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    <article-meta>
      <title-group>
        <article-title>Evaluating Socio-Technical Systems with Heuristics - a Feasible Approach?</article-title>
      </title-group>
      <fpage>91</fpage>
      <lpage>97</lpage>
      <abstract>
        <p>In the digital world, human centered technologies are becoming more and more complex socio-technical systems (STS) than in previous years thus challenging existing traditional design and evaluation methods. There are two new tendencies, a) STS-methods for design and development are complemented by methods for evaluation of existing STS, and b) the question arises on how to evaluate STS and their quality sufficiently. In this paper we illustrate a method to develop STS heuristics combining four differed areas of research: CSCW, job design, usability heuristic and socio-technical design principles. Initial results will be presented and discussed.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>Over the past years, human centered technology and socio-technical projects have
emerged that challenge existing evaluation methods. Project examples are wearables in
health care, remote service systems for older adults, applications of cyber physical
systems and others. A major part of those design projects is their evaluation. This part of
the design process is especially crucial since it becomes more and more evident that it
is not possible to plan all aspects of complex socio-technical systems (STS) in advance.
Those systems rather require a mutual adaptation process between technology and the
context they are used in [1–3] which requires suitable methods of evaluation.</p>
      <p>
        Usability testing is a well-established procedure
for evaluating interactive systems in this context and
a variety of evaluation methods has been developed
in the past. Within these methods, heuristics have
become a recognized approach to identify usability
problems. Heuristics can serve as a basis of cognitive
walkthroughs where experts inspect the features of
an interactive system step-by-step. Typical heuristics
like the ones by Nielsen (c.f. Fig. 1) or by the
International Standard Organization (c.f. ISO 9241-110,
2006) cover aspects such as the suitability of a
system for a task, its controllability, individualization,
self-descriptiveness, conformity with user expecta- Fig. 1. Usability Heuristics
actions, error tolerance, and suitability for learning. cording to Nielsen [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]
      </p>
      <p>In this contribution, we argue that it is useful to employ heuristics also in order to
evaluate STS. This however requires existing usability heuristics to be revised or
adjusted in order to cover the much broader context of STS. While usability issues are
focusing mainly on human-computer-interaction (HCI) and individuals, STS are more
complex systems in the sense that they involve HCI and team work which is mediated
by technology. Consequently, our research questions are: To what extent and in which
ways can existing heuristics be used for evaluating STS? Are there any aspects missing,
and if yes, how should existing heuristics be revised towards ‘STS heuristics’?
2</p>
    </sec>
    <sec id="sec-2">
      <title>Contextualizing the evaluation of STS – From Usability to</title>
    </sec>
    <sec id="sec-3">
      <title>STS Heuristics?</title>
      <p>
        Heuristic-based evaluation can be considered a formative evaluation method [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] that
helps to identify which properties of a system are likely to hinder its success by meeting
the interest of involved stakeholders. However, while it is almost always possible in the
context of usability testing to test all possible dialogue sequences using a prototype
(e.g., interfaces, displays), this is not possible in the case of STS since the variety of
potential work processes (e.g., workflows, job activities) cannot be tested completely
due to them being planned or conducted in the domain of organizational and technical
change [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. The complexity of STS and diversity of workflows indicate that existing
usability heuristics might not be sufficient in order to evaluate STS. This ‘heuristics
gap’ becomes obvious when considering well-known principles of socio-technical
systems such as those discussed by Cherns [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ], Clegg [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], Fox [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], Mumford [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] or Fischer
&amp; Herrmann [3]. These principles are primarily focused on the design phases of STS
and consequently cover aspects of how an STS could be developed in order to meet the
interests of current and future actors and stakeholders of that system. These
empiricallybased principles include requirements such as “the needs of the users have to be
understood”, “The core processes must be taken into account”, “the interests and their
interplay have to be analyzed”, “allow for participation of the relevant stakeholders” and
others. When comparing these STS principles and requirements to usability heuristics
such as the ones illustrated in Fig. 1, we immediately see the difficulty of finding an
appropriate level of description. This difficulty indicates that there is a need for
different kinds of heuristics or for revised versions of existing heuristics.
      </p>
      <p>
        Before we discuss the idea of how to study STS heuristics during the course of the
next section, we first want to describe an STS design and development method in order
to illustrate the complexity of STS design. Different approaches of user experience,
human-centered and socio-technical methods exist in order to make sure that an STS
contributes to the needs of social groups and end users. Since, in the usability context,
heuristics are regularly used in the context of walkthroughs (c.f. cognitive walkthrough
[
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]), we focus on the method of the socio-technical walkthrough (STWT) which is
characterized by Herrmann [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. This method consists of a series of facilitated
workshops where a group of selected stakeholders are supported by a facilitator to discuss
features of socio-technical processes by inspecting diagrams which represent typical
scenarios of a socio-technical process. These diagrams combine three phenomena in
order to arrive at an integrated description of the current or future processes within a
socio-technical system:
1. The communication and collaboration between people taking roles as they are taken
and developed in organizational contexts.
2. Human interaction with computer based systems which are used for task handling
and as a means of communication.
3. The technical infrastructure and the interplay between technical components.
      </p>
      <p>The STWT has been mainly applied to support the design and development of
sociotechnical solutions. Therefore, each walkthrough is guided by questions such as “which
information is needed here”, “which activity must or can follow here”, “which roles
should be involved” etc. We propose to use heuristics as a method for evaluating STS.
These methods can be based on revised versions of existing usability heuristics.
3</p>
    </sec>
    <sec id="sec-4">
      <title>How to develop appropriate heuristics?</title>
      <p>In principal there are two ways to revise existing heuristics and develop new ones:
1. A survey with experts can be conducted by asking them about the most crucial
problems occurring in the context of STS to their knowledge. These problems can then
be used as a basis for statistical analysis in order to derive a comprehensive set of
heuristics.
2. We can build upon existing heuristics, guidelines or principles and refer at least to
certain aspects of socio-technical systems. These can then be transformed into
intuitively understandable criteria which can be applied to STS.</p>
      <p>We argue for starting with the second approach, since
1. It is not possible to identify a suitable amount of experts that focus on STS as a
coherent whole since they are mainly focused on selected aspects such as job design,
usability, coordinative issues etc.
2. There are already a lot of existing heuristics which can be used as a basis.
3. Extensive studies to collect data and heuristics on a statistically secured basis is not
possible when one copes with new technologies such as big data, cyber physical
systems, crossactionspaces, mixed reality etc.
We propose to take heuristics into account which can be derived from various areas and
disciplines. It seems particularly promising to select established principles that cover
relevant aspects of STS. They possibly have to be transformed or reformulated to serve
this purpose. We strive towards heuristics that may be phrased in a way either to be
applied to</p>
      <sec id="sec-4-1">
        <title>1. real life phenomena (e.g., Ebay, LinkedIn, …),</title>
        <p>2. to representations of potential processes which correspond to STS (c.f. Fig. 2),
3. to a combination of both.</p>
        <p>For applying heuristics in a walkthrough we can use representations such as the one
shown in Fig. 2 which depicts an overview of a process where elderly people can order
a service which supports them during their weekly shopping. The original diagram
showing the details to be taken into account is much more detailed and contains about
123 activities (c.f. [2] for more details on about the case to which the diagram is to).
4</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Identifying areas from which to draw STS heuristics</title>
      <sec id="sec-5-1">
        <title>We propose following areas as relevant:</title>
        <p>
          1. Socio-technical design principles: This kind of principles are widely discussed by
Cherns [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ], Clegg [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ], Eason [
          <xref ref-type="bibr" rid="ref13">13</xref>
          ], Fox [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ], and Mumford [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ]. Cherns’ principles,
which are grounded in the work of the Tavistock Institute, play a leading role in
this discussion. A typical example of the principles discussed is: “minimal critical
specification of rules”. Principles like these have to be made concrete in the form
of heuristics such as “Are strict sequences of activities only prescribed if necessary
or logically indispensable?” or “Can the actors freely decide between a set of
possible tools which one they will use for carrying out a task?”. In the diagram depicted
in Fig. 2 sequences are sometimes explicitly left vague. Activities are instead
embedded into higher level activities which shows that they are part of these activities
while leaving their sequence open (such as “modify service on demand” or “bundle
orders”). On the other hand, a principle such as “core processes should be
integrated” [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ] can hardly be transformed into heuristics since its application would
require more extensive knowledge about the context of an organizations´ processes.
This knowledge is hard to include into an artefact or into prototypical situations to
which the heuristics should be applied.
2. Principles of Job Design: In the context of socio-technical design, Mumford [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ]
emphasizes the need for principles of job-design, such as knowledge fit,
psychological fit, efficiency fit, task structure fit or ethical fit. There are also other sources
for job design criteria such as the ones proposed by Hackman and Oldham [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ].
They consider the following criteria as influential: Skill variety, task identity, task
significance, autonomy and feedback. Once again the question arises whether
heuristics can be derived from these criteria which can be applied to a phenomenon
being the object of an STWT. Mumford’s “Knowledge Fit” and Hackman’s &amp;
Oldham’s “Skill Variety” require that necessary skills and knowledge are somehow
perceptible during the STWT. Consequently, it is necessary to provide
representations of the competences being required by the activities of a socio-technical
process. If they are displayed in diagrams such as shown in Fig. 2, a heuristic could be
phrased such as: “Does the set of task which are assigned to a certain role require a
variety of skills?” Other principles, such as Mumford’s “ethical fit” are hard to take
into consideration during an ex-post evaluation but have to be met during the
development and evolution of STS.
3. Usability heuristics: The most prominent usability heuristics have been proposed
by Nielsen [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ] although Tognazzini [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ] provides a more detailed list which
includes aspects such as offering appropriate colors or using feasible metaphors in
dialogues. Obviously, the more abstract heuristics are, the better candidates they
are to be transformed for the purpose of STS-evaluation. “Visibility” for example
requires that a user of a system can generally understand what is going on. This can
be easily transferred from the realm of human-computer interaction to a workers
socio-technical environment. Visibility in a socio-technical environment does not
only require feedback such as “Can the actors realize how their contributions effect
their environment”, but also includes information about the options for activities
which are available at a certain moment. Also “documentation and help” is an
interesting candidate since it is relevant on the level of organizational procedures and
not only for human-computer interaction – and can be closely connected to
learnability (see ISO 9241-110 or Tognazzini [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ]). For STS evaluation, it becomes
obvious that taking the area of usability into account adds new aspects which are on a
more concrete level than those in the context of socio-technical design principles
as discussed before.
4. Principles for the design of computer supported cooperative work (CSCW):
Applying the usability perspective limits STS evaluation since this perspective is
mainly related to individuals interacting with a computer. By contrast, the
discussion of socio-technical principles focuses on team/group work and the related social
aspects. Therefore, it is reasonable to refer to approaches which extend usability
aspects to the level of CSCW. Herrmann et al. [
          <xref ref-type="bibr" rid="ref17">17</xref>
          ] provide a set of heuristics which
are transformed to the group level. For instance, “visibility” is also extended to a
requirement which takes the awareness for the activities of others into account. The
aspect of “controllability” is phrased in a way that takes into account that the
autonomy of one actor might restrict the autonomy of another actor. Consequently,
on the level of an STS-heuristic, the new heuristics would scrutinize, whether the
system provides communication channels and routines with which the autonomy of
various actors can be balanced, e.g. by means of negotiation. Another approach by
Baker et al. [
          <xref ref-type="bibr" rid="ref18">18</xref>
          ] focuses on mechanics of collaboration and mainly requires suitable
communication support such as “Provide means for intentional and appropriate
gestural communication”. Another one of their guidelines, “Provide protection”, aims
at avoiding to lose a user’s work results. This is more appropriate on the
sociotechnical level e.g. by asking: “Are there routines ensuring that work results cannot
be overwritten, neglected or destroyed?” Additionally, it can be helpful to consider
coordinative issues [
          <xref ref-type="bibr" rid="ref19">19</xref>
          ] and requirements which have been elaborated in the
context of designing workflow-management systems.
5
        </p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>Next steps and Further challenges</title>
      <p>
        It seems to be achievable to compile a promising set of heuristics which can be
applied in walkthroughs to evaluate representations of socio-technical systems. However,
it is still an open question, how this list can be made consistent and how a short list of
the most prominent candidates can be extracted. Nielsen’s [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ] approach to arrive at
suitable usability heuristics was to prioritize them so that with a small set of 10 items a
large percentage of the most urgent problems can be identified. To pursue the same
goal with a set of socio-technical heuristics it would be necessary to evaluate them in a
number of projects, in order
 to see whether they help to identify problems which are considered as crucial by
experts,
 and to check whether it is possible to prioritize them in a way which can lead to
general validity.
      </p>
      <p>Furthermore, it is necessary to clarify how people that will use those heuristics have
to be prepared. This would require an understanding of who will be the potential users
and addressees of the heuristics. Potential users can be project managers or change
mangers, software-engineers, quality assurance people, researchers, but also the
workers or customers who are active within a socio-technical process. They have to be
trained to understand the heuristics and how they have to be applied during an
evaluation, since it is not just about giving a rating whether certain criteria are fulfilled or not
but to note potential problems so that they can be verified and potentially solved.</p>
      <p>A crucial challenge is that a socio-technical evaluation requires much more
contextual knowledge than it might be the case with pure usability testing. Thus the question
is how far it is necessary to somehow make the relevant context available or whether it
is possible to judge a socio-technical solution from an outside perspective. Probably it
is necessary to include several evaluators of whom some are coming from the context
of the system that is to be evaluated and others provide a less biased perspective from
the outside. Finally, since it is likely that multiple evaluations will take place during the
course of an STS project, heuristics have to be easily applicable still yielding sufficient
information to inform the STS project.
6</p>
    </sec>
    <sec id="sec-7">
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