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Serendipity within a Ubiquitous Computing Environment: A Case for Opportunistic Browsing Oscar de Bruijn and Robert Spence Imperial College, Dept. of Electrical and Electronic Engineering, Exhibition Road, London, SW7 2BT, United Kingdom {o.debruijn,r.spence}@ic.ac.uk

Abstract. We investigate an important interaction that can take place in a ubiquitous computing environment, that of opportunistic browsing, a form of information gathering on the fly. Opportunistic browsing is characterised by being ubiquitous, unintentional and effortless. In this paper, we clarify the concept of opportunistic browsing and place it within a cognitive framework. We further discuss the nature of the interactions that can be triggered by the serendipitous discovery of information through opportunistic browsing and the importance of context-awareness, and we identify important research issues.

1

Introduction

You are having a coffee and a chat with some friends, when, suddenly, your eye catches some of the information that comes flowing by on the screen that is forms part of the table at which you are sitting (see Figure 1). It is an article about the Science Fair and you wonder if this may lead you to find information about the local astronomers club. With your finger you drag the item into the middle of the table where more detail becomes visible. After reading the text you see that the article does mention the astronomers’ club, but it does not include a contact address or a hyperlink. You proceed to drag the article onto the icon representing the coffee table Agent, hoping that the information subsequently retrieved by the Agent will include the home page of the astronomers club. After some time has elapsed, during which you talked about the film you saw last night, you notice that the logo of the astronomers club comes flowing by and when you view their Web page in the middle of the table you see that it contains all the information you need to contact them. You do not want to interrupt the conversation with your friends any longer, so you simply store a link to the page on the token on your key ring so you can have a closer look at home. This example illustrates peoples’ constant need for information, even when this information is not actively pursued. The reason for not actively pursuing relevant information immediately may be that it is not clear how this information can be obtained or that the effort involved in its pursuit is perceived as being too great. Sometimes one might not even realize that the information is relevant until it is G. D. Abowd, B. Brumitt, S. A. N. Shafer (Eds.): Ubicomp 2001, LNCS 2201, pp. 362-369, 2001.  Springer-Verlag Berlin Heidelberg 2001

Serendipity within a Ubiquitous Computing Environment

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encountered. One of the aims of this paper is to describe such serendipitous behaviour more formally and establish a framework for the development of interactive applications that support it within a ubiquitous computing environment. We argue that the realisation of ubiquitous computing environments offers unique opportunities for injecting serendipity into human-computer interactions. Especially since human beings have many interests that can be satisfied by exposure to appropriate items of information, but cannot continuously, simultaneously and consciously articulate all those interests, we should enable people to discover relevant information without requiring them to actively search for it. We now examine this kind of behaviour in more detail, place it within an appropriate cognitive model and suggest suitable interaction mechanisms. a

b

Fig. 1. (a) The coffee table supporting opportunistic browsing. (b) A close-up view of the display, showing information items that move slowly around the perimeter

2

Opportunistic Browsing

In this paper we are concerned with one particular form of browsing, one that makes opportunistic use of information we encounter as part of our everyday activities even when no conscious information seeking is intended. It is for this reason that we speak of “opportunistic browsing”. We can define opportunistic browsing (henceforth referred to as OB) as the continuous but largely unconscious monitoring and filtering of information with the potential to trigger more purposeful behaviour. The defining characteristics of OB, setting it apart from other forms of browsing, are ubiquity, being unintentional, and requiring no cognitive effort. Opportunistic browsing is ubiquitous because it is a process of information filtering that occurs all the time and everywhere, while talking to friends or driving to work. It is unintentional because people are not consciously looking for information, and it requires no cognitive effort because OB is an automatic process that is part of peoples’ normal pattern of information processing.

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Oscar de Bruijn and Robert Spence

It has often been stated that the growing amounts of information we are exposed to at every moment could increasingly lead to “information overload”. However, we argue that it is not the amount of information per se that creates a problem. In fact, the human information processing system is uniquely equipped to cope with large amounts of information by selectively attending to potentially relevant information and ignoring irrelevant information.1 This ability has been demonstrated repeatedly, although arguably its most well known manifestation is the “cocktail party effect” [5]. The cocktail party effect describes how a listener is able to selectively attend to the single voice that says something of interest to the listener (e.g., their name) while many different voices are audible in a room. In the next section we present a model of the kinds of cognitive activity involved in opportunistic browsing built around a theoretical construct developed by Potter [12, 13] called Conceptual Short Term Memory (CSTM). 2.1

A Cognitive Model of OB

The process of opportunistic browsing is summarised in Figure 2. It starts with the perceptual registration of content, which may be seen or heard. Each item of meaningful content (e.g., objects, phrases and scenes) results in the rapid activation of corresponding conceptual representations in CSTM.2 These representations are, however, equally rapidly forgotten if they are not selected for retention in a more permanent form of memory (i.e., working memory). Potter [13] remarks that “The idea is that most cognitive processing occurs on the fly, without review of material in standard short-term memory and with little or no conscious reasoning. Yet, these rapid processes are flexible, not fixed: new sentences are processed, new scenes are comprehended, important items are selected for attention even though they cannot be explicitly anticipated …” (p. 14). This model attributes four important characteristics to OB that result from the role of CSTM in the processing of information that we encounter in our everyday environment: (1) encountered information rapidly (within about 100ms) activates meaningful representations, (2) activation of these representations leads to the retrieval of additional relevant information from long-term memory (LTM), (3) the information retrieved from LTM may be associated with a previously unsuccessful or prematurely aborted attempt to find similar information, which may cause our attention to be drawn and an appropriate action to be initiated, and (4) the whole process up to the point where our attention is drawn to relevant information occurs with little or no conscious effort since any information that does not draw our attention is quickly forgotten.

1

Information overload becomes a problem only when there is too much relevant information. For example, when someone has to attend to two or more sources of information and combine these in order to accomplish a task. 2 A number of models of visual information processing assume stages in that process that serve a similar purpose to CSTM (e.g., [1], [7]).


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Fig. 2. A model of opportunistic browsing. Perceived information activates representations in CSTM. Association with information from long-term memory triggers a purposeful action (see text for explanation)

2.2

Browsing Typologies

Several other forms of browsing have been proposed, including forms that are similar to opportunistic browsing. Wilson [17] identifies four kinds of browsing: passive attention, passive search, active search, and ongoing search. The difference between the first two and the latter two types of browsing is the intention behind the activity. Passive attention, for example, operates while watching television or listening to the radio, where information acquisition may take place without intentional seeking. Passive search operates when search for one kind of information (or other behaviour) results in the acquisition of another kind of information that happens to be relevant. We consider both passive attention and passive search to be forms of OB in that no information seeking is intended but useful information is nevertheless acquired. In fact, we see no fundamental difference between passive attention and passive search; watching television and searching for information (other than the information acquired by OB) are just the kinds of behaviour during which OB takes place. In contrast, active search and ongoing search both involve active acquisition of information relevant to the goal of the search. Other classifications of browsing behaviour were proposed by [10] and [4], but neither of these include forms of browsing that could be considered opportunistic. In the next section we argue that a ubiquitous computing environment can be suitably configured such that it provides an optimal environment for making serendipitous discoveries through opportunistic browsing and supports the interactions triggered by these discoveries.

3

Ubiquitous Computing

According to [15], a ubiquitous computing environment is characterised by the disappearance of the computers within it, in the sense that they have vanished into the background. Additionally, it is usefully characterised by the dictionary definition of ubiquitous (“being or seeming to be everywhere at the same time”), in the sense that the layperson need not consciously go to the computer. The computer lies behind

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familiar artefacts such as the coffee table, the bus stop and the information display in the shopping mall, as well as the home information terminal. 3.1

Enhancement of Serendipitous Information Retrieval

One of the most exciting opportunities created by ubiquitous computing is the possibility of enhancing serendipitous information retrieval by increasing the amount of information that is presented to a user. Relevant techniques are already appearing: the familiar scrolling news-bars (a la Times Square), the sequenced advertisement, and continuously scrolling text information such as news headlines or stock prices on the desktop display (e.g., [20], [19], [6], [8]) or television (e.g., CNN). Realisation of a ubiquitous computing environment also opens the possibility for ambient presentation of information in the periphery of people’s attention [16][18]. In the context of the Living Memory project we have explored the enhancement of serendipitous information retrieval by embedding information displays in familiar artefacts such as coffee tables (Figure 1), bus stops, floors, park benches, and shopping trolleys (e.g., [9]). Although the concept of an information fire-hose may possess worrying connotations, and must be managed with maturity, its implication of a plentiful supply of information widely available is to be preferred over some existing and developing paradigms that are either intrusive or rely on personalisation. Personalisation, for example, can severely limit the number of opportunities for serendipitous discovery. In the example of a personalised newspaper (the “Daily Me”), users would have no opportunity to read news items they might find interesting but which do not fit into the range of topics present in their personal profile. 3.2

Situated Interactions

It is reasonable to assume that the behaviour triggered by OB depends on the extent to which people can interact with the medium in which the information is presented, and hence we refer to any such behaviour as situated interaction. Suchman [14] introduced the term “situated action” to underscore “the view that every course of action depends in essential ways upon its material and social circumstances” (p. 50). Similarly, situated interaction depends on its material, in terms of both the information and the affordances offered by the medium in which this information is presented, and the social circumstances in terms of the location of the display and the activity the observer is engaged in. Thus, information presented on a display embedded in a coffee table triggers a different kind of interaction than information presented on a large screen display in the mall, since these represent different media and occur in different contexts. It is important that the interactions that are being triggered by the serendipitous discovery of useful information through OB do not cause too much disruption of ongoing activities. Such disruption may first of all be socially undesirable in certain situations, and it could also lead to an unacceptable increase in users’ short-term memory load if they have to keep track of several ongoing activities in parallel.


3.3

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Content Selection

It may appear contradictory that in order to increase the opportunities for serendipitous discovery through opportunistic browsing, some sort of selection of information is probably required. As we pointed out in section 3.1, content selection based on personal interest profiles could seriously diminish the potential for serendipitous discovery. However, we suggest that content is selected according to the context in which an information artefact is situated instead. The need for contextawareness has often been argued in relation to mobile handheld and wearable computing devices (e.g., [11]), but context-awareness may be an equally important characteristic of stationary devices that are part of a ubiquitous computing environment. For example, content could be selected according to its relevance to the location of the display. For the same reasons that apply to mobile applications, certain information may become more or less important depending upon where the user is located [5]. Selection by location could lead to the same restricted information exposure as personalisation but for the fact that users’ movement through the environment is likely to take them through many different locations, ensuring their exposure to a wide variety of information. Ultimately, artefacts might be made aware of what is going on in the local community, allowing them to respond to local events and occasions [2].

4

Conclusions

One thing technology has failed to give us more of is time, and it would therefore be advantageous if we could use our time more efficiently by combining everyday activities with the search for information? This can be achieved when the environment is infused with information that can be retrieved through opportunistic browsing. In this paper we have defined a model for opportunistic browsing and argued that the human information processing system is uniquely equipped to make opportunistic use of information. We have also described some of the characteristics of the interactions that can be triggered by the serendipitous discovery of information through opportunistic browsing and discussed some important issues that need to be considered when developing new artefacts to support OB in a ubiquitous computing environment. Many issues remain, however, opening many avenues for further research. Considerable effort will be devoted to innovation leading to new artefacts supporting opportunistic browsing, new information presentation techniques, new interaction modes and new information scenarios. To assess and guide advances in opportunistic browsing, an extensive programme of research is required that combines laboratory studies and the evaluation of both prototypes and in-situ applications. Finally, much will be gained through ethnographic studies of new artefacts and systems as they are developed, additionally feeding back into the innovation and development process.

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Acknowledgements The research reported in this paper was funded by the European Community (Living Memory / ESPRIT / I3 / 25621). We would like to thank the members of the Living Memory team for useful discussions and Philips Design for supplying the pictures of the coffee table.

References 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.

12. 13. 14. 15. 16. 17. 18.

Anderson, J.R.: Rules of the Mind. LEA, Hillsdale (1993) de Bruijn, O., Purcell, P.A., Spence, R., Stathis, K.: Agent-Based Interaction Design for Connected Communities. Manuscript in preparation (2001) Cherry, E.C.: Some Experiments on the Recognition of Speech, with One and Two Ears. J. of the Ac. Soc. of Am. 25 (1953) 975-979 Choo, C.W., Detlor, B., Turnbull, D.: Information Seeking in the Web: An Integrated Model of Browsing and Searching. FirstMonday 5 (2000) http://firstmonday.org/issues/issue5_2/choo/index.html Davenport, E., Whyte, A., Barr, K., Buckner, K.: LiMe Deliverable 2.3 Taxonomies of Tools, Community Content and Narratives (1998) Desktop News: http://www.desktopnews.com/ Ericsson, K.A., Kintsch, W.: Long-term Working Memory. Psych. Rev. 102 (1995) 211-245 Jotter 2000: http://www.jotter.com/ Living Memory: http://www.living-memory.org/ Marchionini, G.M.: Information Seeking in Electronic Environments. Cambridge University Press, Cambridge, UK (1995) Pascoe, J., Ryan, N., Morse, D.: Issues in Developing Context-Aware Computing. In: Gellersen, H-W. (ed.): Proc. of the First Int. Symp. HUC’99. Lecture Notes in Computer Science, Vol. 1707. Springer-Verlag, Berlin Heidelberg New York (1999) 208-221 Potter, M.C.: Very Short-term Conceptual Memory. Mem. & Cog. 21 (1993) 156-161 Potter, M.C.: Understanding Sentences and Scenes: The Role of Conceptual Short-Term Memory. In: Coltheart, V. (ed.): Fleeting Memories: Cognition of Brief Visual Stimuli. The MIT Press, Cambridge, MA. (1999) Suchman, L.A.: Plans and Situated Actions. The Problem of Human Machine Interaction. Cambridge University Press, Cambridge (1987) Weiser, M.: The Computer for the Twenty-First Century. Scientific American, September (1991) Weiser, M., Brown, J.S.: The Coming of Age of Calm Technology. http://nano.xerox.com/hypertext/weiser/acmfuture2endnote.htm Wilson, T. D.: Information behaviour: An interdisciplinary perspective. Info. Process. & Manage. 33 (1997) 551-572 Wisneski, C., Ishii, H., Dahley, A., Gorbet, M., Brave, S., Ullmer, B., Yarin, P.: Ambient Displays: Turning Architectural Space into an Interface between People


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and Digital Information. In: Norbert A. Strietz, Shin’ichi Konomi, Heinz-Jürgen Burkhardt (eds.): Cooperative Buildings, Proc. of the First Int. Workshop, CoBuild’98. Lecture Notes in Computer Science, Vol. 1370. Springer-Verlag, Berlin Heidelberg New York (1998) 22-32 19. WorldFlash, http://www.worldflash.com/ 20. Yahoo, http://sg.news.yahoo.com/