=Paper=
{{Paper
|id=None
|storemode=property
|title=Usability Evaluation of Method Handbook
|pdfUrl=https://ceur-ws.org/Vol-1028/paper-02.pdf
|volume=Vol-1028
|dblpUrl=https://dblp.org/rec/conf/bir/Heinermann13
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==Usability Evaluation of Method Handbook==
https://ceur-ws.org/Vol-1028/paper-02.pdf
Usability Evaluation of Method Handbook
Laura Heinermann1, Dirk Stamer1, Kurt Sandkuhl1,2
[1] Rostock University, Institute of Computer Science
Albert-Einstein-Str. 22, 18059 Rostock, Germany
[Laura.Heinermann, Dirk.Stamer, Kurt.Sandkuhl]@uni-rostock.de
[2] School of Engineering at Jönköping University,
P.O. Box 1026, 55111 Jönköping, Sweden
Kurt.Sandkuhl@jth.hj.se
Abstract. In enterprise modelling and information systems development, methods
contribute to systematic work processes and to improving the quality of modelling
results. Information Demand Analysis (IDA) is a method, which recently was
developed for the purpose of optimizing the information flow in the field of
information logistics. In order to contribute to improvement of the IDA method,
the focus of this paper is to evaluate the usability of the IDA method handbook.
For this purpose, an approach for usability evaluation of the handbook is proposed
and applied. The main contributions are (1) an approach how to apply the concept
of usability when evaluating a method handbook, (2) experiences from using this
approach in a real world case, and (3) recommendation for improving the IDA
method handbook with respect to usability.
Keywords: information demand modelling, method usability, information
logistics, practice of modelling
1 Introduction
In enterprise modelling and information systems development, methods contribute to
systematic work processes and to improving the quality of modelling results [1, 2] by
providing procedural guidelines and notations for representing modelling results [3].
Information Demand Analysis (IDA) is a method, which was developed for the purpose
of optimizing the information flow in the field of information logistics (see section 2).
In an effort to provide this method, the creators of IDA released a handbook – the
“IDA-User Guide” – that intends to provide guidelines and instructions for conducting
information demand analysis. Although the IDA method has already been applied in
several organisations, the usability of its handbook in fulfilling the intended purposes is
still questioned. In utilising the handbook as applied to a real world situation, we
examine the usability of the handbook from the view of a user and intend to contribute
to its improvement. In the following we use “IDA-User Guide” equivalent to the term
“Handbook”.
The research on usability evaluation of user-oriented products belongs to the most
productive areas of research in the field of information systems. This is most certainly
inevitable since the growth of technology cannot be separated from the dynamic of the
human factor, which demands the quality of use. Critical research is being conducted to
examine the soundness of the usability concept as well as the suitability of the
evaluation methods applied. However, these works deal more with the principles of
usability for software products and less with the usability of an analysis method in
information logistics, let alone in the area of information demand. The focus of this
work is the application of usability to a method handbook. Other approaches in this
area, like the SEQUAL approach [4], aim to evaluate the quality of methods on the
overall.
Furthermore, we performed a literature analysis regarding IDA. Few results were
found in the search of particular literature on the evaluation of IDA method. This
situation is understandable because the method for information demand analysis is still
in its preliminary stage. The only script that is found on this related issue is an
undergraduate thesis written three years ago by a group of students at Växjö University
[5]. The emphasis of their work focussed on the requirements and not on the usability of
the method. Their object of research was the previous version of the method handbook.
These factors motivated us to begin an initial work on the usability of the handbook
for information demand analysis. The main contributions of this paper are (1) an
approach how to apply the concept of usability when evaluating a method handbook, (2)
experiences from using this approach in a real world case, and (3) recommendation for
improving the IDA method handbook with respect to usability.
The remaining part of the paper is structured as follows: section 1 introduces the
background of this paper from the area of information demand analysis and information
logistics; section 3 discusses related work with respect to usability and the approach
used for usability evaluation of the handbook; section 4 contains the evaluation of the
IDA method handbook; and section 5 draws conclusions.
2 Information Demand Analysis
Accurate and readily available information is essential in decision-making situations,
problem solving and knowledge-intensive work. Recent studies show that information
overload is perceived as a problem in industrial enterprises [6]. An example of a
problem in relation to information overload is, in relation to different roles, to find the
right information needed for a work task [7]. It is expected that an improved
information supply would contribute significantly to saving time and most likely to
improving productivity.
The research field information logistics addresses the before mentioned challenge in
information supply. The main objective of information logistics is improved
information provision and information flow. This is based on demands with respect to
the content, the time of delivery, the location, the presentation and the quality of
information. The scope can be a single person, a target group, a machine/facility or any
kind of networked organisation. The research field of information logistics explores,
develops, and implements concepts, methods, technologies, and solutions for the
aforementioned purpose.
A core subject of demand-oriented information supply is how to capture the needs
and preferences of a user in order to get a fairly complete picture of the demand in
question. This requires an understanding of what information demand is and a method
for capturing and analysing information demand. The term information demand (section
2.1) and the method for information demand analysis (section 2.2) will be briefly
discussed in this section.
2.1 Information Demand
The understanding and definition of the term ‘information demand’ used in this paper is
based on an investigation performed from 2005-2007 [8]. The main objective of this
investigation was to identify the connection between information use and different
work-related aspects, such as work processes, resources, and organisational structures,
in order to achieve a better understanding of the term information demand. The
investigation comprised 27 interviews with individuals from three different
organisations, a sample which represented all levels of the investigated organisations,
i.e. from top-level management via middle management down to production- and
administrative personnel. Among the results of the investigation was a definition of
information demand as well as a conceptualisation of this term. Information demand
will be used throughout this paper with the following meaning: “Information demand is
the constantly changing need for relevant, current, accurate, reliable, and integrated
information to support (business) activities, when ever and where ever it is needed.”[8]
Information demand has a strong relation to the context in which such a demand
exists [8]. The organisational role having the demand and for what task the information
is demanded as well as the setting in which such tasks are performed are important
aspects for understanding information demand. Thus, the concept of information
demand context has been defined both conceptually and as the core of the method with
respect to modelling, evaluating and analysing of information demand: “An Information
Demand Context is the formalised representation of information about the setting in
which information demands exist and comprises the organisational role of the party
having the demand, work tasks related, and any resources and informal information
exchange channels available, to that role.”[8]
Based on the above results, a method for analysing information demands and
capturing information demand context has been developed as part of the research
project infoFLOW-2 during 2010 – 2012 [8]. This method is documented in a method
handbook, which describes the work procedures to be performed, the notation for
documenting information demand contexts, and the concepts and aspects to be taken
into account during analysis. The different phases of this method will be introduced in
the next section.
2.2 Method for Information Demand Analysis
In Figure 1 an overview of a framework for achieving such an understanding is
presented, which will be described in this section. Since context is considered central to
information demand analysis, method support for modelling such contexts is at the core
of the framework as highlighted in the framework below. However, in order to be able
to perform any meaningful context modelling, a clear scope is needed. Consequently,
the information demand analysis starts with scoping activities.
Figure 1: An overview of the process of analysing information demand
Scoping is the process of defining the area of analysis and is done with the purpose of
selecting parts of an organisation to be subjected to analysis. This phase also includes
the identification of the roles (individuals) relevant for the continued information
demand analysis. Scoping also sets the scene for identification and understanding of the
organisation’s problems, goals, intentions, and expectations to motivate them to engage
in the information demand analysis.
Information Demand Context Modelling is mainly performed through participative
activities such as joint modelling seminars where the participants themselves are
involved in the actual manufacturing of different models. This process is usually
supported and facilitated by a method expert who could be an internal or external
person. As illustrated in Figure 1 the conceptual focus is in this phase of information
demand within a defined scope. The key to context modelling is to identify the
interrelationship between roles, tasks, resources and information. No regard is given to
the sequence of activities, resource availability, etc.
Information Demand Context Analysis and Evaluation: Once the necessary
knowledge about the information demand contexts is obtained, it can be used for a
number of different purposes. One purpose is evaluation where different aspects of
information demand can be evaluated in relation to roles, tasks, resources and
information. It is also suitable to address the results from the modelling session with
respect to motivation and purposes expressed during the scoping activities. Focusing on
information demand contexts provides only an initial view of information demand
without any consideration given to such aspects as individual competence,
organisational expectations and requirements in terms of goals, processes etc.
Depending on the intentions behind the analysis further activities might be required.
The method provides a number of method components supporting such activities. Since
the main focus of the method presented here is on information demand, it utilises
existing procedures and notations for such additional aspects rather than defining new
ones. Consequently, if the method user wishes to investigate such additional aspects of
information demand, he or she can do this by using subsets of the other methods,
notations and languages.
3 Usability Evaluation Approach
In this section the approach taken to arrive at a suitable definition of the term usability
in the context of the IDA User Guide is described. In addition, the proposed criteria for
usability evaluation are outlined. Therefore, in section 3.1, Usability in the context of
evaluating a handbook is defined. In section 3.2 the given definition is evolved into
Evaluation Criteria.
3.1 Approach to defining Usability
The daily use of the term usability is often found reducing the meaning of the word
simply to be the ease that one has in using a product. However, the dimensions of ease
itself are so diverse that it is quite difficult to measure. Usability practitioners in the area
of Human Computer Interaction have dealt with this situation since the early 1970s.
During the course of usability research in the field of software engineering back in
1994, usability practitioners had complained that work on usability was too little, too
late. Nigel Bevan believed that the reason for this complaint lay in the narrow view
toward the term usability. Usability was often considered only in the term of ease of use
while the term of ability to fulfil its intended purpose was neglected [9, 10].
Owing to the experiences of fellow usability researchers from the field of information
systems, we are well aware of these important aspects of usability and are, therefore,
taking these aforementioned aspects into consideration in our initial work on evaluating
the usability of the IDA User Guide. Realizing the different contexts between that of
software engineering and that of information demand, our attempt to determine a
suitable definition of usability for this work is directed in approaching the interpretation
of usability based on the context of use.
This approach is believed inevitable due to the absence of previous research on defining
usability in the practical use of method to the best of our knowledge. Here we observe a
definition of usability from a usability practitioner and anticipate how usability is
interpreted by the International Organization for Standardization.
Jakob Nielsen defined usability by associating it with the following five attributes:
• Learnability: The system should be easy to learn so that the user can rapidly
start getting some work done with the system.
• Efficiency: The system should be efficient to use, so that once the user has
learned the system, a high level of productivity is possible.
• Memorability: The system should be easy to remember, so that the casual user
is able to return to the system after some period of not having used it, without
having to learn everything all over again.
• Errors: The system should have a low error rate…catastrophic errors must
not occur.
• Satisfaction: The system should be pleasant to use, so that users are
subjectively satisfied when using it [11].
The International Organization for Standardization issued ISO 9216 from 2001 to 2003
as the series of standards addressing software quality and replaced it by ISO/IEC 25010
in 2011. To understand the implicit value of usability beyond the applied categorization,
we will consider both releases of the standard for our observation.
ISO 9216 constituted a software quality model which divides software quality into six
general categories of characteristics: functionality, reliability, usability, effectiveness,
maintainability and portability. Simultaneously the definition of usability is given as
“the capability of the software product to be understood, learned and liked by the user,
when used under specified conditions” [12].
In the final draft ISO/IEC FDIS 25010 a quality-in-use model constituted five
characteristics whereas three of them, which tend to be relevant for our purposes are
presented here with their definitions as follows:
• Effectiveness: accuracy and completeness with which users achieve specified
goals.
• Efficiency: resources expended in relation to the accuracy and completeness
with which users achieve goals.
• Satisfaction: degree to which user needs are satisfied when a product or
system is used in a specified context of use.
• Freedom from risk
• Context coverage.
Effectiveness and Efficiency are not further divided into sub characteristics as
Satisfaction is. However, we believe among the given sub characteristics of Satisfaction,
Usefulness is the only one applicable to our context. It is interpreted as “degree to which
a user is satisfied with their perceived achievement of pragmatic goals, including the
results of use and the consequences of use” [13].
The concept of Usability was still recognized in the development of the standard and the
characteristic Usability is categorized as one of the characteristics of the second quality
model - product quality model. It is stated as “degree to which a product or system can
be used by specified users to achieve specified goals with effectiveness, efficiency, and
satisfaction in a specified context of use” with the sub characteristics: appropriateness
recognisability, learnability, operability, user error protection and user interface
aesthetics [13].
In both releases, Usability is to be associated with the perspective of learnability,
specified user, specified goal and specified conditions or specified context of use. In
addition, the presented quality of use model indicates the human factor approach, in the
sense that the system is able to fulfil the needs of the user. Both aspects seem to be
maintained as the backbone of the definition of usability in the past two decades.
These aspects of usability are now to be assessed with respect to their compliance with
the nature of the handbook and the context of information demand analysis to which the
handbook refers.
1. Learnability: the system should be easy to learn so that the user can rapidly start
getting some work done with the system.
As stated in the outline of the handbook, section Background, “a method of information
demand analysis therefore has to include all relevant aspects of enterprises, such as
work tasks, organisational structures, processes, information sources and information
receivers. This handbook describes exactly such a method in terms of content, structure,
and use.”[8] Consequently a holistic understanding of the content, structure, and use of
the method is very important. Moreover, learning a concept, which is intangible unlike a
visualized program, requires a very clear explanation and understandable description
from the provider of the concept. Taking these matters into consideration, the
comprehensibility of the handbook is an essential aspect for the usability of the
handbook. Therefore, the term learnability is going to be replaced with the term
comprehensibility and its interpretation is as follows: the handbook should be easy to
understand so that the user can quickly perceive the overview of the method and finish
the preparation for the analysis in a timely manner.
2. Specified user.
In the section Purpose of the Handbook, there are three different types of readers the
handbook is intended for. This differentiation is nonetheless not a specifying
classification based on some competency requirements in the area of information
demand analysis. It is rather to serve as information about the particular intentions the
handbook is able to facilitate. Since the IDA method itself is “user-intensive”, the aspect
of user should be adopted in the concept of usability of the handbook. However, the
term “specified” is not proper in this case due to the abovementioned view and will be
dropped therefore.
3. Specified goal.
Accommodating different types of user requires the handbook to be able to
accommodate their different goals, which can be found within the stated purpose of the
handbook. The specified goal refers to that of the user in using the handbook according
to its stated purpose. Based on this view, this aspect of specified goal is relevant for the
concept of usability of this handbook.
4. Specified context of use.
The Handbook described in the section The Purpose of a Method for Information
Demand Analysis the context in which information demand analysis needs to be done.
Hereby the context of use for the handbook is already specified and a specified context
of use is not relevant for the usability of the handbook.
5. Effectiveness in the sense of accuracy and completeness with which users achieve
specified goals.
The specific purpose of this handbook is to facilitate the information demand analysis.
Consequently, the focus of the handbook is placed on the pragmatic aspects of
information demand. Owing to this purpose, accuracy and completeness of the
explanations, directions and references in the handbook is very important. Although it is
somewhat subjective, it is absolutely relevant for the evaluation of quality of use.
6. Efficiency as in resources expended in relation to the accuracy and completeness
with which users achieve goals.
The amount of resources required for the implementation of the handbook depends on
various factors. Amongst them are the user profile, the perceived problem, and the
context of the use. Even if the resources used can be recorded and the procedures
repeated, there are still more variable parameters than fixed ones in the implementation
of the handbook. A further specialization in the area of implementation would probably
be necessary before integrating this aspect into the usability of the handbook. Hence, we
find this aspect irrelevant for the consideration of current usability of the handbook.
7. Usefulness with respect to the degree to which a user is satisfied with their
perceived achievement of pragmatic goals, including the results of use and the
consequences of use.
The practical steps found in the fourth section of the handbook are categorized into
prerequisites, activities and expected results. The expectation and pragmatic goals of
user during each of these steps can hereby be evaluated regarding to the usefulness of
the prerequisites, activities and expected results of each phase. Therefore usefulness is a
relevant attribute for the concept of usability.
Under the consideration of the abovementioned analysis, we define the term usability of
the handbook for Information Demand Analysis as follows:
The quality of the handbook to be used with comprehensibility to achieve the specified
goal with accuracy, completeness and usefulness for the user.
3.2 Evaluation Criteria
By using the building elements of the before given definition we are going to propose
criteria for evaluating the usability of the handbook.
Attributes
Among the said elements there are four attributes, which are directly related to the
quality of use of the handbook. These attributes are as follows:
• Comprehensibility: the handbook should be easy to understand so that the user
can quickly perceive the overview of the method and finish the preparation for
the analysis in a timely manner.
• Accuracy: the essential point is communicated in the right section and each
section presents its contents according to the correct priorities.
• Completeness: all the essential features are available. The pertained
explanatory elements are likewise obtainable.
• Usefulness: the conceptual as well as practical descriptions available in the
handbook do not only meet the user’s fragmental expectations, but also
accommodate the user’s pragmatic goals.
Selected Criteria
In evaluating these attributes, certain criteria or parameters for the analysis are needed.
There are certainly many facets pertaining to those attributes, but for this work on this
particular handbook for information demand method, we limit our list of criteria. Based
on our apprehension of the handbook, we assign the abovementioned attributes into the
following aspects:
• Wording. It is one significant factor of comprehensibility in an expositional
text such as a handbook.
• Contextual and visual illustration of the concept. Similar to wording, the
contextual and visual illustration is also an influential factor of
comprehensibility.
• The stated heading of each section and the main idea that emerges in the
respective section are coherent to each other. This can serve as an aspect to
evaluate the accuracy of the handbook.
• No parts of ideas, important notes or description pertaining to the existing ones
are missing. This is an aspect of completeness.
The results of use after each phase meet the user’s expectation and her or his goal. This
is an aspect of usefulness.
We proposed here several attributes and selected criteria to evaluate the IDA User
Guide. Due to the explorative advance we did not develop a measurement scale. This
would be a further step towards applying usability concepts to a handbook.
4 Case Study and Evaluation of IDA User Guide
Most research projects conducted in university are financed by external funders, who
make their decision to grant the fund or not based on the competitiveness of the
submitted proposal for the respective project. The process of writing this proposal
involves a great deal of information to be processed and procedures to be conducted by
various areas of responsibility within the university. The information demand within
this information-intensive process of proposal writing is to be identified with the
method described in the handbook for information demand analysis. Our customer is the
head of the proposal writing team. Interviews are conducted with the head of the
proposal writing team, the financial administrator of the institution and the content
manager. Furthermore, the role of method user is defined as the method-applying person
who does the interviews as well. Problems that arose during the implementation of the
handbook are recorded along with the evaluation of the usability criteria.
The following sections are structured according to the process of analysing information
demand. Within the sections stated activities (proposed by IDA user guide), performed
activities and problems, which occurred, are listed.
4.1 Scoping Phase
Stated activities
• Understanding and identifying the perceived problem.
• Defining the problematic area and the actors within it.
Activities performed
• Orientation interview with the head of the team about the process of proposal
writing to get a basic understanding about the process.
• Prepared a mission statement with input from the interview.
• Review of the mission statement by the head of the team.
Problems
• Difficulties in describing the mission statement, especially the description of
expected results and effects of the assignment by a misunderstanding.
4.2 Information Demand Context Modelling Phase
Stated Activities
• Short semi-structured interviews with each of the selected individuals in order
to get an understanding of their expectations, goals and problems.
• Modelling seminars to collect the needed information to perform further work
with the aim to get the participants to identify the different tasks performed
within the scope and how this relates to information which is needed or used,
grouped by role. Typically, this is done by writing down different tasks and
information objects on pieces of paper and attaching them to large paper or
plastic sheets and then connecting them to each other. The reasoning and
motivation behind this approach is that it allows for easy restructuring and
changes as the session progresses. An additional benefit of such a non-
technical approach is that is easier to get the participants to contribute to the
emerging model than it would be if they all were seated around a table
watching the model emerge on the facilitator’s computer screen.
Activities performed
• The first inquiry session was conducted with the head of the team. This lasted
15 minutes longer than the estimated duration of 60 minutes.
• For the session with the financial administrator, a sample of the model
adopting the illustrated sample case was prepared with the same modelling tool
that will be used for the interview. This sample was then shown to the
informant at the beginning of the session. The reason for this was to provide
the informant a better picture of what the result of the session was supposed to
be. This sample was in German as to accommodate the preferable language of
the informant for the session. The duration of this session was exactly as
estimated.
• For the session with the content manager, the sample of the model was again
shown to the informant at the beginning of the session. In spite of the use of
the German sample, the language for the session was English. This session also
finished within the estimated time.
Problems
• During the first session there were problems to classify the statements and
responsibilities given by the informants.
• Regarding the respect to all three sessions: The first stated purpose was not
fulfilled. The method user does not understand the character and personality of
the individuals. Method user had difficulties identifying the information within
the information situation.
4.3 Analysis and Documentation of Information Demand Phase
Stated Activities
• Transcription of the initial models into well-defined notation.
• During the transcribing of the models correlations between information flow in
the current case and information flow in the previous cases can sometimes be
identified. If an identified situation within the models is considered similar to
already identified and solved situations from other cases it is reasonable to
assume that the solutions applicable in that situation are also applicable in the
current one. If no corresponding pattern can be found in the pattern collection
despite the fact that it has been identified in a number of different cases, it is
reasonable to assume that a candidate for a new and valid pattern has been
identified.
Activities performed
• The models out of the first interview and modelling sessions were still lacking
in connectors to most of the relationships. These three models were then
analysed using the information from the documented interview.
• Constructing one new overall model out of all three, bilingually.
• To fill the gaps and get a confirmation for this developed model, a second
meeting with each informant was then scheduled, which leads to their approval
to the model. Furthermore, a similar information demand pattern addressing
the process of proposal writing was found in the collection of patterns. Based
on this pattern, the approved context graph was then digitalized.
Problems
• During transcription some flows were unclear because of the different
treatments to the type of information. This should be described more clearly in
the handbook.
5 Conclusions and Future Work
As shown in section 3 the concept of usability was applied, when evaluating a
method handbook. The starting points were definitions of usability given by
practitioners and the International Organization for Standardization. We extracted and
analysed the relevant terms from the definitions. As a main contribution an adapted
definition of usability for the Information Demand Analysis User Guide is proposed as
the quality of the handbook to be used with comprehensibility to achieve the specified
goal with accuracy, completeness and usefulness for the user. Furthermore we proposed
evaluation criteria to measure the given attributes in the definition. Due to the
explorative advance we did not develop a measurement scale. This will be a further step
towards applying usability concepts to a handbook.
In section 4 we applied this approach in a real world case. This quality of use was
evaluated by implementing the handbook in an information-intensive process within the
process of proposal writing in the university. This leads to helpful insights and practical
guidance in the internal process. Through its implementation, the information situation
within the process of proposal writing became clearer, and suggestion for solving the
problem related to information demand could be given. By using the definition of
usability approached in this work, a continuation of the evaluation process in the future
is possible.
Although the method user handbook follows in most aspects the usability
requirements, but as another contribution some recommendations for improving the
IDA method handbook with respect to usability could be given:
• Important notes on the procedures of asking questions during the interview.
• Additional explanation of the contextual use of identifying and differentiating.
This work attempted to apply one possible concept – usability – to improve the quality
of a method handbook. As a further approach knowledge from cognitive psychology
could be integrated as well.
The results of this usability evaluation may contribute as well to the acceptance of
the Information Demand Analysis method in the networked organization and to the
improvement of its quality.
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