AN OVERVIEW OF THE RESEARCH AT

"THE EVERYDAY COMPUTING LAB" GEORGIA TECH

By

Shah Jamal Alam

A report submitted in partial fulfillment of the requirements for the CS Seminar

“Instrumented Spaces”

University of the Saarland

Summer – 2003

Acknowledgments

I would like to thank respected Prof. Wahlster, Dr. Butz and Christoph Endres

for the giving me the opportunity to participate in the seminar “Instrumented

Spaces” and present the talk. Also thanks to my seminar fellows for their

cooperation. Last but not the least; I am grateful to my family and ‘Khwarz’ for

the support and encouragement.

Abstract

We present in this report an introduction to what ‘everyday computing’ is within

the context of ubiquitous computing applications. The main objective is to

introduce to the readers the “Everyday Computing Lab” (ECL) at the Georgia

Tech, USA, its range of activities and a synopsis of its contemporary projects. We

focus on Social Net and SAORI; two research projects carried out at the ECL and

will discuss their salient features.

SJA

TABLE OF CONTENTS

Prologue............................................................................................................1 ‘Everyday Computing’ What it is all about.............................................................................................4 The Everyday Computing Lab, Georgia Tech An Introduction.................................................................................................6 Office & Communication Projects.....................................................................8 Social Implications & Home Projects...............................................................12 Social Net : An interest-matching application .....................................................15 SAORI: A system based on trust-networks.......................................................21 Epilogue..........................................................................................................25 References.......................................................................................................26

1

PROLOGUE

We are now in the era which Mark Weiser described as the third paradigm in

computing ubiquitous computing (Ubicomp) where the challenges of invisible technology

lie in the design of artifacts focused on human factors and user interfaces. What he and

other pioneers of Ubicomp had envisioned was nothing but augmented reality where

the existing technology is applied to cheap and easy-to-handle physical devices; one

person served by tiny but many computers.

Almost three centuries ago Charles Babbage dreamt of a computing machine whose

purpose was to provide both trouble-free and trust-worthy applications, serving the

human beings and facilitating them in their daily life routines. In the first half of the

twentieth century, Alan Turing who pioneered computing science, proved the

realizations of such machines would not just mean crunching numbers, but what he

envisaged was computers involved in activities that could replace humans in

performing specific if not all tasks. Computing science and the industry was fortunate,

thanks to the people from academia and the colossal advancements in the field of

information technology; Babbage’s idea has long ago became a reality.

One other visionary whose seminal article ‘As We May Think’ published in the 1905s,

was Vannevar Bush; perhaps the first to have perceived the idea of everyday

computing presenting its crux, albeit it was highly restricted given the technological

backwardness of that time. Bush gave the idea of memex which was an imaginary

mechanized device that captured an individual’s activities (both audio and visual),

maintained the bookshelf and office files and links her to the outer-world via smart

interfaces. The idea revolved around how one could achieve better techniques and

faster devices so that what was recorded could be returned quickly on demand. To

elucidate his idea, Bush presented a desk metaphor which looked as ordinary office

2

furniture but was equipped with visual interfaces for reading, a keyboard, levers and

some buttons; well-integrated to the environment. That was one of the earliest

metaphors for intelligently-designed environments.

Figure 1: Bush's Idea of everyday computing (Source Jim Gray, Microsoft Research)

Back from our detour of the historic developments, we land in the mid 1990s when

Mark Weiser at the Xerox Parc™, coined the term ‘ubiquitous computing’ and was

phenomenal in laying down its key principles. It was the dawn of ubiquitous

computing; a discipline that at present umbrella a gamut of development ranging from

miniature personal devices, digital tablets, to full-sized whiteboards. Ubicomp

addresses the challenges of designing natural interfaces, applications that are aware of

the context and easily interface with the physical and the computational environment

and lastly the acquisition live experiences and their universal accesses, something

Vannevar Bush proposed in the 1950s.

3

The following graph showed Weiser’s anticipation regarding the demand of Ubicomp

applications; though it might be too ambitious prediction, the recent growth in the

number of Ubicomp researchers worldwide and the now-available commercial devices,

makes this forecast reasonable satisfactorily.

Figure 2: Mark Weiser's prediction for the growth in Ubicomp applications’ demand

A just review of the recent advancements in the area of Ubicomp could easily take

volumes of careful research. Research in Ubicomp are presented at dozens of

conferences held every year; there are dedicated journals, special interest groups and

magazines published by world’s largest communities of computer scientists such as the

Association for Computing Machinery and the Computer Society of the IEEE etc. For

a review on recent developments, review by (Mynatt et al 2000) is recommended. We

however, would focus on a sub-discipline of Ubicomp, “everyday computing” followed by

a review to the Everyday Computing Lab at Georgia Tech in the subsequent sections.

4

EVERYDAY COMPUTING WHAT IT IS ALL ABOUT

A new dimension in Ubicomp was posit by the researchers at the Future Computing

Environments Group at the Georgia Tech very recently, ‘everyday computing’ that

emerges from considering the consequences of scaling Ubicomp applications with

respect to time; the prime motivation to build applications that support daily activities

which are inherently unstructured and informal. Time is presented as the key

parameter engulfed with providing continuous demands in a constantly present

computing environment in order to manage administering tasks, communication issues

etc, well-adaptive to varying time lags.

Horizon of ‘Everyday Computing’ research

One major issue in everyday computing is how information be represented at different

levels of human attention. The focus is on design of auxiliary interfaces operating at

different levels based on the user’s current activity or what is on the backdrop of the

user’s preferences. Evidently, design of such interfaces call for continuously available

interface that abridge the gap between the real world and virtual worlds, assimilating

into the physical environment.

Another significant challenge is providing support for ‘opportunistic behavior’ in

existing Human-Computer-Interface (HCI) designs. Since there is more than one

modus operandi in understanding our expectations from computing especially in the

day-to-day activities, everyday computing emphasizes in interrogation from users and

learning user’s requirements. This remains as an on-going effort since its inception.

5

Principles of everyday computing

Everyday computing applications are best characterized by the fact that in most cases

there is no clear-cut beginning and termination. The applications are available without

being switched on or off, working passively in a pervasive environment.

Although the tenets of everyday computing describe the activities as continuous,

expecting interrupts is fundamental. Everyday computing therefore calls modeling

interaction as a sequence of steps so that once interruption, resumption of an activity

begins from the state prior to interruption. This approach also helps in pointing out

the interruption, facilitating the user by reminding of unaccomplished tasks.

Information is acquired both visually and audio and is en masse associatively. Such

‘associative models’ are because that information stored is manipulated and

represented in different contexts depending upon the time of request. Time

henceforth plays the key role in everyday computing. As we’ve presented in this report,

the core issue is augmenting ubiquitous computing with scalability with respect to

time.

This finishes our introduction to the background relevant to the purpose of this

report.

6

THE “EVERYDAY COMPUTING LAB” GEORGIA INSITUTE OF TECHNOLOGY (USA)

Prelude of the Everyday Computing Lab

The ECL1 is one of the research units of the “Future Computing Environments”

group at the Computer Science Division of the Georgia Tech and works in

collaboration with its other units such as the “Aware Home” group etc. The current

leader of the lab, Prof. Elizabeth Mynatt was associated with the Xerox PARC prior to

her joining the lab; the opportunity of working with Mark Weiser2 for nearly three

years has greatly influenced the research projects carried out at the ECL. Currently,

there are around two dozen full-time researchers and graduate students involved in

various research projects and have contributed to quite a few publications.

Research areas and objectives

Sociological issues in as consequences to Ubicomp applications and finding new

metaphors in the domain of social interactions are the nitty-gritty of the many projects

by the ECL. Among the metaphors used are providing normal life-like environment to

ageing people by reliving their past memories, enabling the senior citizens to

communicate easily with members of family and friends.

Natural interfaces such as freeform ink, audio sensors, intelligent whiteboards, and

auxiliary displays have been designed and linked with the physical environment.

Another area of interest of the ECL researchers is providing convenient periphery for

1 ECL is the publicly used abbreviation by the Everyday Computing Lab at Georgia Tech.

2 (Late) Mark Weiser, Chief Technologist of the Xerox PARC, arguably the pioneer of ubiquitous computing.

7

sharing knowledge (at different levels of privacy) over networks. Consequently

inherent to these research directions lead to investigation in dealing with the issues of

trust, privacy and reliability of Ubicomp applications employed with the ‘everyday

computing’ perspective.

Current projects: An overview

ECL segments their projects into several categories depending mostly on the basis of

the people involved in them. We nonetheless classify their projects and research into

two broader areas of Social Involvement & Home Projects 1 and Office & Communication

Projects. The former deals with the human-human interactions in terms of interest-

matching and business applications as well as design of applications that provide

instrumented environment in homes particularly in kitchens and making health-care

and comfort available for the old. The latter, on the other hand cover projects

providing better visual aids in offices, management of activities and intelligent

scheduling systems, smart messaging etc.

1 This classification is done for the sake of clarity in presenting before the reader the basic theme of research. It’s not

endorsed by the ECL.

8

OFFICE & COMMUNICATION PROJECTS

The research projects are applications in the domain of office design, collaboration

between coworkers, and communication over the network along with inspirational

designs for presentations etc.

Below is the list of these projects (in chronological order with respect to their maiden

publications); reader may note that we are interested in the ongoing and recent

projects.

• Kimura (Hansen et al. 2001): Augmenting current office with enhanced

environment in the spirit of office of the future projects. The aim is to support

offices with passive interfaces that supplement to work areas, and provide

smooth flow of activities.

• Augur (Tullio et al. 2002): A groupware calendar system that supports

personal calendaring incorporates probabilistic models of user-attendance,

discovery of shared events and generate calendar visualizations facilitating

inter-personnel communicational.

• Instant Messaging (Voida et al. 2002): An instant-messaging client is

developed that supports visual messaging together with conventional

messaging. The prime object is to investigate the importance of context in

interaction. Best practices for incorporating context to support lightweight

communication in instant messaging are explored.

• Semi Public Displays (Huang et al. 2002): Unlike public display applications,

this project centers on displays that include focal information among members

of a group who are fairly aware of each other.

9

KIMURA: An augmented office environment

Kimura, is the ECL research project concerning with the idea of designing office of

the future closed environment. The objective is to introduce additional visual

peripherals, concordantly bifurcating user’s visual-interface into two components

namely, focal display and peripheral display. The former as the name suggest is

conventional desktop interface; nevertheless Kimura monitors and stores information

about the user’s ongoing activities, frequency of applications usages, preferences

depending upon deadlines etc. Peripheral displays are realized by montages [French män-

‘täzh: which is a composite photograph or piece of art set by combining several

separate (different) pictures or strips], which function similar to their literal meaning.

They are compositions of hypermedia providing context information via visualization

about user’s activities such as print jobs etc. Montages in an office environment are

related to each other in terms of spatial, temporal and associative linkages. For

example, visual “cards” which the user can manipulate with the most important on top

of ‘deck’; users may also add annotations to montages.

The figure below shows montages functioning in an office. On next page, the figure

illustrates Kimura in a nutshell. The system architecture comprises of desktop

monitoring, peripheral displays and interactions within the montages, monitoring of

user’s current context and using inference techniques to interpret the context.

Figure 3: Kimura integrated with desktop and variety of physical and virtual sensors. (Source: ECL)

10

AUGUR: An intelligent groupware calendaring system

The system supports personal scheduling activities but the highlight is its inherent

feature of predictive user models, discovery of shared events and novel visualizations

well-supported by interpersonal communication.

In essence the system consists of central RDBMS whereby it receives user’s calendar

data from palm devices and enhanced with the attendance likelihood based on

Bayesian inference system which alerts events scheduled together with colleagues.

Furthermore, each user possesses a copy of the network capable of learning colleagues’

attendance habits and preferences. Figure 4 on next page illustrates the system design.

The user model exploits support vector machines (SVM) models for the classification

of data which are better suited when the classification hyper plane is non-linear.

Figure 4: Block architecture of Kimura showing all components interacting. (Source: ECL)

11

Ongoing work on this project aims at defining multiple versions of the Bayesian

network due to the fact users employ different activity patterns in different scenarios.

Another improvement in progress is to develop interactive visualizations that allow

users to quickly perform training of the model for the SVM.

INSTANT MESSAGING

Besides development of a modern messaging client that supporting visual communications, the project contributes to conveying context through it. This conveying of context is supported through lightweight communication. Another significant contribution is the investigation of tension in communication which is precedent to blurring of communicative conventions, especially when it matters to persistence and synchronicity. This research proposes a design space for exploring many potential resolutions to such tensions.

Figure 5: Augur System Diagram (Source: Tullio et al. 2002)

12

SOCIAL IMPLICATIONS & HOME PROJECTS

Finding new metaphors for social interactions is the crucial area of research at the

ECL. The prime goal in designing such applications is to invent and better

comprehend an effective everyday symbiosis between humans and the emergence of

ubiquitous computing. Since social interactions and their implications depend heavily

on the large scales of time, everyday computing is the ideal channel to work through.

To broaden this spectrum, the ECL collaborates with other units of the Future

Computing Environment Group in its home projects, helping the senior citizens to

cope with the problems of ageing and providing them typical home-like environment.

The main projects in the above category are listed as,

• Digital Family Portrait (Mynatt et al. 2001): Providing qualitative

visualizations of a family member(s) daily life.

• Dude’s Magic Box and Grandma’s Lap desk (Siio et al. 2002): A novel

interaction device that supports lightweight communication between

individuals; so simple so that a grandma can easily communicate with toddler

grandchildren.

• Social Net (Terry et al. 2002): An interest matching application.

• SAORI (Goecks et al. 2002): A system based on personalized trust networks.

• Other projects are cook’s collage, dealing with mental disorder etc.

13

DIGITAL FAMILY PORTRAITS

J. K. Rowling was perhaps the first who introduced in her bestseller novel Harry Potter

and the Philosopher’s Stone (Rowling 1997) the concept of albums in which one could

see moving portraits of celebrities and others. This project however is mainly

concerned with the main fact that most adults (in United States, in particular) move to

caretaking-homes or usually limited of communication due to the age handicap.

It’s also a social problem that senior citizens are usually concerned about knowing the

well-beings and whereabouts of family members and closed friends. This project

designs ordinary -like portraits hung on the wall; however, the frames are not static,

instead equipped with lightweight devices that keep on changing frames reflecting a

kin’s daily activities. The design provides qualitative view keeping intact the privacy of

the individual portrayed. The frames keep history of events and provide visualizations

that are appropriate emotionally.

As seen in the above figure, the icons around the portrait capture health-and-

environment, emotions, and number of events in the history. Time is represented with

the band closest to the portrait as current day and the bands surrounding it average of

past (say) three activities. To reinforce the idea that time passes as one view the outer

portions of the frame, the background of each band gets progressively darker and

narrower, and the icons diminish in size.

Figure 6: Examples of Digital Family Portraits

14

DUDE’S MAGIC BOX AND GRAND MA’S LAP DESK

The crux of this project is to enable senior adults nurture their grandchildren who are

very young. The metaphor for this grandparents and their toddlers’ interaction is

realized with the home furniture. The prototype designed is a drawer which is

equipped with a lightweight processor and has halogen lamps fitted into the drawer.

Grandchildren send pictures, voices, place questions through the ‘Dude’s box’ using

touch-sensitive screen. On the other side, grandparents have ‘Lap Desk’ that receives

images, and other media. The images are annotated with voices and returned to the

young ones.

Currently, research at the ECL are aiming at design of more such prototypes and small

articles commonly found in homes and appropriate to install invisible computers.

Peek-A-Drawer is currently designed in a manner that is completely symmetrical.

Since the needs and capabilities of a grandchild are quite different than those of a

grandparent we are currently extending this prototype to accommodate these

differences.

Figure 7: Peek-a-drawer enabling cross-generational communication. (Source ECL)

15

SOCIAL NET AN INTEREST-MATCHING APPLICATION

OBJECTIVE

The sociological theories provide evidence that people have specific patterns of

collocation based on their social instincts and socio-economic circumstances. These

patterns of proximity over time are analyzed to infer potentially shared interests

without identifying those interests.

BACKGROUND

In the mid 1970s, famous sociologist Bib Latané proposed his “Theory of Social

Impact” which claimed that the two (or more) individuals influence each other, in each

other activities and share common interests. The influence is a measure primarily of

the Euclidean distance between and several other parameters. Later models by Nowak

et al. provide strong evidence of the influence of social proximity of individuals.

BASIC INFRASTRUCTURE

Before we discuss the basic mechanism of this application, we introduce the basic

architecture on which the application runs.

The design exploits P2P (Peer-to-Peer) technology as the influence of two individuals

is always a symmetric relationship. Moreover, P2P devices are cheaper, easily available

and have been reliable. What is important is that they provide natural interface for

16

representing the digital representation of the owner of the device through the physical

space ensuring anonymity. The ECL researchers describe such extension of the current

realm in P2P devices as Portable Digital Proxy (PDP) devices.

PDP are best suited in detecting peers (other individuals) in the vicinity, thus follow

the opportunistic design principle of everyday computing. Users are able to exchange

information and are able to have instantaneous interaction on detection of presence of

peers. One-to-One interaction is the central design feature of PDP applications.

The hardware used is generally consisting of a RF transceiver with the range of

approximately 10-12 feet. The researchers at the ECL used for social net, the

Cybiko™ devices.

Lovegety™: An example of PDP that did not work as expected Introduced in 1998 by Erfolg Inc® the device was advertised to be the solution for

countering the problem of embarrassment of people who want to come closer to the

opposite sex. Came in two versions for female and male, it supported “chat”,

“karaoke” features; these units would beep, and signal when a person belonging to

opposite sex is detected with similar settings of interests etc. As expected, the

machines sale reached to millions in the year of its inception.

Nevertheless, the application suffered crash as it suggested matching that resulted in

highly embarrassing situations for example senior adults matched to young teens, and

vice versa etc. Scalability was the main problem that caused the failure.

Figure 8: Lovegety™ devices; pink for female and blue for male

17

UNDERLYING PRINCIPLES OF SOCIAL NET

The idea realized by Terry et al was to exploit the previously mentioned features of

PDP devices and utilize knowledge of social networks that each person possess and

keep in focus the temporal aspects in scalability issues. Further sociological issues such

as maintaining buddy lists, and introducing trust and accountability etc were also

considered.

The above diagram shows what normally happens in our daily lives. Supposing there

are three individuals A, B and C. Initially B is a friend or acquaintance of both A and

C. Since they share common friend, it’s likely or even otherwise say, A and C

collocated with each other frequently. The always-on PDP device recognizes this

frequent interaction and later generates for B a suggestion to introduce both A and C

to each other to build a closer friendship network.

THE APPLICATION

As mentioned earlier, the Cybiko™ devices shown on next page were used by Tullio et

al. The Social Net application maintain unique identifier (ID) of the owner of the

device, list of friends or buddies of individuals acknowledged as closed, history of

encounter records. Of course, ‘brush’ encounters are not recorded. The application

works on an algorithm that uses a threshold function resulting in suggestion to

possible intimacy.

18

HOW IT WORKS

The perpetual broadcast of presence of user is always a symmetric process. This

enables to maintain integrity of user’s privacy and ensure the information exchanged is

not exploited by a single individual. When the device encounters presence of strangers,

depending upon their encounters, it maintains the timestamps and duration of

encounters in the “encounters list”. This is illustrated in the following diagram.

Figure 9: Cybiko™ devices on which Social Net was tested and demonstrated

19

ALGORITHM FOR THRESHOLD FUNCTION

The threshold function was used as intuitive and simple function. As reported in the

empirical analysis, modeling of an inverse relationship between duration of encounters

and their frequencies was the basis of the function. The idea is to capture infrequent,

but meaningful and long encounter, e.g., weekly social gatherings; also more frequent,

“bursty” encounters, e.g. at lunch, coffee-breaks etc.

The function used initially was

Where x is frequency of encounters and y, duration of encounters in (say) minutes

Pre-Conditions:

a. Minimum number of encounters must be 2.

b. Duration of encounters must be at least 10 minutes long.

Procedure: Given input of N, a set of n encounters.

1. ∀x∈N, If y ≥ 16n -1+2, Then N passes threshold function.

2. Else, (given Z some combination of n-1 encounters)

a. If ∃Z s.t. ∀z∈Z, , y ≥ 16(n-1) -1+2, Then Z passes test.

b. Else n ß n-1

i. Decrement n

ii. If n = 1, test fails; return.

iii. Else, repeat Procedure.

2,216 1 ≥+≥ − xxy

20

WHEN TO SUGGEST AN INTRODUCTION

Following meeting the threshold function’s criteria, the basic expectation is that the

IDs of strangers of which the criteria are fulfilled are likely to share common interests

with the owner of the application.

Subsequently, the list of unknown IDs is passed to those in the friends list of the user

and the Friend’s device matches the passed list with her friends’ list. On fetching of

names that match, the now mutual friend is suggested by the application to introduce

the two. This friend is the “Human in the loop”.

MEASURES OF PROXIMITY

The researchers define three dimensions of proximity namely spatial, temporal and

social proximity over the network. The first focuses on how people collocate and

exploits necessities for people to remain physically near. Spatial proximity assumes that

activities and interests are shared when the set of encounters pass the test. Temporal

proximity measures patterns of interactions over time especially the time of encounter

such as when was the encounter e.g. time of day, day of week, etc.

Social proximity is in its crux based on the concept of “human in the loop” the mutual

friend. The human provides the social filter as studies have shown that People decide

better if introduction of two individuals is appropriate and determine best way of get-

together. This measure reduces number of potential introductions by requiring mutual

friend. The social filter implicitly introduces elements of trust and accountability.

21

SAORI PRIVACY MANAGEMENT IN SOCIAL CONTEXT

INTRODUCTION

SAORI is a research project that is now integrated with several other Ubicomp

applications and has been reported by the researchers to solve many issues regarding

accountability, trust and reputation in everyday computing.

The motivation behind the project is given by the following quote from Goecks et al.

“…protecting one's privacy is not so much about what information is shared but

about who that information is shared with and when it is shared”.

The system defines Trust-Networks: based on individual’s social network and build upon

them Personalized Reputation System.

We first define the notion of reputation and prior to it what trust is.

Trust: An individual’s trust is the degree of belief that, for a particular situation, an

entity (an individual or a system) has the capacity to harm the individual but is not

expected to exercise this capacity.

Reputation: An entity’s reputation is some notion or report of its propensity to fulfill

the trust placed in it (during a particular situation); its reputation is created through

feedback from individuals who have previously interacted with the entity.

22

TRUST NETWORKS

Trust networks are social networks that constitute of an interconnected structure of a

person’s relationship within a community with the individual as the focal node. The

following figure explains pictorially this idea.

Need for such networks arise in online reputation systems such as BBB™, eBay™ etc.,

where a user interested in doing business or buying something online, has to trust on

the feedback of hundreds and sometimes thousands of individuals who are unknown

to the user. From the sociological point of view, people give more weight age to the

advice of those who are near to them socially; these kinds of advices are known in the

jargon of sociology as “word-of-mouth”. Interestingly, this leads to a paradoxical

situation in which ‘word-of-mouth’ are highly values yet they often have very few data

points; on the contrary reputation systems have large data points as samples but are

quite a less reliable.

Researchers at the ECL resolve this by building personalized reputation systems over

the trust-networks, which we discuss next.

Figure 10: A simple personalized trust-network (Source: Geocks et al.,2002)

23

PERSONALIZED REPUTATION SYSTEMS (PRS)

We defined what is meant by reputation, now the underlying principle is given by

Geocks et al as:

“People usually not value reputation-systems (which rely on thousands of users’

feedback) as they are unable to asses the trustworthiness of the others. Design of a

personalized is therefore called for.”

The personalized reputation system developed at the ECL weighs an entity’s

reputation based on the user’s trust-network. Essentially, the working is similar word-

of-mouth reputation.

The authors report the following simple scenario that explains the system well:

Consider a simple, qualitative example. Imagine that a user trusts person A and person B, but doesn’t know nor trust person C or person D. Now assume that all four individuals have provided feedback about an entity; persons A and B provided positive feedback, but persons C and D provided negative feedback. In a normal reputation system, the entity’s reputation would be neutral and the user wouldn’t be able to determine whether to trust the entity. However, a PRS would generate a positive reputation for the entity by weighing the feedback of persons A and B more heavily than the feedback of persons C and D. In the next section we discuss a system that enables users to manage their personal information in a Ubicomp environment using trust networks and a PRS.

Currently, the PRS is integrated with Augur which is introduced in the precedent pages

of the report.

24

MANAGING PRIVACY

To provide privacy in the PRS, data for PRS is taken from Augur to build the user’s

trust-network. The theme is to build the PRS of user when an individual requests the

user’s information or an advice in a business environment. This network gets

connected to each individual on the user’s trust list which then connects the individual

to those on the individual’s trust-list for each individual on the user’s network.

To map the ‘degree of trust’ to user’s to the type of information user shares with

colleagues in Augur, the authors proposed the following layers of trust the user can

have in a corporate environment.

Degree of trust Shared Personal Information

Very much E.g. Calendar events and

likelihood of a person to attend

an event.

Somewhat Calendar events only

Little Availability

Distrust (Not at all) None

Once the PRS is built, the system performs network analysis to infer an individual’s

reputation.

25

EPILOGUE

Social concerns such as privacy, trust, reputation are pivotal in design of everyday

computing systems. Another issue is scalability in which applications such as those

dedicated for interest-matching breakdown when every individual has a device in their

hand in a closed space. In case of social net, the authors have reported that the

threshold function showed adequate during experiments. One design flaw that was

observed later was two persons introduced not always add each other as friends

Moreover tests revealed users’ concern over physical tracking; however, decentralized

design relieved users from tracking-fear. For PRS, rules-of-the-game is still in progress

and more realistic models call for. One advantage the PRS does provide is the

flexibility for users to maintain their privacy policy.

26

REFERENCES

“Bleep at First Sight”. Wired News, May 15, 1998.

Abwod, G.D., Mynatt, E. D. “Charting Past, Present, and Future Research in

Ubiquitous Computing” ACM Transactions on Computer-Human Interaction,

Vol. 7 No. 1 (29-58), Mar. 2000, ACM Press.

Bush, V. “As We May Think”, The Atlantic Monthly, July 1945.

Goekcs, J., Mynatt, E. D. “Enabling Privacy Management in Ubiquitous Computing

Environments through Trust and Reputation Systems”, Proc. CSCW’02, New Orleans,

USA, 2002.

Gray, J. “What Next? A Few Remaining Problems in Information Technology”,

Turing Award Lecture, 1998, ACM Press.

Feigenbaum, E. A. “How the What Becomes How”—Turing Award Lecture, CACM,

39(5), 1996, ACM Press.

Hansen, K.M., MacIntyre, B., Mynatt, E.D., Tullio, J., and Voida, S. “Hypermedia in

the kimura system: Using spatial, temporal, and navigational relationships to support

multitasking and background awareness”, Proc ACM Conference on Hypertext and

Hypermedia, Aarhus, 2001, ACM Press.

Hodges, A. “Alan Turing: The Enigma”, Vintage, 1992.

Huang, E. M., Mynatt, E. D., "Semi-public displays for small, co-located groups.” Proc

ACM CHI, Fort Lauderdale, 2002, ACM Press.

27

Mynatt, E. D., Rowan, J., Craighill, S., Jacobs, A. “Digital Family Portraits: Providing

peace of mind for extended family members”, Proc. ACM Conference on Human

Factors in Computing System, Seattle, 2001, ACM Press.

Terry, M., Mynatt, E.D., Ryall, K., Leigh, D. “Social Net: Using Patterns of Proximity

Over Time to Infer Shared Interest.”, Proc. ACM SIGCHI, 2002, ACM Press.

Tullio, J., Mynatt, E., Nguyen, D. “Augmenting shared personal calendars.”, Proc.

ACM Symposium on User Interfaces Software and Technology, Paris,

Nov. 2002, ACM Press.

Voida, A., Newstetter, W.C., Mynatt, E.D., “When conventions collide: The tensions

of instant messaging attributed ”, Proc ACM CHI, 2002.

Voida, S., Mynatt, E.D., Corso, G. M. “Integrating Virtual and Physical Context to

Support Knowledge Workers”, IEEE Pervasive Computing, Vol1. No. 3, 2002, IEEE

Press.

Weiser, M. “The Computer for the 21st Century”, Scientific American, Sept. 1991.

Weiser, M. “Building Invisible Interfaces”, Proc. ACM Symposium on User Interfaces

Software and Technology, Nov. 1994, ACM Press.