User Modeling human-computer interaction

University of Paderborn
AG Computergrafik, Visualisierung & Bildverarbeitung
Prof. Dr. Gitta Domik
User Modeling
in
human-computer interaction
Seminar
Personalization
Markus Pauer
pauer@upb.de
March 10, 2004

Contents
1 Introduction 3
2 Basics 3
2.1 Human-computer interaction (HCI) . . . . . . . . . . . . . . . . . . . . . 3
2.2 The human factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.3 Information about a user . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3 UM-Shellsystems 5
3.1 Overview of UM-Shellsystems . . . . . . . . . . . . . . . . . . . . . . . . 5
3.2 The UM-Shell BGP-MS . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4 Personalized computer systems 7
4.1 The adaptive approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4.2 Adaptive computer systems . . . . . . . . . . . . . . . . . . . . . . . . . 8
4.3 A look in the future . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
5 Summary 8
References 8
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1 Introduction
Novels are the best source for new concepts in computer science, because they show us
visions for the evolution of new ways in using computer systems. A good example of
such a novel is from Arthur C. Clarke: 2001 - A space odyssey which was filmed in a
movie by Stanley Kubrick in 1968. In this movie we can see the board computer from
the spaceship ”Discovery” called HAL9000. Some of his features are the recognition of
different users and the adaption of his user interface to each individual user. I think
this shows us the potentiality in the research of the interaction of humans and computer
systems.
So what we are looking for in this paper is a way to personalize computer systems.
That means the computer system can be adapted or adapt automaticly to the needs of
each individual user. To facilitate this, we have to collect some information about the
users and develop a user model with this informations.
Before we can think about a way to personalize a computer system, we have to talk
about some basics in human-computer interaction (HCI) and user modeling (UM). In
the next section we take a look at the tools to build a model of a user with the UM-
Shellsystems. The last section is about the difficulties in the design of personalized
computer systems and the difference between adaptive and adaptable systems. At the
end there will be a short summary of what we have found out in this paper.
2 Basics
First we must talk about some basics about human-computer interaction and user modeling.
2.1 Human-computer interaction (HCI)
Let us begin with a definition of human-computer interaction:
”Human-computer interaction is a discipline concerned with the design, evaluation
and implementation of interactive computing systems for human use
and with the study of major phenomena surrounding them.” ([Per96])
As we will see the study of phenomena around the use of interactive computer systems
gets more and more important in the last few years. When we take a look at the research
in HCI we can see that there where 3 main stages in the history of research.
3 stages in HCI research In the first stage the primary intention was the design
of graphical user interfaces (GUIs) using windows, icons etc. to create more usable
systems. The next step in the research of HCI was the question, how the people use
the interfaces and components of a computer system. So that the actions not just the
interfaces were focused in this stage of research. Today we want to improve the way
people use computers to work and communicate with.
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2.2 The human factor
In the interaction of humans and computers we normally have two different views. On
the one hand we have the user with his so called ”mental model” of the computer system.
On the other hand we have the computer system with the ”user model” and its view of
the user.
Mental Model The so called ”mental model” of a user is the knowledge about the
components of a system and the experience of how to use the computer system properly
(see [CO88]).
User Model If we want an personalized computer system we need to build a ”user
model” so that the system knows the preferences, capabilities and skills of the user.
If we put this two views together, we get a system that reacts in two different ways.
The user can interact with the system and use it to perform his tasks, because of his
knowledge about the computer system. The system ”knows” the intention and goals
of the user and can adapt to the needs of him, because of the information in the user
model.
2.3 Information about a user
As we have seen, if we want a personalized computer system that adapt to the needs of a
user, we must collect some information about the user. We can divide these information
into three types (see [Kob04] and [Fis01]).
user data First we have the user data which is the information about the user himself,
e.g. his knowledge, skills and capabilities. The interesting thing with this type of
information is the intention and goal of the user when he uses a computer system.
I would like to show the importance of this information by an example. If a user selects a
new document in a word processor from a template to gererate a new letter, the system
should infer the intention and possible goals (in this case the tasks a user wants to
perform). Because normally the generation of a letter includes the lookup of an address
in a personal addressbook or a public one to fill in the destination information. Another
task is to print out the finished letter to put it in a cover and send it to its destination.
usage data The example leads us to the second type of information that must be
collected from a user – the usage data. In the example we observe the user and recognizes
that he wants to write a letter. Now we can look up his usage regularities to infer that
after he has looked up the destination address he wants to print out the document.
environment data The last type of information that can be captured is what kind of
software the user normally use, and what type of hardware is available for a user.
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3 UM-Shellsystems
”A UM-Shell is a generic domain independent system whose purpose is to
allow the development of user modeling systems.” (p. 24 in [Bla96])
3.1 Overview of UM-Shellsystems
To introduce UM-Shellsystems here is a short overview of some shell systems.
• User modeling toolkit (UMT) – Brajnik 1992
The UMT is a highly flexible and generic system to provide the development of
user models.
• General user modeling shell (GUMS) – Finin 1989
Is based on a platform-independent architecture to develop individual, long-term
user models.
• Belief, Goal, Plan Management System (BGP-MS) – Kobsa 1993
(see subsection 3.2).
• PROlog based tool for user modeling (PROTUM) – Eydner 1992
PROTUM is based on the GUMS from Finin and the BGP-MS from Kobsa.
• General user model akquisition component (GUMAC) – Kass 1988
The focus of this shell system is the akquisition of the information about a user.
• Doppelgänger – Orwant 1995
The Doppelgänger shell system was primarly build to provide a personal newspaper
to each individual user. It is a server based system, so that it stores the user model
in a distributed way.
3.2 The UM-Shell BGP-MS
The believe, goal, plan - management system (BGP-MS) is an integrated toolkit for
user modeling. It builds up a schematic user model with stereotypes and stores it in a
hierarchical partition system.
system overview As we can see in figure 1 there are four main components in the shell
system which communicate over the functional interface. The individual user model and
the stereotypes are build upon the representation system which is based on the SB-ONE
knowledge-representation tool. The user model developer can manipulate the knowledge
of the representation system with a graphical interface.
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Figure 1: internal view of the BGP-MS shell-system (from [Bla96])
KN-IPCMS The KoNstanz Inter-Process Communication Management System (KN-
IPCMS) is a platform-independent, message-oriented communication protocol which is
used to communicate between an application and the BGP-MS shell system. In figure
2 we have three types of communication.
1. If the application wants to tell the shell system about an observed believe or goal
of a user, it can send an bgp-ms-tell message to the shell.
2. The message type d-act is used to tell the shell system about an action that a
user has performed in the application.
3. Assumptions about a user are an important information for an application, so the
application can request such an assumption with a bgp-ms-ask message send to
the shell system, and the BGP-MS can send the answer in an bgp-ms-answer
message to the application.
Below the arrows we can see the messages which are described in the belief, goal, plan
language (BGPL). As we take a look at the d-act message, we can interprete it, that the
print command is executed on the user documentation. If you want more information
about other types of messages you will find it in [KP95].
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Figure 2: communication with the application
4 Personalized computer systems
In the previous section we have seen, that we can use UM-Shellsystems to develop a
user model. So the next step is to think about a way to adapt computer systems to the
needs of the users.
4.1 The adaptive approach
Because computer systems are getting more and more complex and the developer must
decide how he design the interfaces for the user at development time. He has to ... what
skills and capabilities the user have. The adaptive approach is that the system adapt to
this skills at use-time. Let us take a look at some types of adaptive computer systems.
Types of adaptive systems
• help systems
• tutorial systems
• intelligent DB-connectivity
• expert systems
• text generation
• dialog modeling
• computer games
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When it is useful to build an adaptive computer system? I think a good example is
a tutorial system that adapt to the skills of the user. It stores not only the progress of
the learning process of a participant, it recognizes the infirmities and can provide him
to handle the next chapter better than the previous ones.
4.2 Adaptive computer systems
Today we have many adaptable systems, but less adaptive systems, why? Let me list
some very relevant reasons for this.
• it is very difficult to use the knowledge about a user in an adaptive computer
system
• in an adaptable system the user decides whether or not he want to adapt something
• in an adaptive system the computer system must decide what part of the system
must be adapted to support the user
The conclusion must be that personalized computer systems should be a mixture of
adaptable and adaptive systems.
4.3 A look in the future
The demand in the research of HCI is that not the user must adapt to the computer
system that he want to use, the system adapts to the preferences and capabilities of the
user and infers the intention and goals of him. Another directive is that: ”Wherever you
are you take your preferred settings and programs with you and the computer knows
you.”. If we want a distributed, personalized computer system we need a distributed
user model which we can access over a network.
5 Summary
We have seen that we need to collect information about a user in a user model.
• information about the user in a platform-independent user model
• a distributed UM-Shellsystem
• a communication-system between the UM-Shell and the application
In the personalization of computer systems we have two main problems:
• in an adaptable computer system the user decides about the adaption
• adaptive systems must predict the intention of the user
In the future we want personalized computer systems that gently adapt to the skills and
preferences of the user and if the user want, he can adjust the system in any kind.
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References
[Bla96] Karlheinz Blank. Benutzermodellierung für adaptive interaktive Systeme: Architektur,
Methoden, Werkzeuge und Anwendungen. PhD thesis, Universität
Stuttgart, 1996.
[CO88] John M. Carrol and Judith Reitman Olson. Handbook of human-computer
interaction, chapter Mental Models in Human-Computer Interaction, pages p.
45–66. Elsevier Science Publishers, Amsterdam (Netherlands), 1988.
[Fis01] Gerhard Fischer. User modeling in human-computer interaction. User Modeling
and User-Adapted Interaction (UMUAI), Volume 11(No. 1/2):p. 65–86, 2001.
Contribution to the 10th Anniversary Issue of the Journal UMUAI.
[Kob04] Alfred Kobsa. Grundlagen der Information und Dokumentation, chapter Adaptive
Methoden - Benutzermodellierung. K. G. Saur (München), 2004.
[KP95] A. Kobsa and W. Pohl. The user modeling shell system bgp-ms. User Modeling
and User-Adapted Interaction, 4(2):p. 59–106, 1995.
[Per96] Gary Perlman, editor. Curricula for Human-Computer Interaction. 1996.
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