A Preliminary Framework for Differentiating the ...

A Preliminary Framework for Differentiating the Paradigms of Human-Technology Interaction Research Hannu Karvonen

Pertti Saariluoma

Tuomo Kujala

Systems Usability VTT Technical Research Centre of Finland Espoo, Finland e-mail: [email protected]

Department of Computer Science and Information Systems University of Jyväskylä Jyväskylä, Finland e-mail: [email protected]

Agora Human Technology Center University of Jyväskylä Jyväskylä, Finland e-mail: [email protected]

Abstract—The purpose of this paper is to clarify the differences between approaches in the research field of human-technology interaction. We are especially interested in individuating user psychology from the more traditional paradigms. Therefore, we suggest a preliminary theoretical framework of criteria for distinguishing and individuating the different interaction research paradigms. The framework consists of five dimensions in which the paradigms may vary from each other. In this paper, we also discuss how ubiquitous computing is related to some of the dimensions. In addition, we focus on defining the new elements user psychology can bring to the discussion and analysis of human-technology interaction. To demonstrate the usage of the framework, we apply it to differentiate user psychology from traditional HCI research. Keywords: human-technology interaction; user psychology; human-computer interaction; paradigms; psychological and metascientific foundations for designing human-technology interaction;

I. INTRODUCTION There is a wide variety of human-technology interaction (HTI) related research carried out under paradigms with different names, conceptualizations, research focuses and methods. Therefore, it is no wonder that the field might seem rather confusing at first glance. For example, the following names have been coined over the years: Human-computer interaction (HCI) [1] Human-system interaction (HSI) [2] Human-machine interaction (HMI) [3] Human (or user)-centered design [4] Human factors (HF) engineering [5] Cognitive engineering [6] Usability engineering [7] Ergonomics (physical and cognitive) [8] Aviation psychology [9] Engineering psychology [10] If we examine the actual research performed under differently labeled fields, we see a lot of common ground; the ultimate problem between the fields is the same, i.e., how people can best use and benefit from technology. For this reason, it is also logical to argue that human-technology interaction, seen as the common problem, provides the most

extensive conceptual umbrella for the problems all other traditions investigate. Nevertheless, taking human-technology interaction as the basic problem does not make it unjustified to ask why we need to conceptually and paradigmatically separate these areas under different labels. It can be questioned that are there some dimensions in these areas that really distinguish them from each other or are they just the same research endeavor conducted under different concepts which emphasize the importance of some minor aspect of the approach? It is also important to think what makes some new paradigm essentially different from the earlier ones. This means to ask what genuinely new a proposed paradigm introduces to the complex discourse on human-technology interaction. To answer these kinds of questions we suggest a preliminary theoretical framework for analyzing the differences between HTI paradigms on the grounds of five dimensions and discuss their relation to the previous research in the field. Therefore, the ultimate aim of this paper is to clarify the conceptual foundations of making comparisons between different HTI research approaches [11]. Furthermore, our goal is to discuss the place of a new paradigm we have been developing in recent years called user psychology. This research pursuits to develop an optimal approach relying on modern psychological knowledge and methods in analyzing and solving interaction design problems [12]. During presenting the framework, we also discuss what role ubiquitous computing has within some of the dimensions. After presenting all the five dimensions of the framework we use it to differentiate user psychology from traditional HCI. Finally, we draw conclusions from the framework and its usage. II. DISCRIMINATION CRITERIA It may appear as a simple problem to make differences between the various HTI approaches. However, all kinds of possible differences between the paradigms do not work appropriately; we need to have rational criteria to do it. The problems in making distinctions between differently labeled areas of HTI research may become explicit by looking for example to the following criteria, which are sometimes used:

History o E.g., the long traditions of HF Engineering vs. the fairly short history of HCI Specific domain of investigation o E.g., aviation psychology Geographical location of research organizations o E.g., Europe vs. North America However, these viewpoints do not necessarily offer clear reasons why the presented areas should be conceptually separated from each other. First, some approaches might be commonly accepted as part of others in their history. For example, one could see HCI’s development as one case of HMI or HSI. Second, different parts of paradigms can also be seen as part of each other. For example, much of aviation psychology can be seen as some specific issues in HMI. Third, there are clear geographic preferences in terminology (e.g., user experience vs. emotional usability), but the differences in terminology originating from geography or local terminological fashions cannot provide us valid scientific grounds when we compare scientific paradigms. We argue that the justification must be looked from differences e.g., in concepts, methods, theories evidence and practices. Therefore, we need to look for a framework of rational system of criteria which makes it understandable how the various paradigms differ and what is their “location”, i.e., to what kind of problems they can be effectively and relevantly applied to, in the great discourse on human-technology interaction. To begin with the analysis of these metascientific issues we suggest five dimensions as criteria in which different research disciplines may vary from each other. It may be argued that the dimensions can set different types of goals for the approaches. Equally important, another aspect worth noticing is time. Some approaches may differ historically in a suggested dimension, but they can merge in the future. The dimensions we suggest are: The scope of target technology Design vs. research orientation Technology-driven vs. human-driven orientation Intuitive vs. scientific practice in analyzing human Metascientific rigour in investigating users Next, we discuss each of these dimensions in detail. A. The Scope of Target Technology Different research disciplines may differ from each other in the focus of technologies they concentrate on. An example of this is the difference between human factors and HCI research. Human factors research does not limit itself to a certain technology. It can be applied to almost everything operated by human, whereas traditional human-computer interaction is limited to research on issues between people and computers. This difference was evident especially in the 1980s, when HCI begun to be identified as its own research area. In those days, the computer was seen as a box with a display and

some input device (e.g., a keyboard) attached. The real need for HCI research emerged when computers began to move from office to home. However, the difference in the scope of technology between human factors and HCI research may not be as clear in the near future. Soon our environment will be full of smart computing devices which can communicate with each other. This scenario is part of the vision of ubiquitous computing (ubicomp) [13]. In an ideal ubicomp world, there are invisible computers implicitly supporting our daily activities everywhere around us. Therefore, every object in our environment can contain some sort of computer chip. This will cause a radical change in the research paradigm of HCI [14]; the scope of HCI research will widen to cover every object around us. This trend can already be seen for example in cars which can contain over 30 computers on board [15]. Ubicomp provides an example of technology-based developments. It opens new promising ways to implement human-technology interaction and design for everybody. In the future, intelligent systems may be designed to automatically recognize the user’s preferences and disabilities and adapt their interfaces accordingly. Moreover, some of the systems can even predict the user’s needs, e.g., based on past interaction, and act appropriately. These kinds of systems would be an example of a technology that really conforms to the needs of the user. The scope of target technology or technological advancement is therefore evidently a relevant criterion. New technologies have brought about new approaches in HTI and these paradigms differ from the others thanks to their commitment to a particular technology. B. Design vs. Research Orientation Research paradigms may also differ in their action and practice goals. Carroll [16] already noticed that academic researchers have often less application-oriented goals than industrial people and because of that research and design do not always communicate in an optimal manner. From the presented point of view, e.g., human-centered design, cognitive engineering, ergonomics and HF engineering are disciplines that are ideally used in cooperation with the design processes of organizations. The purpose of these kinds of disciplines is to apply the information gathered for instance from users, computational models and testing to the design of a specific technology or product. For example, the definition of ergonomics makes this design orientation evident: “Ergonomics (Human Factors Engineering) [is] an applied science concerned with the characteristics of people that need to be considered in designing things that they use in order that people and things will interact most effectively and safely [17].” Therefore, ergonomics or HF engineering is said to be concerned with the application of data and principles of human factors research to the design of the things we use. Human factors research itself is defined as the study of the relationships of humans with machines (things), workplaces and other environments. Human-computer interaction research on the other hand has always been more research-oriented and its goal has

mostly been to describe and analyze interaction [16]. It does not necessarily have had strong ideal to design, but rather to give information for design from the start of the development. It can be seen research-interested in adapting cognitive concepts to the analysis of human-technology interaction [18]. In addition to HCI, research paradigms such as human factors and engineering psychology have also been interested in producing more general type of knowledge about the relationship of humans and technology. Consequently, it makes sense to take design and research orientation as one criterion for dividing HTI paradigms. The differences are not necessarily very strict but rather they are polar. Some traditions and some researchers have had much more interest in investigating basic issues and some others in how to make ideas for example industrial design. C. Technology-Driven vs.Human-Driven Orientation The previous considerations lead us to the next dimension. The traditional point of view in product design is to first build the technical solutions which are often based on old traditions of engineering. Although this kind of approach causes cumbersome user interfaces which are hard to use, the dexterous human being can compensate this by inventing work-a-rounds and other ways of using the system to achieve the goal he or she is striving for. In addition, when using this type of technology everyday people are inventive in developing own routines and habits, which were not initially meant by the designer, to minimize the problems deriving from the technology’s usability design flaws. Therefore, it can be said that technology is traditionally developed so that the users have to adapt their activities according to the qualities of technology [19, 20]. Because of this, the technology is often modified later on, for example by justifying the modifications with the results of usability studies, to enable better adaptation for users. However, if usability and human factors issues are taken into consideration late in the development process, the changes cannot usually be very dramatic anymore. Therefore, it can be argued that ergonomics or HF engineering are very valuable approaches in making technology easier to use, but unfortunately they often come only after the technological solutions. It is very common that the user interface is attached afterwards to the fully implemented system. This method is problematic because if the underlying logic of the system is not implemented according to the user needs then the system cannot be saved with a nice-looking appearance. HCI is an even better example of a research area where very often the technology is considered to be closed (i.e., usually a mouse, a keyboard and a screen for visual presentation) and the focus of attention is on software usability, even though there could be better ways to realize the interaction physically [1, 18]. Therefore, this kind of thinking might hinder the designer’s creativity and restrict the possibilities to search for alternative outside-the-box solutions. The opposite point of view is to perceive technology as something developed for supporting the activities of people. From this viewpoint, the activities and goals of human behavior should be the starting point for the development

process, not the existing technology. Therefore, technology should adapt to the activities of a human, not vice versa. Many recent new research ideas have adopted this humanoriented point of view. Typical examples of these are usercentered design [21], ethical design [22, 23], worth-sensitive design [24] and life-based design [25, 26]. These approaches actively develop theory languages and practices to begin the design with people and to provide models regarding the activities, goals, needs and behavior of people in everyday and specific environments. This also conforms to the design ideology of ubicomp; in an ideal ubicomp environment the system is aware of its context and can adapt its behavior according to human needs [14]. It is therefore important to use technology vs. human orientation as well in research and design as one criterion for making distinctions between the approaches. Though the orientation is not necessarily absolute or contradictory, it opens different perspectives to interaction research by emphasizing very different aspects of the interaction process. D. Intuitive vs. Scientific Practice in Analyzing Human As technology grows more complex and systems become more intelligent the need for a deeper understanding of human in interaction with these technologies is growing as well. Therefore, the consideration of merely anthropometric, cognitive or physiological factors will not be sufficient. This means that the depth of required understanding and analysis of human mind and action also forms a criterion to compare the different approaches. In general, it can be said that human-centered design has evolved during the 20th century starting from World War II when it covered only a few physiological qualities of human actors in aircraft cockpits into nowadays view of considering humans as complex technology users in various high-tech environments [3, 21, 27, 28, 29]. It is positive to notice that the knowledge about the human dimension of technology is continuously increasing. One of the latest trends in humancentered design is to involve the actual potential users of the technology in the design process [20]. In addition, the fact that we cannot design for the average person is acknowledged in design. This can also be seen as progress towards a more human-centered design that takes more into account the dissimilar qualities of users. Therefore, we should design technology that is easy to use for everyone – also for example for people with disabilities. Fortunately, human-centered design as a holistic approach is attracting more and more attention nowadays (see Table 1). TABLE I.

THE EVOLUTION OF DESIGN ORIENTATION IN HUMAN CENTERED DESIGN World War II

Nowadays

Focus of Study

A few physiological qualities.

A holistic approach where human is a complex technology user in various environments

User Involvement

Low

High

World War II Design for Whom

For an idealized person

Nowadays For everyone

Nonetheless, Norman [20] argues that human-centered design can be misleading or even harmful. Norman’s idea is to replace the term “human-centered” with “activitycentered”. In this way, instead of focusing on the static qualities of the technology and on the requirements of different users he emphasizes the importance of considering to what activities the technology is designed for. Although this could easily be true, we believe it is not the proper use of terminology that leads to great design. Instead, we argue that the results depend on what aspects of human-centered design (e.g., user feedback, task analysis, usability testing, etc.) are really emphasized in the design process. After all, giving human activities a high priority in the design process can be argued to be a form of human-centered design. If we reflect this on the ideology of ubicomp, it might seem at first glance a very promising ideal of smooth and natural interaction between people and computers. However, the human-centered design of ubicomp systems poses an enormous challenge of making the interaction work as intended. For example, in safety-critical environments such as cars there has been lately introduced several new ubiquitous computing systems which can also affect the behavior and safety of the driver negatively when interacting with these systems [15]. One typical example of these systems is Adaptive Cruise Control (ACC) which can be found on several nowadays cars. ACC tries to keep a defined distance to the car ahead and slows down when the car ahead is getting too close. However, the driver may not be fully aware of the fact that the system does not necessarily stop the car soon enough if the vehicle ahead commits a sudden panic braking or another vehicle suddenly enters the driven lane with slower speed from another lane. This may lead to slowed reaction times as the driver trusts the system too much, is not as focused on the primary task of driving as he or she would be without the system and therefore not prepared to perform the needed braking. We have also found different other kinds of problematic psychological phenomena with drivers using in-car ubicomp systems in our own user psychological experiments, reported e.g., in [30] and [31]. To solve these kinds of problems, there is a demand to understand user behavior more holistically. Most psychological dimensions of human mind and action are undoubtedly relevant in HTI research. In addition to physiological and cognitive factors, also emotional, behavioral, social and cultural aspects of the human being as a user of technology should be taken into consideration. Therefore, the question is not only of cognition, but as much of motivation, thinking, personality, trust, emotion and social interaction with other people [32]. Different research approaches are interested in different aspects of the human mind and action. Whereas traditional human factors and ergonomics research often focus on the physiological and sensory characteristics of a human, HCI

and cognitive engineering usually focus merely on the cognitive aspects. Our own approach, user psychology, can be placed between these approaches. It aims to study humantechnology interaction holistically and consider all relevant aspects of human activities and behavior. These differences mean that the type of human research applied in interaction analysis also makes a relevant criterion to discriminate paradigms and their positions in the discourse. E. Metascientific Rigour in Investigating Users Technology-oriented paradigms cannot totally neglect users; it is always necessary to design ways people could use technologies for reaching their action goals. Because of this, these paradigms normally define a set of operations people should do to reach their goals. In these paradigms the standards of human research may be thought fully intuitively in the design criteria. Traditional usability research begins with the idea that one must find uses for new technologies and carefully analyze the ways users use and should use technologies. This research normally applies user testing which usually relies on quasi-psychological methods [19]. Today, user-centered design takes one step further and uses many other methods as well to investigate users. For example, focus groups and co-design is applied to collect people’s wishes for what kind of technology they would like to use. Also, observations and marketing research have often an important role when users are investigated. However, from a metascientific point of view, even more rigorous criteria can be set for HTI research. One may demand that HTI research should be able to explain, why some design decisions are better than others. This means that the design decisions should be based on the scientific psychological principles which would be used in generating and evaluating decision solutions. This process is common in modern engineering which can use the principles of mechanics, chemistry and even nanoscience in justifying design constructs. Ideally, HTI research must also reach the normal metascientific level of engineering science. III.

APPLICATION OF THE FRAMEWORK TO THE INDIVIDUATION OF USER PSYCHOLOGY The presented framework allows us to compare paradigms in HTI from valid scientific grounds. Although some of the dimensions might be overlapping (e.g., technology-driven vs. human-driven orientation and intuitive vs. scientific practice in analyzing human), we see that they still need to be separated as own entities because of their different point of view. In the following (Table 2), we apply the proposed framework criteria in a condensed table format to two different research areas: HCI and user psychology. User psychology refers to a specific paradigm of interaction research, developed by us, which works to apply psychological concepts, methods and theories in interaction design [32, 33]. It combines the analysis of the forms of life and actions with psychological understanding of human mind and action into a holistic research and design paradigm [26, 34, 35, 32].

TABLE II. A CONDENSED COMPARISON OF HCI AND USER P SYCHOLOGY IN RELATION TO THE SUGGESTED D IMENSIONS Dimension

HCI

User Psychology

The scope of target technology

Traditionally limited to research on issues between a human and a computer, but it is not yet evident what kind of a paradigm shift will ubicomp possess on this.

Can be applied to analyze human role in any kinds of humantechnology interaction problems.

Design vs. research orientation

The goal is to improve the interactions between users and computers by designing technology which is more usable and receptive to the user's needs.

The goal is to analyze human mind and action and to base design solutions on this knowledge.

Technologydriven vs. human-driven orientation

The technology is often considered to be closed and the focus of attention is on existing technologies.

Aims to model human behavior in various environments without the constraints of existing technologies.

Intuitive vs. scientific practice in analyzing human

Usually interested on the cognitive aspects of human.

Aims to study humantechnology interaction holistically and to consider all relevant aspects of human activities and behavior.

Metascientific rigour in investigating users

Intuitive and quasipsychological testing or inquiring practices.

Testing, inquiring and explanatory practices which rely on scientific knowledge.

IV.

CONCLUSION

We have suggested a preliminary theoretical framework for analyzing the distinctions between differently labeled research approaches in the field of human-technology interaction. The framework is only one way to conceptualize the field: it may not be well suitable for analyzing the differences between certain approaches. Furthermore, the validity of the framework may well change during time as technology evolves and takes new unpredictable forms (e.g., with ubicomp systems). At the moment, the suggested framework can still provide value for people who are struggling with these concepts and debating their contents. As an example, we used the presented criteria to differentiate user psychology from traditional HCI research. Also, the criteria set ideals for how we can utilize special scientific knowledge in solving complex problems of modern HTI research. This utilization is vital because we have only two alternatives: either we use science or intuitions in developing modern information society. For centuries we have known that in the long run science is the superior alternative [11].

In any design process there are problems which must be solved before the technology is ready to be used. These solutions can be called task-necessary design solutions. These problems can often be solved without any knowledge of relevant special sciences, but it is not necessarily fair or risk-free to force technology-oriented people to solve problems which are by nature linguistic, social or psychological. We think that it is better to apply the skills of special scientists, develop their field to be better applied in solving the design problems and put aside all educated guesses. As can be seen, the presented framework is still preliminary. Future work needs to be done for example in giving formal correlations and differentiations between the paradigms of HTI research. Therefore, our aim is to continue this work in the future and develop even a more detailed framework. Finally, it can be said that the differences between the approaches in HTI research can be very slight in some cases and a new name can be coined just to put the same old wine into new trendy bottles. Nevertheless, every single one of these approaches has the same valuable goal – to help in designing technology that serves human beings in their activities. ACKNOWLEDGMENTS This work was partly supported by AMOVEO, which is a four year project (2008-2011) funded by the Academy of Finland. The work was also partly supported by Theseus, a research collaboration project on human-technology interaction funded by TEKES (Finnish Funding Agency for Technology and Innovation). REFERENCES [1]

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