Training computer-supported work by simulation

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Training computer-supported work by simulation Inger Eriksson Department of Computer Science, Abo Akademi, The Knowledge and Work Research Group *, SF-20520 Turku, Finland

Pekka Reij onen Department of Psychology, University of Turku, The Knowledge and Work Research Group *, SF-20520 Turku, Finland

Simulation has traditionally been used to describe complicated systems, to plan expensive or otherwise critical systems, and for education. A rather new domain for simulation is information systems design and use. We claim that simulation with its various techniques can profitably be used to improve end-users' competence to use a computer-supported information system in work situations and to participate in systems development. The claim is based on the following facts. The main difference between information systems and other systems, for example, a manufacturing system, is the level of abstraction. Simulation is one of the best ways to concretize abstract concepts and relations between them and therefore it offers good opportunities to facilitate learning processes. Econo m y is another good reason for using simulation in training work situations. Technological development will facilitate the use of simulation, animation and graphical representation; so we expect more transparent, self-explaining, and easy-to-understand systems for the future.

Keywords: Cognitive model, Computer games, Concretization, Information system, Learning, Mock-ups, Participation, Prototype, RSle-play, Simulation, Simulators, User training, Work situation.

Inger Eriksson is Licentiate of Philqsophy in Computer Science at the Abo Akademi University in Finland. She is a m e m b e r of the Knowledge and Work Research Group and also a researcher in a project on software quality, the SOLE-project, at the A b o Akademi University. Her previous work mainly concerned contents and techniques for end-user training. Her current interests include the use of simulation as a learning technique. Thus improving the quality of the use of information systems is the main topic of her coming Ph.D. thesis. * The Knowledge and Work project (1986-1989) at the University of Turku, led by Professor Markku I. Nurminen, is mainly financed by the Academy of Finland. Education & C o m p u t i n g 6 (1990) 129-136 Elsevier Elsevier Science Publishers B.V.

Introduction

Traditionally, simulation has been used to describe complicated systems, to plan expensive or otherwise critical systems, for demonstration and education, and for calculating matematical or numerical solutions. A rather new domain for simulation is information systems design and use. In this paper, we discuss how simulation could help users to participate in systems development processes and to use these systems efficiently. We claim that simulation might be a useful way in improving users' qualifications to make information systems support their ordinary work. The benefits and drawbacks of simulation, compared with other techniques, are discussed and some future prospects in this field are developed. The concept of simulation is not altogether straightforward. Here, we give it a very broad meaning, including: computerized simulation of activities and functions, rSle-play, various games, and models, such as simulators and mock-ups. Simulation can be categorized into three basic types, namely, game simulation, field simulation, and rSle-playing simulation [13]. In game simulations, players play the game as if it were real. The participants take rSle in particular staged situations and maintain them until a desired outcome is reached or a given time is expended. Field simulations are performed in highly realistic settings to make participants feel that they act in a real situation, rather than in a simulation. Also, in r~le-playing participants are asked to pretend that a situation is real when it is not. It is, however, more flexible and permits great use of imagination. This technique can be differentiated in terms

Pekka Reijonen is a m e m b e r of the Knowledge and Work Research Group. He received his master's degree in Psychology at the University of Turku. He has been studying learning strategies and developing multimedia C A L programs for language learning. His current interest in information technology is how to create understandable, user interfaces.

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of active or passive action. The rSle can range from totally improvised to highly scripted. It is also possible that one person plays more than one r81e. The remaining part of this paper is organized as follows. In the next section we discuss domains where simulation is used. This investigation is based on current literature and research, as well as on some experiences of our own. To sum up, a classification of the different simulation approaches is made in the third section. In the fourth section, simulation in systems design and use is evaluated from different perspectives. In the fifth section, some future prospects are presented.

Use

of

simulation

Simulation in work situations, especially training in these, is our main interest. Some kind of structuring is, however, needed in order to keep an overview and not to get lost in details. The purpose of simulation is often to support problem solving. Consequently, the application areas could be described according to the type of problem. The following structuring has been proposed [2]: - description of systems, - planning of systems, - demonstration and education, and - mathematical or numerical solutions. This structuring is not quite adequate for us since we are not studying simulation as such, but simulation used in work situations. On the one hand, the last domain, solving mathematical and numerical problems, does not fit our needs, so it is excluded in what follows. On the other hand, a new problem area, design and use of information system, is included. Description of systems A system is described in order to facilitate understanding of its structure and behaviour. Simulation models are designed to explain complicated organizations, competition between enterprises, and macro-economic processes, for example. Describing information systems with the help of simulation might also be included in this category. Alternative approaches to simulation are mathematical models (operational analysis), but these have proved too simple to represent the

behaviour of a real system. Simulation models are used for several kinds of analysis purposes [6,19]. M a n y prognostic and predictive models can be regarded as descriptive simulation models [30]. Also, m a n y decision-support systems and spreadsheet applications are such models, with the purpose of answering w h a t - i f questions [15]. However, for these types of simulation there exists the same problem as with statistics. It is possible to say something about general behaviour, but noting about each specific occurrence. Planning of systems In working life, it is seldom enough to understand the structure and behaviour of systems. This understanding should be used to control the system or to improve it in some way. Planning systems means that a model of the existing system is built. Experiments with this model are then made until it functions according to the demands. The real system is then adjusted in a corresponding way. If there is no old system, then the model is designed according to goals, assumptions, and guesses about the future system. In the process industry, simulation is used both to plan and control continuous processes. This category also includes models of complicated control systems in military and space industries and of real physical systems, such as aeroplanes, vessels, and cars. These are designed as simulation models and tested before a prototype version is constructed. Also, communities and organizations use simulation for planning purposes [23,31]. Another category of systems which is often planned using simulation techniques consists of so-called traffic systems. These might be manufacturing and maintenance systems (see, e.g., [12,14, 18,26]). Their purpose can be to find out the fastest or smoothest through-put, m a x i m u m safety or minimum cost for (some part of) the system. Demonstration and education Technology is radically transforming a host of occupations. For example, an estimate for the U.S.A. indicates that, by the turn of the century, millions of jobs will involve robotics and laser technology [24]. Consequently, training and education have become important parts of working life. Complicated processes, which will obviously

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increase in number, are better demonstrated by models simplified in some sense as to their structure, time or space dimension, and comprehensibility. Macro-economic processes belong to this category of problems. The dynamics of work processes, enterprises, organizations, and communities are more easily described by simulation than by mathematical models, or verbally. Such models can be used when new employees are learning how the system works, but they are also useful when analysing errors and their possible causes and consequences [21]. Several types of computer games (managerial, military, society) are good examples of educational support. Simulators for training purposes, such as fright, navigation and engine-room simulators, have long traditions and their importance is obvious. However, not only simulators and games, but also other types of simulation offer good opportunities of training future professional skills and specific theoretical knowledge [3,27]. For example, rSle-play is a usual way of training students to express themselves in a foreign language, in different contexts relevant to their future profession. Designing information systems

The principle difference in describing, designing, and learning to use information systems, compared with other systems, is the level of abstraction. Simulation is specially helpful in making abstract concepts understandable. For this reason, it is somewhat surprising that the technique has been accepted rather late in systems development. Its use is proposed to test new systems, to learn to use them, and to improve them, if necessary, before they are finally implemented. The purpose of simulation seems to be to give system designers information for producing a system which better meets the needs of end-users. Thus, this kind of simulation in fact supports the work situation, although in a preventive way. The concept of simulation is here used as an equivalent to prototyping. "The discussion between a prototype and a simulation is really quite arbitrary since, for large appfications, it will probably be necessary to simulate some aspect of the use of any prototype, in order to allow the user to comment effectively."[16, p. 420]

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Alternatives to simulation, which might be used, are demonstration of corresponding systems and pilot systems. However, demonstrations do not offer users practical testing possibilities, and developing pilot systems is resource-consuming for large-scale systems. Including h u m a n factors in the software development process has been discussed [22] and for this purpose several types of simulation are suggested. Product mock-ups, using focus groups and arranging user studies in laboratories, are proposed. When a decision has been made on the design of a particular software product, a mock-up of what the product does is presented. Building product mock-ups means constructing a false user interface scenario and generating a videotape of it. These videotape mock-ups are shown to focus group participants and to the future users. The purpose is to test whether the appropriate user requirements have been specified and are met. However, these mock-ups can also be used for marketing. They can be shown to managers to demonstrate what is under development and to explain the product to potential investors and customers. User studies take place in a laboratory - - i n fact, in a model of the natural environment. The users are asked to perform their new tasks with the help of existing facilities--paper and pencil, calculators, and old computer systems, for example. This means simulating the would-be system. The purpose is to analyse task performance and to get a model of what users think of the tasks, before the system is finally designed. In the UTOPIA project [5], users not only participated, but in fact conducted the development project with the help of edp-professionals. To define the requirement specifications, a technology laboratory was established with tools to simulate the work to be done with the aid of the computerized system being developed. This environment and the tools were also helpful in teaching situations. The experimentation started with mock-ups, simple models of the tools needed, for example, a " w o r k station" with "high-resolution" display, built of paper, match-boxes and plywood. This equipment was used to create the screen images (drawn by hand) while the worker, step by step, performed the actual task with the help of the mock-ups. This way of getting started was reported successful; the workers could at once actively take part in the design process. The

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method was cheap and the experiments were not limited to available equipment. Later, the mockups were made more realistic. Also, a real computer work station was used to illustrate aspects difficult to simulate with mock-ups. Using real computer equipment helped the workers relate the mock-ups to the real applications that were planned. This approach allowed the workers to articulate their demands and wishes in a concrete way, by actually doing their work on the simulated equipment, which naturally made it easier for them to make themselves understood. In the AMIS project [10], "simulation" is used in two different meanings. First, there is the concept of "what-if simulation", which can be described as experiments where the consequences on work situations caused by changes in informations systems, are studied. Here, models of the planned changes in the information system are created. The approach gives an opportunity to compare the expected results with the recorded historical facts. Unexpected side-effects can also be detected. Selection of the model which best suits the current situation is facilitated by experimenting with alternative models and by testing their outcome against existing data. This kind of experimentation offers good opportunities for learning, both to edp-experts and to users of the systems. The approach is especially suitable for designing systems for use on trial. The other concept is "simulation of entire work situations". It consists of experiments with different w o r k organization, j o b contents a n d boundaries of responsibility, and investigates what demands these may put on the information system. While simulating concrete situations, users can show each other how they work and how they would like to work, they can tell about their wishes, stress their demands, and illustrate desired changes, using models which represent their ordinary work situation. This kind of simulation can be done with the help of computerized models, or manually. R61e-play, where the workers do not play their own working r61es but one another's (r61e-taking, to use an alternative concept) gives an excellent opportunity to learn to understand the importance of collaboration. Simulation of entire work situations is specially aimed at improving the work contents. Furthermore, it gives a broad understanding of the organization. The knowledge is obtained when models are con-

structed and during the simulation sessions, and is not dependent on whether the changes are realized. Learning to use information systems In the Knowledge and Work project [11], manual simulation was used to support users' learning. The concept included r61e-play, discussions, and manual simulation of the functions of the computer. The purpose was to enrich users' understanding of their information systems, thus enhancing the use situation. The goal was to help users look at their information systems as part of the work context, and therefore work and the supporting information systems were treated on an equal basis. Simulation sessions were arranged, in which persons from different departments participated. A model of the system which was studied was built and the flow of information and m a t e r i a l / products was simulated, but all this was done m a n u a l l y - - n o t computerized. W o r k tasks were illustrated by simulating transaction flows. The participants performed their ordinary tasks, but instead of using computers they had to communicate directly with each other. A manuscript for the simulation was composed in such a way that the n o r m a l / u s u a l transactions were carried out before r a r e r / e x c e p t i o n a l / e r r o n e o u s ones. For those acts where computer tasks were simulated, written lines were distributed to the "actors", but otherwise they could improvise. To present the IS and its functioning; it was dismantled into parts and converted to manual objects and acts: electronic files to card files, some important algorithms to rules written in everydaylanguage, and computerized functions to h u m a n actions. Of course, not all files were converted nor all records included, but entities from the most essential were. The edp-system was thus simulated manually. Simulation as a learning technique was evaluated by participants; they regarded it as useful for obtaining theoretical knowledge, although the technique as such was very concrete. Simulation was considered lucid, easy to understand, realistic and informative by more than 80% of them. Its usefulness was demonstrated by following positive attitudes (90%): it helped them to understand other workers' tasks and the information flow, and it

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clarified the meaning of the information used. Manual simulation of the computerized functions was evaluated as helpful (80%). However, the participants' attitudes towards playing r61es were more restrictive. To conclude the whole survey, we can notice that very little is documented about simulation used in training work situations. Simulation is reported to have been applied for user-training purposes only in the context of information systems development and use, and in educational programs. Mostly, it is treated as a mere aid in work.

Classification of the approaches One aim of this study was to answer the question of whether a rule for classification of simulation a p p r o a c h e s - - w h i c h type of simulation is used for what kind of p r o b l e m - - c o u l d be found. In Table 1, all applications mentioned are classified according to the simulation technique used. It is obvious that when talking about simulation, computerized simulation models dominate. Nevertheless, from Table 1 it can be seen that for training and education all types of simulation are used. Also in the context of systems development all but game simulations are used. However, this domain includes a lot of training, too. If it is possible to draw any conclusions at all from the previous examples, it would be the following: the

various techniques of simulation ae used mostly for training purposes.

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Evaluation of simulation As the survey part of this paper shows, different types of simulation have been applied to a wide variety of fields and purposes. Here, simulation in the context of systems development and use is evaluated from different perspectives. In systems development, simulation has shown to be effective in saving money (prototypes are simulations or mock-ups of the planned system) and in allowing users to take part in the development process of the system from the very beginning. User participation has improved the motivation to use and accept the new t e c h n o l o g y - - a n d in m a n y cases has given better functioning systems [1,17]. It can also diminish the discrepancy between users' and designers' cognitive models of the functions of the system [1,29]. This is important because the discrepancy between cognitive models will cause erroneous expectations by the user, impair learning and using the system, and make recovery from unexpected situations harder. Graphical simulation of a system gives a clear and easy-to-understand idea of the logical structure and functioning of the system [28], so that there is no need to interpret the results, The process is simply what you see. Simulation is also one of the best w a y s to concretize abstract things, which implies that real understanding of phenomena and tasks is improved. It is possible to create a very concrete picture of abstract concepts and relations between concepts, to show dynamically how variables change state, what happens in a process, and how

Table 1 Use of specific simulation techniques to support problem solving in different fields Computerized simulation models Complicated organizations Prognosis and prediction Analysis Control systems Physical systems Traffic systems Planning Macroeconomic processes D y n a m i c processes Process industry Training and education Systems development Use of information systems

R61e-play

Games

Simulators

Manual simulation

X

X

x X x

X X X X x X X x x

X X X

X

X X

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a program functions. In the Knowledge and Work project, manual simulation of a complex computer system was successfully used in teaching users the principles and functioning of the system [11]. Maps which show the structure of the program and users' actual position in the program at a given time, are effective performance aids in using programs [4,20]. Hands-off training on an abstract level of encoding gave as good results as hands-on training [9], when teaching the use of a business telephone system. These are examples of situations where users learned something of the principles of the system, not the actual use of the system on a superficial level (in which order the buttons ought to be pressed). This kind of approach makes the system more transparent; the user gets an idea of what is happening and why, and can generate an appropriate cognitive model of the system. It has been stated that procedural literacy, with the implied understanding of such concepts and principles as parametrized procedures, hierarchical program organizations with nested sub-routines, etc., is essential for everyone who wants to use computers effectively [25]. This kind of thinking strongly contrasts with the saying that the microprocessor is the most versatile and flexible thing ever found. We think that the majority of users are interested in the results of an action, not how the program reaches the result, and that is something which ought to be made obvious to them. We argue that learning the underlying processes of a program on an abstract level is a much more valuable learning goal than nested sub-routines or hands-on training of the actual use of the program. If, for example, the user understands what Copying and moving a block in a word-processing program means, he can refer to the manual or the on-line help system of the program and check how to proceed. But if the user does not understand the process, opening the manual at the right page can be difficult and even asking the right questions from a h u m a n advisor can be impossible. Users of intelligent help systems [7], in face-to-face advisory dialogues, had their hypotheses about what was happening in the program, proposed solutions and put questions concerning the results, asking how to achieve or avoid them. More transparent systems which show their users what really happens might be helpful in such situations. Even better learning effects could be reached, if users

could simulate a series of actions without affecting the real data.

Future views

The Knowledge and Work Research group is now doing research with the purpose of using simulation in a prototype model of a realistic information system. The prototype is aimed at giving the user information not only of the information system but of the whole working environment, including computerized as well as other work. The basis is the interface with its help facility. The user can choose simulation of an action and get an animated simulation of things happening both in the information system and in the working environment. The user can also look at the whole working environment and get answers to such questions as: " W h e r e are the boundaries of my responsibility?", " O n which parts of the organization do my actions on the information system have effect?", " W h a t kind of information is handled in another part of the organization?", and so on. This links the information work with other work and gives an idea of the organization as a whole. Our hypothesis is that this kind of help facility will not only facilitate learning, but also cooperation and work motivation, as a result of improved understanding of the whole situation. Use of simulation in user training can be improved and expanded when the available technical resources support this usage. W o r k stations and personal computers are becoming more powerful and new features are being added to them. For example C D - R O M systems give access to a vast amount of data, while graphical displays and tools lower the costs of animation. The new C D - R O M XA standard gives the possibility of both speech and video representation. This means that the proper tools for simulation and animation are near at hand. The following scenario is already a reality in the PC-environment and, hopefully, not so far away in the mainframe context either: " T h e tradition of presenting software and system documentation in businesslike, formal and dry prose is perhaps missing an opportunity to motivate users to pay attention. Perhaps a narrative story about a scenario of use

would be more intrinsically motivating than a list of

L Eriksson, P. Reijonen / Training computer-supported work by simulation key functions and their syntax. Perhaps this would lead to better learning and performance." [8, p. 23]

The prospect in our group is an interface where there is no separate help system, but where the program itself is the help system or simulation system. In other words, there is no option for help or simulation of an action, but the program itself functions as the simulation of the reality and the tasks it aims to clarify.

Conclusion Use of simulation in work situations was studied. It was noticed that, for educational purposes and for the design and use of information systems, several types of simulation techniques were reported to have been used. This might be interpreted in such a way that simulation is regarded as helpful for learning. Also, we propose simulation as a profitable way to train end-users to make efficient use of their information systems in their work. Simulation techniques make it possible to present abstract concepts and their connections in a very concrete way. In a systems design process, it is exactly this transition between abstract and concrete representation which makes end-user participation and also communication between users and edp-professionals, difficult. In a use situation, simulation can offer more comprehensive help facilities. The whole work situation can be described on both the organizational level and in detail, including computer-supported and manual information work as well as other work. Simulation m a y thus help in learning to use the system, in dealing with unusual and exceptional situations, and in tracing errors. A practical problem today is that it is rather laborious to design simulation and animation programs, but improved technology and programming environments will, in the future, provide new opportunities.

Acknowledgements We should like to thank Professor Aimo TOrn at Abo Akademi and Professor Markku Nurminen at the University of Turku for their valuable comments. Thanks are also due to Christopher Grapes,

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w h o helped with the revision of the English lan-

guage of the paper.

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