaneously measure pupillary change, focal accommodation, and eye movement. The changes in these 3 physiological measures, taken during a VDT task, were used to propose an index for evaluating visual fatigue. Through multiple regression analysis, an index to describe the psychological sense of visual fatigue was obtained. In this index, the minimum pupil diameter, velocity of focal accommodation for constriction, and width of focal accommodation were included. The results suggest that visual fatigue in VDT tasks can be evaluated effectively using both pupil diameter and focal accommodation. The index can be used to assess visual fatigue induced during a VDT task if the following 3 conditions are satisfied:
  • 1. Head movement is limited and infrequent.
  • 2. The task requires focal accommodation.
  • 3. During the task, there is no outstanding change in the lighting environment
        such as luminous intensity or brightness.
  • Implications of User Characteristics in Information Seeking on the World Wide Web BIBA 323-340
      Kyung-Sun Kim
    The study described in this article investigated how differences in cognitive style and online search experience influence the search performance and navigational pattern of individuals utilizing a university World Wide Web (WWW) site. Forty-eight undergraduate students with diverse academic backgrounds participated in the study. On the basis of cognitive style and prior experience with online database search, the participants were assigned to 1 of the following groups: (a) field-dependent (FD) with little or no online search experience, (b) FD with substantial online search experience, (c) field-independent (FI) with little or no online search experience, and (d) FI with substantial online search experience. It was found that cognitive style influenced search time, whereas online search experience affected navigational style, such as jumps and layer traversal. Cognitive style and online search experience also interacted to influence search performance and navigational style. FDs with little or no online search experience navigated the WWW in a fairly linear mode, using embedded links frequently. They also tended to visit more nodes and used "Home" more frequently than the rest. The results imply that as FD searchers gain more online search experience, their navigational style and search performance change and become comparable to that of FDs. Based on these findings, some suggestions are made to improve the WWW interface and WWW user training programs.

    IJHCI 2001 Volume 13 Issue 4

    Current Issues in Usability Evaluation BIBA 343-349
      James R. Lewis
    In this introduction to the special issue of the International Journal of Human-Computer Interaction, I discuss some current topics in usability evaluation and indicate how the contributions to the issue relate to these topics. The contributions cover a wide range of topics in usability evaluation, including a discussion of usability science, how to evaluate usability evaluation methods, the effect and control of certain biases in the selection of evaluative tasks, a lack of reliability in problem detection across evaluators, how to adjust estimates of problem-discovery rates computed from small samples, and the effects of perception of hedonic and ergonomic quality on user ratings of a product's appeal.
    Usability Science. I: Foundations BIBA 351-372
      Douglas J. Gillan; Randolph G. Bias
    In this article, we describe and analyze the emergence of a scientific discipline, usability science, which bridges basic research in cognition and perception and the design of usable technology. An analogy between usability science and medical science (which bridges basic biological science and medical practice) is discussed, with lessons drawn from the way in which medical practice translates practical problems into basic research and fosters technology transfer from research to technology. The similarities and differences of usability science to selected applied and basic research disciplines-human factors and human-computer interaction (HCI) is also described. The underlying philosophical differences between basic cognitive research and usability science are described as Wundtian structuralism versus Jamesian pragmatism. Finally, issues that usability science is likely to continue to address-presentation of information, user navigation, interaction, learning, and methods-are described with selective reviews of work in graph reading, controlled movement, and method development and validation.
    Criteria For Evaluating Usability Evaluation Methods BIBA 373-410
      H. Rex Hartson; Terence S. Andre; Robert C. Williges
    The current variety of alternative approaches to usability evaluation methods (UEMs) designed to assess and improve usability in software systems is offset by a general lack of understanding of the capabilities and limitations of each. Practitioners need to know which methods are more effective and in what ways and for what purposes. However, UEMs cannot be evaluated and compared reliably because of the lack of standard criteria for comparison. In this article, we present a practical discussion of factors, comparison criteria, and UEM performance measures useful in studies comparing UEMs. In demonstrating the importance of developing appropriate UEM evaluation criteria, we offer operational definitions and possible measures of UEM performance. We highlight specific challenges that researchers and practitioners face in comparing UEMs and provide a point of departure for further discussion and refinement of the principles and techniques used to approach UEM evaluation and comparison.
    Task-Selection Bias: A Case for User-Defined Tasks BIBA 411-419
      Richard E. Cordes
    Usability evaluations typically occur throughout the life cycle of a product. A number of decisions and practical biases concerning the tasks selected for usability evaluations can influence the results. A pervasive bias is to select only tasks that are possible to perform with the product under evaluation, introducing a subtle bias for the participants. One way to avoid this problem is to employ user-defined tasks (UDTs) in usability evaluations. In addition, having participants define tasks to perform in a product evaluation allows a more accurate assessment of product usability. This is because UDTs based on users' requirements and expectations should be relatively independent of the functional capabilities of a product. However, there are a number of methodological and practical issues that result from the introduction of UDTs in a usability evaluation. The best approach is to design hybrid evaluations using both UDTs and product-supported tasks.
    The Evaluator Effect: A Chilling Fact About Usability Evaluation Methods BIBA 421-443
      Morten Hertzum; Niels Ebbe Jacobsen
    Computer professionals have a need for robust, easy-to-use usability evaluation methods (UEMs) to help them systematically improve the usability of computer artifacts. However, cognitive walkthrough (CW), heuristic evaluation (HE), and thinking- aloud study (TA)-3 of the most widely used UEMs-suffer from a substantial evaluator effect in that multiple evaluators evaluating the same interface with the same UEM detect markedly different sets of problems. A review of 11 studies of these 3 UEMs reveals that the evaluator effect exists for both novice and experienced evaluators, for both cosmetic and severe problems, for both problem detection and severity assessment, and for evaluations of both simple and complex systems. The average agreement between any 2 evaluators who have evaluated the same system using the same UEM ranges from 5% to 65%, and no 1 of the 3 UEMs is consistently better than the others. Although evaluator effects of this magnitude may not be surprising for a UEM as informal as HE, it is certainly notable that a substantial evaluator effect persists for evaluators who apply the strict procedure of CW or observe users thinking out loud. Hence, it is highly questionable to use a TA with 1 evaluator as an authoritative statement about what problems an interface contains. Generally, the application of the UEMs is characterized by (a) vague goal analyses leading to variability in the task scenarios, (b) vague evaluation procedures leading to anchoring, or (c) vague problem criteria leading to anything being accepted as a usability problem, or all of these. The simplest way of coping with the evaluator effect, which cannot be completely eliminated, is to involve multiple evaluators in usability evaluations.
    Evaluation of Procedures for Adjusting Problem-Discovery Rates Estimated From Small Samples BIBA 445-479
      James R. Lewis
    There are 2 excellent reasons to compute usability problem-discovery rates. First, an estimate of the problem-discovery rate is a key component for projecting the required sample size for a usability study. Second, practitioners can use this estimate to calculate the proportion of discovered problems for a given sample size. Unfortunately, small-sample estimates of the problem-discovery rate suffer from a serious overestimation bias. This bias can lead to serious underestimation of required sample sizes and serious overestimation of the proportion of discovered problems. This article contains descriptions and evaluations of a number of methods for adjusting small-sample estimates of the problem-discovery rate to compensate for this bias. A series of Monte Carlo simulations provided evidence that the average of a normalization procedure and Good-Turing (Jelinek, 1997; Manning & Schutze, 1999) discounting produces highly accurate estimates of usability problem-discovery rates from small sample sizes.
    The Effect of Perceived Hedonic Quality on Product Appealingness BIBA 481-499
      Marc Hassenzahl
    Usability can be broadly defined as quality of use. However, even this broad definition neglects the contribution of perceived fun and enjoyment to user satisfaction and preferences. Therefore, we recently suggested a model taking "hedonic quality" (HQ; i.e., non-task-oriented quality aspects such as innovativeness, originality, etc.) and the subjective nature of "appealingness" into account (Hassenzahl, Platz, Burmester, & Lehner, 2000).
       In this study, I aimed to further elaborate and test this model. I assessed the user perceptions and evaluations of 3 different visual display units (screen types). The results replicate and qualify the key findings of Hassenzahl, Platz, et al. (2000) and lend further support to the model's notion of hedonic quality and its importance for subjective judgments of product appealingness.