1 Designing for Usability – Domain Specific Human-Computer Interfaces in Working Life. JAN GULLIKSEN Abstract Despite the tremendous development and increasing availability of computers in work- ing life, severe usability problems are frequently observed, leading to bad user acceptan- ce, negative stress, anxiety, and even health problems for the users. We need to create a scientific foundation for the studies of humans interacting with computer systems to achieve a specific work task in a physical and psycho-social work environment. Interdis- ciplinary studies of systems analysis, software engineering, cognitive and perceptual psychology, sociology, organisation theory, human factors, and design and art, a l l contribute to the science of human-computer interaction (HCI). With an engineering approach to design, scientific principles, technical information and imagination can be used in the definition of a mechanical structure, machine or system to perform pre- specified functions with maximum economy and efficiency. This thesis covers methods for the study and modelling of a human-computer system, focusing on many relevant aspects: Development of organisations, work activities, in- formation technology and humans and their competence. The importance of domain knowledge in an iterative user centred development process is emphasised. Analysis of information utilisation is presented as a method for capturing how information entities are being used in the work process, to support directly design controlling knowledge. A workspace and document-oriented approach to interface design for skilled professionals is described to prevent the problems occurring with design of graphical user interfaces. Creativity supporting design methodologies are described as means for being able to develop efficient and effective user interfaces, based on the results of the analysis of information utilisation. The concept of domain specific design for the establishment of a higher-level style guide for domain knowledge acqui- sition is introduced as a design controlling methodological support in the user interface development process. Case handling work activities have been particularly studied, applying the domain specific approach on the health care and tax handling domains. A general framework for case handling work activities has been specified, which supports work related judgement and decision making. The overall goal is to make computer support in working life easy, efficient and pleasant to use. Through this development, computer support can be enhanced by making it more cost efficient and less time consuming. Developers and designers can produce a result that fulfils the users’ objectives and requirements in accordance with the achievements of specific tasks.
Transcript
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Designing for Usability –Domain Specific Human-Computer Interfaces
in Working Life.
JAN GULLIKSEN
Abstract
Despite the tremendous development and increasing availability of computers in work-ing life, severe usability problems are frequently observed, leading to bad user acceptan-ce, negative stress, anxiety, and even health problems for the users. We need to create ascientific foundation for the studies of humans interacting with computer systems toachieve a specific work task in a physical and psycho-social work environment. Interdis-ciplinary studies of systems analysis, software engineering, cognitive and perceptualpsychology, sociology, organisation theory, human factors, and design and art, a l lcontribute to the science of human-computer interaction (HCI). With an engineeringapproach to design, scientific principles, technical information and imagination canbe used in the definition of a mechanical structure, machine or system to perform pre-specified functions with maximum economy and efficiency.
This thesis covers methods for the study and modelling of a human-computer system,focusing on many relevant aspects: Development of organisations, work activities, in-formation technology and humans and their competence. The importance of domainknowledge in an iterative user centred development process is emphasised. Analysis o finformation utilisation is presented as a method for capturing how informationentities are being used in the work process, to support directly design controllingknowledge. A workspace and document-oriented approach to interface design forskilled professionals is described to prevent the problems occurring with design o fgraphical user interfaces. Creativity supporting design methodologies are described asmeans for being able to develop efficient and effective user interfaces, based on theresults of the analysis of information utilisation. The concept of domain specificdesign for the establishment of a higher-level style guide for domain knowledge acqui-sition is introduced as a design controlling methodological support in the userinterface development process. Case handling work activities have been particularlystudied, applying the domain specific approach on the health care and tax handlingdomains. A general framework for case handling work activities has been specified,which supports work related judgement and decision making. The overall goal is tomake computer support in working life easy, efficient and pleasant to use. Through thisdevelopment, computer support can be enhanced by making it more cost efficient andless time consuming. Developers and designers can produce a result that fulfils theusers’ objectives and requirements in accordance with the achievements of specific tasks.
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Designing for Usability –Domain Specific Human-Computer Interfaces
in Working Life.
JAN GULLIKSEN
”Concern about the human being and his/her destiny must always be the main inte-rest in every technical development effort... never forget that, amongst your dia-grams and equations.”
Albert Einsteinin ”Science and Values”
”The natural scientist and the humanistneed to be Siamese twins.”
Tage Danielssonin ”Den akterseglade humanisten”
INTRODUCTION
Computerisation and the use of computer based information systems have increased tre-mendously during the last three decades. Today, almost every existing work situationmore or less relies upon the computer support. The efficiency of the work, the qualityof the produced outcome, and the satisfaction of the user performing the work is direct-ly related to, amongst other things, the computer support. In administrative, routinework, such as case handling, which is the main focus of these studies, the purpose of thework is never to operate the computer. The computer is merely a tool that has to be usedas an aid to help achieve the main purpose of the work, i.e. to perform case handling; tobe appreciated. Far too often in real life you come across situations as a customer whereyou are approached in a non-service manner, resulting in anger and frustration. And al-most as often this lack of service is excused by a non-functioning computer support. Re-gardless of whether this problem is to be related to a lack in competence or knowledgeby the clerk performing the case handling, or if it can be related to poor effectiveness orfunctionality by the computer support, it is a substantial problem that needs to be solved.A careful and dedicated design of the computer support and the work environmentshould help the clerk performing the work to achieve the goals and, thereby, also incre-asing the customer satisfaction. The results and methods presented in this thesis w i l lhopefully constitute a step in the complex process of achieving more usable and usefulcomputer support in working life in the future.
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GOALS AND PURPOSES
This thesis aims at identifying factors and providing additional methodological toolsfor more efficient and effective analysis, design and construction of human-computerinteraction in working life. The idea is that by creating better user interfaces to infor-mation systems, the efficiency of work will increase, the work environment will bemore enjoyable and pleasurable to interact with, and, at the same time, the developmenttimes and costs will decrease. This research work has been applied to various workactivities, such as tax case handling, health care, and bank and insurance work, topromote its general applicability. Central theoretical aspects that have been stressed are:the need for structured methodological aids for design; the analysis of how informationis used in a specific work situation; and the domain studies and the case handlingdomain specific design guidelines. The concept of domain specific design, usingdomain specific style guides, is also introduced to create a higher-level platform foruser interface design within a specific application area. Case handling work activitiesin general have been studied as examples of a broad range of administrative routinework activities performed by skilled professionals.
SYSTEMS ANALYSIS
This work is a doctoral dissertation in systems analysis. Systems analysis is the study o fcomplex systems by modelling relevant aspects of the reality and performing experi-ments on those models in order to predict the effects on the real system [Gustafsson,Lanshammar, & Sandblad, 1982]. A model is an abstraction of relevant aspects of asystem fulfilling some special purpose. One of the reasons for studying the reality withthe help of systems analysis is the problems, or even impossibilities, of predicting thebest, or even a good, behaviour from systems that have not yet been constructed.
In this research, the human being, interacting with the computer in a specific physi-cal and social work environment, to achieve a certain task, is the system under study. Westudy this physical system by analysing it according to several different methodologiesand by constructing models to describe some aspects of it. The models help to specifymethods and develop tools to enhance design, construction and maintenance of computersystems. Also, aspects relevant for the improvement of other parts of the system than thecomputer can be traced in this way. Important aspects in this research work, incorporatedfrom the theories of systems analysis, are the importance of restricting the systemdomain and to be aware of the effects these restrictions can have. Further, the notion o fthe subjectivity in modelling is important in order to explain diverging behaviour. Asignificant method in systems analysis is the method of simulation, i.e. the analysis o fmodel behaviour by model experiments.
INTERDISCIPLINARY STUDIES
One basis for studying the complex system of a human achieving a task in a computer-based work environment is the need for an interdisciplinary approach. The followingdisciplines have substantial contributions:
1) Software Engineering and Computer Science2) Human Factors and Work Activity Analysis
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3) Cognitive Psychology including Perception4) Sociology, Linguistics and other Human Sciences5) Design and the Science of Art
The assembled knowledge about computers, the architecture, the software and thefunctionality can be entirely understood by a human being, in that it is a purely techni-cal system created by humans. The other side of the human-computer system, the humanbeing, is not as easy to understand. Still, today the assembled knowledge on the humancognitive and perceptual functionality is not enough for the consequences of a compu-terisation of a work task to be fully understood. The study of cognitive, perceptual andsocial psychology is, nevertheless, important and there are some findings that we regardas directly applicable in the process of designing human-computer interfaces. Manydifferent models and theories for explaining and predicting human features exist. Ourknowledge is too limited to be able to falsify these models. We are satisfied with anexplanation of human behaviour and information processing that can help us fulfil theoverall goal of improving the human-computer work situation.
Cognitive Psychology is the study of how human beings take in, represent, treat and useinformation. Central in this process is the organisation and structure of the humanmemory. According to the Stage Theory [e.g., Gleitman, 1991] of human cognitive capa-city, human memory can be divided into short-term memory (STM) and long-termmemory (LTM). Together STM and LTM form the nucleus of the information-pro-cessing system. LTM has no known capacity limits and some research even indicates thatthere is no memory loss; LTM represents information on a permanent basis. Memoryretrieval can be ”distorted” (e.g., because of interfering retrieval cues to memory units).Another limitation is, however, more important for HCI. The STM, on the other hand,has a limited capacity (7±2 units) but it is possible to group units into larger ”chunks”that occupy less memory. If something new is entered older ”memories” are suppressedto leave space for the new memory units. Information is lost from the STM after about12-15 seconds, if the information is not further worked upon. To be able to enter infor-mation into the LTM, the information needs to be more deeply encoded to be successiv-ely transferred from STM to LTM. In human interaction with a computer the load onSTM could be decreased by enhancing the possibilities for the computer user to createlarger, work-related memory chunks and to relieve the user from needing the STM todeal with controlling and manoeuvring the computer. Lind [1991] showed that utilis-ing the STM as a temporary storage for information sets presented on sequential com-puter screens demand large cognitive load by the user compared with simultaneous pre-sentation. Cognitive load caused by the information system (e.g., by overloading theSTM) can be a severe factor when judging the comfort and efficiency of a work situa-tion [Nygren, Johnson, Lind & Sandblad, 1992]. It can cause negative stress, anxiety,frustration, and even health problems [Johnson & Johansson, 1991].
Perception is a subset of cognitive psychology and incorporates the interpretation o fsensations (that is, immediate and basic experiences generated by isolated simple stimu-li), giving them meaning and organisation [Matlin & Foley, 1992]. By using existingknowledge on the human perceptual capabilities, considerations relevant for the visualperception and recognition of information patterns can be derived. For exampleGestalt Psychology states that groups of stimuli acquire a pattern quality which is morethan the sum of their parts [Gordon, 1989]. In relation to human-computer interaction,this means that the design of user interfaces should aim at creating meaningful infor-mation patterns. Gestalt Psychology can be used to help us understand the effects o fgrouping information that belong together, using consistent coding of colours, fontsand sizes, and separating figure background of different levels of user interface objects.
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A central tool to aid the understanding of user interface design and for deriving pre-requisites for the design process is the construction and use of models of human-compu-ter systems [Rasmussen, 1986]. These models aim at understanding why people undertakecertain performance patterns and how they can be improved in carrying out a specificwork task with computer support. One model that has had a great impact on human-computer interaction is the skill-rule-knowledge framework corresponding to diffe-rent levels of familiarity with a task or environment [Rasmussen, 1983]. At a skill-basedlevel of human performance, individuals behave according to stored patterns of pre-programmed actions. The rule-based level applies to the tackling of familiar problemsby the application of stored conditional rules. In novel situations, the knowledge basedlevel is used for on-line planning, using conscious analytic processes and stored know-ledge to acquire expertise. Rasmussen further elaborates this within research on humanerror. He identifies eight stages of decision making (activation, observation, identi-fication, interpretation, evaluation, goal selection, procedure selection and activation)with possible short-cuts, explaining stereotypical reactions and associative leaps toovercome the laborious and slow knowledge-based processing. The generic errormodelling system (GEMS) further elaborates this by introducing the dynamics of humanerror and tendencies to treat problems on inappropriate levels [Reason, 1990].
A different view on human information processing divides the problem solvingcapabilities based on (at least two) levels of awareness. On a high conscious level, the hu-man being is single processing; that is, only one such process can be performed at a time.For example, solving mathematical problems, reading, making judgements or decisi-ons are processes that can not occur simultaneously. On a lower level of consciousness, se-veral different things (e.g., driving a car, handling a standard telephone, judging thecharacteristics of information media (Figure 1)) can be performed in parallel withoutthe involvement of higher-level cognitive processing. Successive repetition of a high-level task can decrease the conscious level at which these tasks are performed, which werefer to as automatising a task [Schneider & Schiffrin, 1977; Schiffrin & Dumais,1981].
Figure 1. There are different levels of cognitive awareness. High cognitive awareness meanssingle-processing, but successive routine repetition can distribute a task to a lower level o fcognitive awareness through automatisation.
People’s ability to automatise parts of their behaviour are closely related to cognitiveprocessing and the efficiency in the performance of a specific task. But this knowledge
Level ofcognitiveawareness
Automatisation is thesuccessive transformation ofa task to performance on alower level of awareness.
A high level of awareness,single processing
A low level of awareness,with high capacity forparallel processing
Capacity
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on which parts of an individual’s behaviour is automatic can not easily be observed andcommunicated to other individuals because of its complex environment and lackingawareness by the individual performing the operation. For example, skilled profession-als tend to perform very complex work tasks rapidly, and without any conscious involve-ment, yet them not being aware of doing anything at all. This is closely related to theconcept of tacit knowledge [Polanyi, 1958], referring to aspects on unaware knowledgethat can not be communicated. To solve these problems, there is a need for new methodo-logies that capture design relevant aspects of automatic components.
The importance these theories have for the design of human-computer interfaces i sthe notion that high level cognitive processing should be funnelled to the work itself;i.e. to demanding problem solving or decision making processes. Cognitive processingshould not be consumed on the control of the computer interface or the handling o fother media that should be possible to perform on an automatic level. The user inter-face should be made ”obvious” to the user [Nygren, Johnson, Lind, & Sandblad, 1992].
HUMAN-COMPUTER INTERACTION
Human-Computer Interaction involves a set of processes, dialogues and actions employ-ed by a user to interact with a computer to perform a specific task [Baecker, Buxton,Grudin, & Greenberg, 1994]. We need to extend the scope of this definition to cover a l lactivities surrounding the analysis, design, construction, and evaluation of interactivecomputer systems for human use in a certain physical and psycho-social work environ-ment. The importance of simultaneously facing the effects that information technologydevelopment has on the human being and his competence, on the organisation of thework and on the work activity as such have been known for a long time [Leavitt, 1958].Bearing the historical development of HCI, according to Grudin [1990], in mind, fu-ture research implications aims at regarding everything that in any way might influencethe computer supported work situation. Initially, a hardware focus described the userinterface as something directly coupled to the computer, controlled by programmingoperators. Higher level programming languages freed users from directly handling thehardware. A keyboard and display focus included some early perceptual and motor issu-es. Conversational dialogues between the user and the computer initiated a focus uponcognitive issues. Finally, a groupware focus supports organisations in a social work en-vironment.
With the emerging development of information technology and the increasing com-mercial availability of graphical user interfaces (GUI), the theories underlying GUIsbecome more and more interesting. GUIs are based on the idea of direct manipulation[Schneiderman, 1988; Ziegler & Fähnrich, 1988], where objects in the task domain arerepresented by interface elements. User actions have a high degree of direct manipula-tion if it is illustrated with a visual representation engaging the user in a feeling o fimmediate control. The degree of direct manipulation could be used as a measure of thelearnability of the system but could sometimes come in conflict with the efficiency o fskilled users.
The cognitive engineering philosophy that we find useful, as specified in Norman[1986], describes seven stages of goal driven user activity. When performing a task, a userspecifies an intention based on some goal and translates this into an action that is to beexecuted. The user then perceives the system state and subsequently interprets and evaluat-es this in accordance with the goal. There is a possibility to identify short-cuts in thisseven-stage cycle by providing direct manipulated user interfaces.
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Different approaches to the science of HCI design exist; they all emphasise ratherdifferent views on how to analyse, develop, and maintain computer systems. We havefound this grouping of the different approaches to user interface design appropriateboth to illuminate the background sciences that have influenced the approaches and themethodological aids that have been developed [Wallace & Andersson, 1993].
The craft approach views each design project as unique, where software evolves underthe guidance of a skilled human factors expert. Supporters of this approach tend to beli-eve that a structured approach to interface design is an impossibility, as the aesthetics o finterface design can not be achieved through analytic techniques. It focuses on the desig-ners need for talent, not for methodology. The artistic aspects of user interface designare undoubtedly important, but using this craft view as an argument against methodolo-gies or methodological aids for user interface design, is clearly inappropriate.
The enhanced software engineering approach attempts to introduce HCI techniquesinto the repertoire of traditional systems engineering by various methods for task analy-sis. HCI aspects become an issue for software engineers. Our observations are that theknowledge demands for efficiently being able to utilise HCI techniques, are too big tobe put on software engineers. HCI-issues will inevitably receive a lower priority. Therole of experience is also central, but software development projects tend to be too timeconsuming (e.g., years of development are not unusual), why one individual seldom getsthe chance of acquiring experience from several projects in practice.
To enable ”optimal” design, the cognitive engineering approach aims at applying the-ories from cognitive psychology to the problems facing the designer. Cognitive metricsmodels, such as the keystroke-level model [Card, Moran, & Newell, 1983] measures theuser’s performance time and, thereby, indirectly estimates the memory load for unittasks to help predict the efficiency of different design solutions. The grammar models,with formal grammatical notations, describe the mental models and their incorporati-on into the computer dialogue design. The knowledge methods try to make explicit themental processes of the user when performing tasks. The user modelling methods de-scribe not only what the user must know to perform a task but also how that knowledgeis acquired and manipulated during the execution of a task. The problems of this app-roach lie in the failure of being applicable in real-life development projects due to itshighly complex application of cognitive theories.
The technologist approach tries to solve the problems of interface design by provid-ing appropriate tools, especially the User Interface Management Systems (UIMS), a sys-tem that is both an interface development tool and an interface artefact, consisting of aspecial design environment, a linkage module and a management function. It is usefulfor prototyping and might even be usable for interpretation of formal specifications. Itis, however, no real design support, because design begins long before the first prototypeis constructed. It is merely a tool that allows bad interfaces to be developed more rapid-ly.
DOMAIN KNOWLEDGE AND USER CHARACTERISTICS
We have defined a domain as a class of work activities that bears similar aspects on theworkers situation and performance regarding interaction with customers, case hand-ling, decision making, information processing, and so on. The importance of studyinga domain and acquire domain knowledge for the production of information systems tosupport a work activity is rather obvious. Neisser [1976] argues that instead of spendingtoo much time modelling in laboratories to come up with good models of human-com-puter interaction ”it is a good idea to go out and study in detail how people actually
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work and especially the fine-grained details of the information used in the real world”.Recent research within cognitive ergonomics indicates the importance of extending theanalysis of the interface beyond the visible user interface and instead regard the entiredomain [Fischer, 1993]. The human being is not a passive computer user but an activeproblem solver in some world [Woods & Roth, 1988]. By incorporating domain know-ledge earlier in the development process and in the methods for analysis, design and eva-luation, and by manufacturing formal representations of this knowledge, user interfacedesign for specific work activities can be enhanced. The information the users actuallyuse in their work is important for the establishment of the domain model [Neisser,1987]. By establishing methods for collecting this information and also extend thesemethodologies with aids to capture informal aspects of the work that the user might notbe aware of , user interface design can be enhanced and the resulting user interfaces canbe made more efficient and effective. There are also important ways to reuse softwareengineering components through domain modelling [Arango & Prieto-Diaz, 1991].On the other hand there are evidence for the notion that knowledge of the applicationdomain does not affect the quality of the design [Sharp, 1991]. In structured softwaredevelopment, software engineers are not encouraged to apply their creative abilities andrestructuring the specification of the problem to something appropriate for design.This can not be seen as an argument against domain knowledge acquisition, but as animplication to the need of more structured approaches to the use of domain knowledgein user interface design, for example through the domain specific design methodologi-es elaborated in this thesis.
The difference between novice users, expert users, and skilled users is important inthe domain analysis. Novice users, as opposed to expert users, are unfamiliar with com-puters; expert users have general computer experience, while skilled users are highlyprofessional actors within their complex domain of work. They may be very skilled atperforming their work but unfamiliar with computerised environments. For skilledusers, the computer is only a tool that will be used and appreciated as long as it effective-ly supports the main purpose of the task. Interaction requirements for novices and skil-led users vary greatly and there is often a conflict in these demands. Style guides and stan-dards often overemphasise aspects relevant to novices. This is why we stress the dedicateddesign for skilled professionals when designing in complex administrative domainswith high performance rates.
Field studies show that properties of the work environment can limit people’s abi-lity to effectively use their skills in the accomplishment of a work task. We usually re-fer to these hindrances as cognitive work environment problems [Sandblad, Lind, &Nygren, 1991], problems that are often associated with the user interface. Problemsknowing the present location in the information space, problems interpreting visualcodes with lacking consistency, problems with ”cognitive tunnel view” (i.e., only seeinga smaller subset of a document), loosing the overview, problems with STM overload,etc., are all cases of cognitive work environment problems. Addressing the reasons be-hind these problems is a necessity in the design of efficient human-computer interfaces.
TASK ANALYSIS
An information system will be of no value if it does not contribute to the improvementof the work situation for people in the organisation. Because of this, it is not enough tostudy the contents of the information system, but also the activities people perform in anorganisation and that could somehow be improved [Lundeberg, Goldkuhl, & Nilsson,
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1981]. Task analysis (TA) is concerned with what people do to get things done [Preece,Rogers, Sharp, Benyon, Holland, & Carey, 1994].
TA is a general concept describing methods and techniques that either (a) elicit de-scriptions of what people do, represents those descriptions, predicts difficulties and eva-luates systems against usability or functional requirements, or (b) predict performance,measure system complexity, measure learnability or the transfer of knowledge betweensystems. Hierarchical task analysis methods (HTA) decomposes high-level tasks intosubtasks and operations or actions based on a graphical structure chart notation[Shepheard, 1989]. It involves an iterative process of identifying tasks, categorisingthem, breaking them down into subtasks and checking their accuracy. It is performed inconversation with, and observation of, users working and results in an accurate descrip-tion of the steps required to complete a task. Cognitive task analysis [Johnson, 1992] is,on the other hand, a group of methods concerned with informing the design processthrough the application of cognitive theories, capturing some representation of theknowledge users have to complete a task. One of the most well known is the model hu-man processor (MHP). This model focuses upon the capturing of appearances of theusers mental model of a computer system by predicting and modelling the user’s repre-sentation of the interaction (e.g., through the GOMS-modelling [Card et al., 1983]).The contextual inquiry method [Holtzblatt & Jones, 1993] supports the production o fgeneral purpose systems and provides us with a way to work for short periods of timewith users at multiple customer sites that are geographically dispersed. This providesan understanding of the nature of the user’s work through inquiry with users.
One problem with existing methods of task analysis is that the definition of thetasks that are traced (e.g. key-pressings, or mouse-downs), views too fine-grained detailsof work. Bigger, concatenated tasks make the work context more important, where workcan be viewed upon as simple tasks to be carried out as efficiently as possible, and wheremovement between tasks is important. This task switching [Henderson & Card, 1986;Card & Henderson, 1987] is seldom emphasised in task analysis methods. It is, however,important, if not crucial, for efficient human-computer interaction in a specific worksetting. Important perspectives on the work activity can be reached by dividing the workinto larger units. We refer to these as core work tasks, continuous in time, with a start-ing point and an end point and terminated by a decision. It has been noted in field studi-es that a minimal amount of ”key-pressings” and ”mouse-clicks” are performed among amuch longer period of professional interaction with a work task that contains informa-tion search, judgement and decision making in a typical period of time. Computersupported administrative work of today is no longer about typing as fast as possible,rather to become a professional problem solver using the computer to support this task.The particular tasks that are performed in a work situation are important information,but for the design of human computer interfaces we need methods of analysis describinghow tasks are performed. This is why we propose the method for analysis of informati-on utilisation, to create a directly design controlling domain modelling basis for userinterface design. Task analysis methods should focus on utility and usability to serve itspurpose in practice
DESIGN
Design is a creative activity that involves bringing into being something new and usefulthat has not existed previously [Jones, 1981]. Engineering design is the use of scientificprinciples, technical information and imagination in the definition of a mechanicalstructure, machine or system to perform pre-specified functions with maximum econo-
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my and efficiency. Design refers to both the process of developing a product, artefact orsystem and to the various representations (simulations or models) of the product that areproduced during the design process [Preece, Rogers, Sharp, Benyon, Holland, & Carey,1994]. As a complement to these, we argue for a thorough understanding of the users andtheir tasks. This should result in a maximisation of the satisfaction and entertainmentof using the resulting artefact. Despite these various definitions of design, the term i soften misused for the entire software development process, making software engineersinto user interface designers. This is neither good nor appropriate in that only a smal-ler subset of the decisions that are made during the software development process are di-rectly related to the design.
We have defined design in human-computer interaction as the creation of a formaldescription (e.g., formal language, program code) of appearance and functionality, bas-ed on partly formal and partly informal (to a large extent) results of an analysis. One ad-vantage to this approach is that it treats the creation of appearance and functionality o fthe user interface as separate but related parts, and that different types of products can bedesigned with this definition, such as data base design, organisational design, design o fthe work environment.
The literature on design gives guidance on the essential prerequisites for interfacedesign, but seldom supports the actual design process, even though they claim to do so.The usability engineering approach to design [Nielsen, 1993; Nielsen & Mack, 1994]refers to methods for design such as the various methods for usability evaluation and in-spection. These methodologies are the only formal approaches to interface design thatexists (and that should exist according to this approach). The actual design that is to beevaluated should never be developed based on a methodology. The design rationale app-roach [Moran & Carroll, 1995] serves as a fruitful step for listing the design questions,giving various options and criteria for choosing among these options for the best pos-sible outcome. It is undoubtedly useful for documentation of the reasons for some de-sign decisions. However, the tremendous workload that occurs due to the collection andretrieval of design background information easily becomes too cumbersome to be eff i-ciently used in working life.
User interface design is not just common sense, as shown in an investigation on skil-led designers [Tullis, 1993]. Rather, the acquired skill by expertise in designing userinterfaces is very important for a productive result of an interface design process. In in-house development projects the possibilities for the design team to participate in manydevelopment projects to acquire skill is limited due to the time-consuming feature o finterface development. From our point of view there definitely is a need for a morestructured approach to interface design, identifying different phases and supporting themaking of design decisions with methodological aids and tools. Structured designmethods and opportunistic processing are competing strategies in the nature of designexpertise [Ball & Ormerod, 1995]. A design methodology should not, however, l imi tthe designer’s ability to bring novel approaches to the design process. Due to these res-trictions, the best way to introduce and incorporate design knowledge efficaciously inthe development process is through the introduction of a special design role in the deve-lopment. This designer should be well equipped with knowledge of the user; cognitivepsychology and user characteristics; the development tool and software engineering ingeneral; domain knowledge, analysis methods and human factors issues; and physical andpsycho-social work environment problems. The designer could function as a communi-cation link between different participants in the development team, bringing in aspectsthat otherwise might have been neglected. These aspects include usability aspects, artis-tic design aspects and novel approaches to the performance of the work task with thecomputer support system.
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Are any design methods really used in working life today? The following answershave been found within software development companies1:
No, we do not use any special design method, but...
• we make it as simple as possible for the user.• we follow ”Windows”.• we have employed a specialist.• we discuss the new functionality with the clients and then make a few forms.• if you find any good method, please tell us!
As one easily realises there is a widespread disbelief in the work of finding designmethodologies. There are two reasons for this. Either because the design methodologiesare processes to supply prerequisites to the design and not directly to support the makingof the design decisions. Otherwise the lack of methodologies is made purposely, becauseof the artistic aspects of design argument for talent and experience rather than method.
Standards, style guides and guidelines have been manufactured to guide the designerwhile making of these design decisions. Standards are ”global” documents to supply de-finitions and rules to follow , defining basic functional requirements and quality mea-sures for a user to be able to achieve effectiveness and efficiency in the performing of acertain work task [ISO, 1995]. A style guide (e.g. Motif) provides a consistent look andfeel for products that adopt a specific style guide defining elements and their layout andrules for their use. Guidelines are specific to a certain application area and should sup-port help and guidance in the specific design situation. Design guidelines, such as striv-ing for user interface consistency, have been shown in various situations, to pull the at-tention away from the proper focus (which includes the user, the work task and the un-derstanding of the work domain) of the user interface design [Grudin, 1989]. We arguethat standards today are good and necessary but difficult to grasp and use due to their sizeand complexity. Style guides deal with physical elements and define more exact rulesfor their use, but they do not support any direct design support or support the actual deve-lopment in a specific context. Guidelines are quite useful in specific application do-mains, but their quality and origin might be questionable. In our work, we extend theconcept of style guides to be more domain specific and incorporate domain knowledge.We support our guidelines (heuristics) with empirical evidence [e.g. Nygren, 1996]
Metaphors are important clues to the understanding of the user interface functiona-lity and organisation. Today most graphical user interfaces are based on the desktopmetaphor [Johnson, Roberts, Verplank, Smith, Irby, Beard, & Mackey, 1989]. The basisfor the desktop metaphor is the user’s own ability to arrange the desktop according tohis/her intentions and adapt work patterns according to the arrangement of the workspace. In real working life, we have seen a number of examples of where the rearrange-ment of the user interface takes a lot of time away from the actual performance of thetask, and where a great amount of mental effort is needed for this procedure. In a speci-fic work situation where the user develops skills to handle work tasks with efficiency,accuracy, and with speed, the desktop metaphor becomes unsuitable. We propose an adap-tation of a ”rooms” metaphor [Card & Henderson, 1987; Henderson & Card, 1986] byidentifying workspaces to map certain features, known as work situations. The basis forthis is the idea that all information needed for the performance of specific tasks is al-ways visible on the interface in a workspace consisting of dynamic documents and in-dexes.
1 Eva Olsson at CMD is acknowledged for having performed this inquiry.
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PARTICIPATORY DESIGN AND USER INVOLVEMENT
Traditional researchers state that results that have not been obtained in the laboratoryare of no scientific value and therefore useless in practice. With the speed that thescience of HCI develops it is both unwise and impossible to subject every observation tolaboratory research. To develop a good model demands too much time in the modellinglaboratories. It would be much wiser to go out and in detail study how people actuallywork and especially the fine-grained details of the information used in the real world[Neisser, 1976]. The majority of the results outlined in this thesis includes observationsfrom real development projects, so-called action research. This means that the resultsmight not have general applicability. A common opinion is that when constructingcomputer support for the user, it should be rather obvious that the user him/herself i sthe person best suited to design the user interface. Many models and methods for UserCentred System Design exist, emphasising the study of the user in the production o fhuman-computer interfaces [Norman & Draper, 1986]. Unfortunately, too little evi-dence can be found on the practical use of a user centred design methodology. Today’smethods for system development are old and emanate from the times when interactiveend-user applications where popular and important. The development of these seldomfocus on the user and his/her task. This knowledge led to the development of (what i sknown as the Scandinavian approach) participatory design [Schuler & Namioka, 1993;Greenbaum & Kyng, 1991], with the general assumption that the users should be notonly involved, but in control of the analysis and design process. Cooperative design[Bjerknes, Ehn, & Kyng, 1987; Ehn, 1988] emphasises cooperation with the end-user’sunion organisations to amplify the legal and democratic right of the users to influenceand control the work situation of the future; the user is in direct control of the systemdevelopment process. The iterative process of analysis, design, testing and redesign in a”spiral” model has been emphasised, in Boehm [1988], for example. Organisationalaspects can, in some cases, work against user participation.
Users are of an undisputed importance in the user interface analysis, design and eva-luation phases but, according to our observations, users are not always aware of theirwork behaviour, nor are they experts in design and human-computer interaction. This i swhy a user controlled design methodology can have negative effects on the usability o fthe resulting information systems.
There is apparently a need to bridge the gap between developers and users. One wayto do so is to introduce external consultants or independent developers as ”bridges”. Onecan distinguish among three different types of development [Grudin, 1991a], and theyall have different varieties of the involvement of users and developers.
• Contract development focuses upon software development methodologies; forexample, the waterfall model is a structured model of information system develop-ment involving; establishment of a development plan, requirement specifications,preliminary design, final design, coding, testing, integration, installation, runningand maintenance. It is restricted to a ”build it twice design”; a prototype is construct-ed and tested in the design phase and the final system is then constructed based onthese evaluation results. The reliance on written documentation as aids for commun-ication between developers and users tend to build walls between them, aggravatingiterative user centred design.
• Product development focuses upon the user interface with an apparent need to manu-facture attractive entertaining systems because it is the market; the client that separat-
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es the users from the development. The client is in many cases not the typical user,rather a manager or information system specialist.
• In-house development focuses upon user participation. Because the earlier mention-ed tendency of documentation to constitute a wall between developers and users, theyneed to be brought into physical contact. An adaptation of the organisation is oftenneeded. This is the type of development that our research group at CMD mainlydeals with.
In a recent Swedish study, a survey was made, trying to rate the usability maturity o fSwedish working life [Katzeff & Svärd, 1995]. Particularly important factors were:Formal and organised usability competence, and; Integrated usability in the design anddevelopment methodologies. The survey showed that the development of methods forthe development of usable systems received the highest rating. This is in line with ourexperience that enhancing the methodologies for participatory design in in-housedevelopment companies receives the greatest attention and addresses factors relevant forevery participant in the development process. Achieving more usable systems is a goalfor everyone, there are only different ways, with different results, to reach the goal.
EXPERIMENTAL SYSTEM DEVELOPMENT
Computer systems that are to be used by human beings should be (a) Easy to learn, (b)Usable (in relation to the task that is to be accomplished), (c) Easy to use, and (d) Pleasantto use [Gould & Lewis, 1988]. To reach these goals, the designer needs an understandingof who the user is. The presumptive user should be working close to the design team inthe early developmental stages and physically use prototypes for their behaviour to bemeasurable. Iterative design is needed with a cycle of design, test, measurement and re-design etc., in order to create efficient and effective user interfaces. In working life de-velopment projects, these design principles are often highly underestimated for severalreasons, such as the diversity in use and user characteristics are often underestimated, toomuch confidence is put on rationales and reasoning for establishing how tasks are to beperformed; there is a common belief that guidelines are sufficient prerequisites for a”good” design; users do not know what they need; there is a belief that ”good” design i s”getting it right the first time” and that iterative design is merely ”fine tuning” of theinterface, and risk that the development process might be delayed.
In working life of today, most development methodologies are still adaptations o fthe waterfall model of systems development, that is, successive stages of operational plans,operational specifications, coding specifications, coding, parameter testing, assemblytesting, shakedown and system evaluation, with each producing rigorous documentation.In in-house development projects, it is very common that the large amounts of documen-tation, produced as results of the task analysis, create a wall between developers and users,and especially so if developing according to the waterfall model. It is our experiencethat the documentation produced is seldom used in the interface design phase, either be-cause they are insufficient or because they are too large and extensive and hence impossi-ble to overview. With an iterative spiral model of continuous analysis, design, evaluati-on and redesign, etc., development and maintenance of larger information systems can beenhanced [Boehm, 1988]. Such a model has shown to be problematic if it is directly app-lied to working life, because of the problems of keeping down the iterative life cycletime. Also, the problems related to time and interest by the developers to learn new deve-lopment methodologies, and the complexity in the knowledge demands on the design
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phase are some reasons why we propose the development of a certain design competencein the iterative experimental system development process, with essential knowledge pre-requisites and methodological tools such as analysis of information utilisation and de-sign methodologies.
EVALUATION METHODS
Evaluation methods have become an increasingly important tool for user interface de-sign and need be incorporated into the system development process. We can separate eva-luation methods into usability testing methods (i.e. where users are involved) and usabi-lity inspection methods (i.e. where users are not involved).
Usability Testing Methods
Performance measurement [Nielsen, 1993] collects data on errors and times to determi-ne to what extent a usability goal is reached by having a group of test users perform apre-defined set of tasks in a laboratory. This method allows a quantitative comparisonof the usability of different design solutions. The method is expensive, complex, andtime consuming to use. Moreover, the laboratory tests are difficult to perform early inthe design process because it requires a running prototype and a reasonably complete database. More abstract goals can not be measured using this method.
Questionnaires [Nielsen, 1993] are useful for judging users’ subjective satisfactionand anxieties. Questionnaires are inexpensive and may be distributed to many users.However, end users are not able to judge their satisfaction when they have acquired thenecessary skills. This is why questionnaires does not identify usability problems concer-ning efficiency in daily use.
Thinking aloud is a method in which a usability expert notes how users view thecomputer system by verbalising their thoughts while using the system. It is an inexpen-sive way to identify users’ misconceptions of a system. Unfortunately, it is not naturalfor users to think out loud while performing work, and there are many automatisedinformation handling routines that the user might not be aware of in daily use.
The pluralistic walk through [Nielsen & Mack, 1994] involves users, developers andusability experts, and may be carried out early in the design process. Representativesfrom the three categories meet and discuss usability problems associated with thedialogue elements in scenario steps. The main focus is on how users react in differentsituations. The method is effective in evaluating the learnability of a user interface, butis not appropriate for evaluating interfaces in daily use. Users are not able to predicthow they will interact with a system when they are skilled.
Usability Inspection Methods
Cognitive walk through [Nielsen & Mack, 1994] is a method through which an evaluatorexamines each action in a solution path to tell a credible story describing why the userwould choose certain actions. It is based on assumptions about the users background,knowledge, goals, and an understanding of the problem solving process that enables auser to guess the correct action. The method focuses on evaluating a design for ease o flearning, particularly by exploration and is, therefore, not applicable for inspection o finterfaces for skilled users.
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Heuristic evaluation [Nielsen & Mack, 1994]is performed by an evaluator using a setof guidelines (i.e. heuristics in form of a checklist) to judge the usability of the userinterface. It is easy to learn and inexpensive to use. Many usability problems can be tra-ced and it is usable early in the design process. Evaluators using this method, however,seldom manage to identify domain specific usability problems due to a lack of domainknowledge by the developers. Mostly general usability problems can be identified withheuristic evaluation. Heuristics suggested in Nielsen [1993] emphasise ease of learningand are not "optimised" for efficiency in daily use.
Domain-specific Evaluation Methods
Apparently there is a need for evaluation methods that focus upon efficiency in daily useand ease of learning. We also need methods that identify both general and domain speci-fic usability problems. To be usable, the methods also need to be efficient, easy to useand possible to adopt early in the design process. A method to fulfil some of these goalsis the method of domain specific evaluation that identifies general usability problems byan adapted heuristic evaluation method, and domain specific problems through an eval-uation together with domain experts to be used early in a user-centred design process[Lif & Sandblad, 1996].
The ADA-method [Sandblad, Åborg, & Lif, 1996] is another method for evaluatinguser interfaces for skilled professionals when they have become skilled at using the newsystem. It is performed by a usability expert categorising usability problems in accord-ance with a specific task through observation-interviews.
DESIGNING FOR USABILITY –DOMAIN-SPECIFIC DESIGN OF USER INTERFACES
In this extensive introduction to the problem area, the need for domain specificapproaches to modelling, analysis and design of human-computer interfaces in workinglife. Below, I will describe what our contributions are to the problems described aboveby briefly summarising the papers in the thesis and their interrelationships. This thesishas been divided into three parts: Part I: Methods and tools for HCI Development; PartII: Domain-Specific Design and Domain-Specific Style Guides; and Part III: The CaseHandling Domain; Field Studies, Models and Applications. The purpose of this divi-sion has been to separate and group what I regard as theoretical reasoning and ideas, thedomain specific approach and strictly applied research work.
I. Methods and Tools for HCI Development
This part of the thesis explains theoretical ideas and foundations, upon which we havebased the defined methodologies and methodological aids. It establishes a new defini-tion of the concept of design within human-computer interaction and stresses the needfor a more structured design methodology. It specifies the method of analysis of infor-mation utilisation and gives design heuristics and metaphors for design dedicated to aspecific class of work. The results have been generalised and examples from several do-mains of work are given.
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1. Efficient Development of Organisations and Information Technology –A Design Approach.
In the first paper, a framework for the entire process of organisation and informationsystem development is defined as a structure for the entire process of organisational andinformation technology development, consisting of separate but sequentially relatedparts (Figure 2).
Application development
Organi-sational
model
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3
4Infor-
mationanalysis
Information utilisationanalysis
Appli-cation model
Work model
UserInterfaceDesign
Inter-face
model
Con-struc-tion
Organi-sational develop-
ment
1. Data- base2. Appli- cations
UserUser
User
User
Activities – work processes (analysis, design, construction)
Descriptions – resulting formalised models
Figure 2. Iterative experimental system development; including consecutive activities and thedescriptions they produce. Feedback and possibilities for participatory design are also illus-trated.
The different development phases (activities) and the resulting models (descriptions)are defined focusing especially on design issues. As mentioned before, the meaning o fthe concept design varies depending on the discipline and even on which researcher thatanswers the question. We have defined the process of design in human-computer inter-action as the process of creating a formal description (e.g., program code, prototype, etc.)of the appearance and functionality of an information system. This design is based onboth formal and informal descriptions of interaction requirements as a result of a workanalysis process. Informal aspects that are encountered in the analysis process (i.e. workroutines that the user might perform without him/her being aware of it, or propertiesobserved by the designer without it being possible to formally describe) are veryimportant for the creation of efficient user interfaces. The analysis phase is separatedfrom the design phase; while documenting the results of the analysis, no designdecisions should be made. It is a point to try to produce work descriptions in thelanguage of the work activity, without involving design terminology. With such adefinition we can speak about organisation design, database design, interface design andprogram code design (construction).
According to the definition of design as a specification in a formal language, it cannever completely describe all requirements. In the design process, four different con-secutive gaps of communication can be distinguished, in which important informationabout the actual work situation could be lost. These gaps refer to the formalisation o fthe process of organisational development, data modelling, work descriptions andinterface design specifications. The gaps can constitute severe obstacles in the process o fdeveloping efficient and usable information systems for specific work situations. Byintroducing development models that covers the entire process of design, these gapsmight bridge, or at least narrow. Some main characteristics of such models are presentedin this paper.
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2. The Nature of User Interface Design –The Role of Domain Knowledge.
The importance and growing awareness of domain knowledge acquisition in informa-tion system development, and especially in the process of design of human-computerinterfaces, is becoming more evident. But the introduction of participatory design tech-niques and user centred system design are, although necessary, very difficult to efficient-ly adopt in working life. The basis for the discussion is the focus on skilled profession-al users, using computers to support the performance of a complex work task. In severalin-house development projects, methods for efficiently capturing and utilising domainknowledge have been defined and tested (e.g., through the definition of domain-specificstyle guides and methods surrounding these). Also, methods for modelling case handlingwork in general terms, which is the main application focus of our studies, have beendeveloped and tested in larger corporations.
The second paper aims at relating domain knowledge models to conceptual modelsin information system development and to user models in human-computer interaction.Based on Norman's [1986] model of user perception of an existing computer system,different limitations are identified and possible extensions are discussed. By introduc-ing the domain context, several additional models of the work task by the user, as well asthe designer, occur. If the dynamic iterative system development process is regarded,further models and dynamic changes in the models over time can be traced. Thedifferent mental models by the participants in a development project are identified andtheir changes over time because of the iterative experimental system developmentprocess, are discussed. Furthermore, these models are related to the state-of-the-artknowledge on mental models and domain modelling. Implications for design, such aswork modelling, iterative system development, analysis of information utilisation,design and evaluation methods, are discussed.
3. Analysis of Information Utilisation (AIU)
As outlined previously, task analysis methods are necessary but insufficient for derivingspecific knowledge that is directly applicable for user interface design. The third pa-per describes analysis of information utilisation (AIU), a method for the specificationof how information entities encountered in the information analysis are being physi-cally manipulated in a work situation. AIU focuses particularly on factors affectingcognitive load. The method supports the human-computer interface designer with rele-vant and appropriate information structured specifically for a document oriented de-sign methodology, what we call design controlling information. It gives a suitablebasis for user centred interface design, without the possible limitations that improperuser participation could cause. It focuses on all aspects relevant for a ”good” work envir-onment (e.g., human competence, work organisation, work activity and informationtechnology development).
Analysis of information utilisation is performed through ”observation-interviews”in which a human-computer expert interviews a typical user about his work situation inthe domain of work and observes information handling routines that the user might notbe aware of. Every analyst adopt individual patterns of how to conduct such an interview,why we do not support special instructions on this. We rather present a framework forthe documentation of these analysis results for the incorporation in the design process. Anumber of development projects has shown that this method can constitute an additionalstep in existing methodologies for capturing aspects of the work situation that can be
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directly design controlling. The paper describes the method of analysis of informationutilisation, and what information that has to be documented while performing the ob-servation-methods. It suggests how the method can be incorporated into existing in-house development methodologies, and gives an example of documented analysis resultsfrom a development project within the Swedish National Tax Board.
4. Work Spaces and Rooms in User Interface Design.
Design of graphical user interfaces are today mostly based on the desktop metaphor andwindow-based analysis and development methodologies. These methods particularlyfocus upon the spatial design of windows and navigation by means of menus and buttons.Window-based computer systems have totally come to dominate the commercial market.Originally, this metaphor was not developed for in-house development of dedicatedcomputer support systems for professional users. Even if it means stepping aside fromexisting standards and style guides, other basic structuring methods should be consideredwhen today’s methods aggravate efficient performance in a work situation.
The purpose of the fourth paper is to identify differences between two approachesregarding the basic structuring of user interfaces to computer systems for skilled profes-sionals in working life. The first approach to the design of an information system i sbased on a detailed analysis of the total number of work processes of the organisationunder study. A basic design problem is to show all available functions of the system tothe users, and supply them with efficient facilities for navigation from the overviewstate to the desired state where a specific task can be performed. The second approach i sbased on an analysis where tasks, relevant to each individual in the organisation, areidentified. A design goal is to specify an efficient interface for each group of individu-als (or work role). The proposed design has been inspired by many concepts from the”rooms design” metaphor [Card & Henderson, 1986]. By separating different roomstructures for groups of individuals and base the design of screen documents on domainknowledge, tailored and efficient interface structures can be obtained.
5. A Structured Approach to Prototype Design in Iterative SystemDevelopment.
As mentioned before, existing methodologies for design focus upon the capturing of de-sign rationales, methods for domain analysis, or evaluation methods to name a few.There is little or no support for making design decisions; rather, design is regarded asan artistic process that can be improved only through experience.
This fifth paper presents a structural approach to the iterative process of designingeffective and efficient human-computer interfaces. Different phases of the design pro-cess are identified. Four different phases of the design process are described: Identifica-tion of the information contents, specification of the layout, dialogue structure, and thebehaviour of the user interface. Design decisions made in these phases are based on a setof domain specific heuristics. Prerequisites for the user interface design process is ananalysis of the domain, the users, and the technical environment. Based on this, a suitablemetaphor can be chosen. A “workspace metaphor“ supporting administrative work in abroad sense performed by skilled professionals is introduced. By creating interface ele-ments and workspaces in an iterative design process, a first prototype can be defined. Thefollowing user characteristics are important. (a) Cognitive processing on a consciouslevel is a limited resource. (b) Transferring information via keyboard and/or mouse i s
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a slow process as compared to the swiftness of cognitive and perceptual processing. (c)Experienced users decode frequently occurring, meaningful patterns quickly. Thesethree constitute a basis for two general design goals: (1) Design an interface that mini-mise the users cognitive processing on a conscious level. (2) Create a design that w i l lminimises the time the user has to deal with the keyboard and/or the mouse. These goalscan be fulfilled if the designer knows the frequency by which the information entitiesare needed and the technical limitations of the computer system and its software. Resolv-ing conflicts between the two goals are a major part of the designers work. Some designexamples emphasise the resulting design, basing it on those heuristics.
II Domain-specific Design and Domain-specific Style Guides
The importance of incorporating domain knowledge early in the development processwas stressed in the previous section. Of course, there are many ways of doing this, but notso many that efficiently supports the design process. By introducing a domain specificstyle guide, i.e. a higher level of interface elements with element specific guidelines in-corporating domain knowledge, development can be enhanced. The development can beperformed quicker and cheaper, with better possibilities to achieve efficient user parti-cipation and to produce more usable interfaces. This section introduces the concept o fdomain specific design and relates earlier methodological tools to this technique.
6. The Need for New Application-specific Interface Elements.
The design of user interfaces for skilled workers in professional work settings shouldbe based on style guides that certify efficiency. Most of toady’s style guides and designguidelines over-emphasise general aspects or aspects relevant to novices. To increaseefficiency both of the design process and of the resulting interface, more domain speci-fic interface elements should be used. This sixth paper explains the basic ideas of suchdomain specific style-guides and gives some examples from the health care domain.Interface elements that are described are: The document, consisting of one or more pagesin a bundle, improving the possibility of recognition of spatial location; the index,containing information on the contents and structure with graphical features; miniatur-es (i.e. a proportional diminution of a screen object) that can be recognised through theinformation patterns it create; and more complex element combinations. The point i sto incorporate domain knowledge already in the element structure and present these in adomain-specific style guide.
7. Domain-specific Design of User Interfaces.
The use of graphical user interfaces in a computerised work environment is often consi-dered to substantially improve the work situation. The outcome can, however, often bethe opposite. Inappropriate use of windowing techniques, scrolling and colours can re-sult in tedious and confusing interaction with the computer. Today's standards and styleguides define basic design principles but are insufficient for design of interfaces to enduser applications. Here detailed domain knowledge is indeed essential.
This seventh paper describes the domain-specific style guide (DSSG) as an extensionof today's standard with domain-specific primitives, interface elements, and forms, to-gether with domain-specific guidelines. Careful dedicated analysis of information
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utilisation in a domain is the development basis for a DSSG. The development is per-formed with an object-oriented approach to facilitate the reuse of interface componentsand to support consistency and structure. By using a DSSG, the development of applica-tions can be performed with a simplified information analysis. Therefore, a moreeffective design process is possible, one in which end users can participate in the designusing their own familiar domain-related terminology. Time and costs for the develop-ment process can be drastically reduced if domain-specific style guides, design guide-lines, and development tools are used.
8. Domain-specific Design of User Interfaces –Case Handling and Data Entry Problems.
New approaches on human-computer issues are required in designing user interfaces forskilled professionals in specific domains. By including domain knowledge earlier inthe development process, applications development can be simplified. The advantagesof a domain specific design are obvious: (1) It provides increased efficiency in the deve-lopment process and in the final application; (2) It enhances the possibilities for effec-tive user participation; and (3) It reduces development time and cost. Domain specificdesign requires a careful analysis of information utilisation. The analysis results in adesign specified in a special design language interpretable by the construction tool.
This paper outlines a framework for a domain specific design and developmentprocess. Design was earlier supported mainly by cognitive theories on human computerinteraction and user modelling. In the domain specific approach, design issues are con-centrated on efficient development of effective human-computer interfaces. Our purpo-se is to identify the major steps of the process – analysis of information utilisation, de-sign and construction – with special emphasis on their documentation. The differentdocumentation can be seen as interfaces or bridges between preceding and succeedingsteps in the development process, and are to be specified in some kind of formal or semi-formal language. We are currently working on the specification of these languages. Ourdevelopment process can be compared with development using traditional UIMS, withemphasis on the possible benefits, such as cost and time savings, increased possibilitiesfor effective user participation and increased modularity.
The domain of case handling accentuates the domain specific development as a gene-ral approach on a large number of administrative work situations where case admini-strators interact with customers or clients. Case handling is an important domain withmany end users using their skills for complex information retrieval and decision mak-ing. This domain is described from the case administrators perspective on customerinteraction, information retrieval, decision support and information systems. We stresssome general aspects on case handling, which are important for the design of efficientcomputer support for personnel working in this domain. Some basic work flow enti-ties, to describe and categorise the case handling domain, are presented. These includethe initialisation phase, the information retrieval process, the case administrators deci-sion process, and the documentation and information services.
III. The Case Handling Domain;Field Studies, Models and Applications
Most of our research has been applied to case handling work (e.g., tax administrationwork, bank and insurance, personal administration). Case handling is a general concept
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describing work that bears similar aspects concerning client approaches, informationstructuring, judgement, decision making and archiving. By attacking these problemswith a mutual approach, synergetic effects concerning usability and human-computerinteraction can be reached. This section aims at describing current research within theSwedish National Tax Board, applying theories described in the previous sections.
9. Case Handling Models as a Basis for Information System Development.
Computer use in administrative work is increasing rapidly and today most of the casehandling activities depend heavily on computer support. As a consequence, usability pro-blems are increasing due to the complexity of the information systems, which consist o fmany different software technologies that need to be combined together in an appropri-ate way. Software is often developed in in-house development projects, and sometimeseven in combination with adaptations of various off-the-shelf products. The load on thesoftware development team becomes enormous, and their possibilities for developingstandards and reusing software components are limited. A general approach to case hand-ling work through mutual concepts and process flows is a basis for being able to deve-lop a domain specific style guide (DSSG) for the case handling domain.
In this paper, we have modelled the case handling domain based on work activitieswithin the Swedish tax administration. It has been performed in a user centred way andthese models have been tested and validated in a number of other work activity areaswithin the organisation. We suggest how case handling models can be used in an effecti-ve way when analysing and designing information systems for case handling. The im-portant aspects that stem from the synchronisation of this technology development withorganisational, competence and work activity development being emphasised. Such aframework should be a necessary prerequisite for domain-specific design of case hand-ling work.
10. Domain Specific Design in Practice: Tax Handling Work.
This paper describes the state of the art of an ongoing development project within theSwedish National Tax Board. The project aims at introducing the technique of do-main specific design, increase the developers competence in the area, and participate inthe design and the development of a domain specific style guide for the Swedish Nati-onal Tax Board (RSVSG). Important aspects of domain specific design that this projectstudies include; the introduction of new methodological steps in the existing softwaredevelopment life cycle; the specification of workspaces and the methodological aspectsof identifying major work situations; the structure of the domain specific style guide;and, finally, we will give some implications for the future work within the project.
11. Designing Graphical User Interfaces under the Limitations ofOld Alphanumeric Mainframe Systems.
A common problem in in-house development projects is the tendency to be so dependentupon existing information systems that the only possible development solution is to ex-tend the computer environment with new client-server applications, and thuscommunicating with the older alphanumeric mainframe systems. Maintaining andrefining existing software receives higher priority than building new computer
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environments. In our work, we have observed and identified these problems in severalcase handling work activities and studied the impacts these problems have on end users. Abetter work environment, minimising the cognitive load caused by the handling of theinformation system, can be achieved by approaching these design problems through theapplication of design heuristics specific for the case handling domain, and by a we l lthought out compromise due to these technical limitations.
GENERAL DISCUSSION
Because of the increasing psycho-social, physical and cognitive problems in computeri-sed work environments of today, there is a strong need to improve the work situationsfor the thousands of computer users that today suffer from badly designed computersupport systems. Evidence can be found that some of the work environment problemsfound in real life work situations are related to the efficiency and usability of thecomputer support. Numerous field studies have shown decreases in work efficiency andsatisfaction due to the introduction of computer based information systems into we l lfunctioning paper-based work situations. There is definitely a need for efforts aimingat the improvement of the human-computer-work interaction situation. For example, aredesign of displays in an American telephone company decreased the average searchtime by an amount translatable to 79 person-year savings per year [Tullis, 1981]. S t i l ltoday, a lot of new development of character-based user interfaces occur in working life,despite nearly 15 years of commercially available graphical user interfaces. Generally,graphical user interfaces are more effective than character-based interfaces, but for taskswhere the main part of the interaction is input, old-fashioned interfaces are often better[Rauterberg, 1992]. Although having a nicer look-&-feel, the graphical user interfacesare sometimes less efficient for skilled professionals.
This thesis has described a structured approach to organisation and informationtechnology development, focusing especially on analysis of information utilisation anduser interface design. The need for structured methods incorporating work activity,organisation, human competence, and information technology development have beenstressed. Embryos to the method of analysis of information utilisation and designmethodologies have been presented. Advantages have been noted, we have been involvedin, using the analysis of information utilisation in our development projects. Designmethodologies in the form of design heuristics for skilled professionals have been de-fined, related to empirical measurement and practically used in development projects.Concerning organisational development no methodological aids have been presented,rather, the need for adapting the work organisation to information technology changeshave been discussed through the introduction of ”learning organisations”, i.e.organisations that automatically adapts to required changes. The information analysishas not been given much space due to the acceptable quality of existing methods, butobject-oriented design methodologies [Booch, 1990; Rumbaugh, Blaha, Premerlani,Eddy, & Lorensen, 1991] are essential prerequisites for achieving modularity and pro-moting software reuse in the development process. The present thesis briefly mentionsconstruction and implementation aspects, but without supporting any tools or anygeneral advice. These are aspects that we need to further study in detail. Our researchgroup is currently working on a tool that automatically generates a functioning userinterface, by interpreting a design description file, together with an existing databaseand ”methods” describing the behaviour.
Domain-specific design aims at creating a higher-level platform for system deve-lopers, designers and for work activity representatives. It is a well known fact that gene-
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ral style-guides and standards overemphasise aspects relevant for novices, or aspects relev-ant for learning to use the interface. With the domain-specific design methodology, de-velopment of user interfaces for skilled professionals in a specific work setting can beenhanced, and thus effectively supporting the accomplishment of individual perform-ance of tasks. Ideally, development should be possible to perform in cooperative sessionswith designers and users, structuring the interface from a set of pre-specified interfaceelements, containing domain knowledge. To what extent the domain specific styleguide can be used in a specific application project and how much needs to be re-designed and incorporated into the style guide is yet to be tested and evaluated. We arecurrently adopting the technique in development projects for the Swedish NationalTax Board, and the full experience will have to wait a few years to be fully documented.However, so far the ideas and applications, design methodologies and prototypesdescribing the technique and the resulting user interfaces have been received with over-all positive judgements, both by developers and user representatives.
The establishment of a tax case handling style guide should be based on a commonconceptual framework describing and defining general concepts and processes withinthe organisation. We have participated in the user centred development of such a frame-work and evaluated its general applicability on other case handling work activities.Work on a refined establishment and use of the case handling framework have recentlybeen restarted. So far, the results and responses of the establishment of a common concep-tual framework and mutual process descriptions for general case handling work havebeen well received within the organisation. The establishment of methodologies forusing such a framework, for basing user interface development on the framework, foridentifying needs for organisational changes, competence increase, and business processreengineering are yet to be performed. Also, rules and regulations for updating and dy-namically adapting the framework to new work activities and work routines are to bespecified. Other official authorities have expressed an interest in establishing similarcase handling frameworks.
Future research will focus on describing and refining all steps in the organisationand information technology development, according to the structure described in paperone. The development and introduction of domain specific style guides and designmethodologies in working life application projects will be evaluated. The casehandling framework will be further elaborated and applied to specific work activities.Methods for the use of the case handling framework will be defined, as well asorganisation and rules for updating the framework. It is important to incorporate andbase the development of the domain specific style guide on this framework, identifyingbasic elements and information structures.
These methodologies strive to enhance development by decreasing the iterative sys-tem development time, supporting high level interface elements and guidelines and bythe incorporation of domain knowledge. Thereby, development can be performedquicker, better and with reduced development costs. By decreasing development time andrestructuring the development process, developers and designers have the possibility o facquiring design expertise, because of the possibility to participate in several develop-ment projects using the same tools.
Despite the tradition of user centred and even user controlled design methodologies[Bjerknes et al., 1987; Ehn, 1988; Greenbaum & Kyng, 1991; Schuler & Namioka,1993], many problems with user participation in the development process exist[Grudin, 1991b]. Cognitive, physical and psycho-social work environment problemsmust all be considered in order to obtain increased work efficiency, improvedeffectiveness, and a better work environment. Although user participation is difficult,because of the complexity in the work tasks for which computer support is being
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developed, it is absolutely necessary for in-house development. We increase thepossibility for more effective user participation in the development process and hope toincrease the satisfaction and efficiency of computer use in daily, working life forskilled professionals.
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