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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Problem drift: a risk model for complex socio-technical pro jects</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Silvana Costantini</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jon G. Hall</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Lucia Rapanotti</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>The Open University</institution>
          ,
          <country country="UK">UK</country>
        </aff>
      </contrib-group>
      <fpage>47</fpage>
      <lpage>54</lpage>
      <abstract>
        <p>Increased globalisation and market volatility put pressure on organisations to become more exible and explore new technologies and operational domains, so that projects are becoming more complex, with increasing uncertainty and risk. Complex project management is challenging for both traditional and agile approaches: traditional techniques may be left behind by unrecognised environmental change in a volatile context, while in a stable environment, agile may require too expensive interaction with the client. One area of growing interest is how traditional and agile may combine to increase the chance of project success. Yet how to strike a balance between the two remains poorly understood. In this position paper, we propose a model for complex socio-technical projects related to risk arising from volatility, that tries to explain the balance of agile and traditional. The model introduces the concept of drift rate as a measure of volatility, with the impact of drift related to loss of development resource, risk accumulation as a function of resource expenditure and drift rate, and validation the means to manage that risk.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>Organisations must adapt to their changing business environment to remain
pro table, competitive and able to meet their strategic goals. In large
organisations, projects are the instrument of choice for such adaptations, each project
addressing speci c organisational socio-technical problems. Increased
globalisation and market volatility are putting pressure on organisations to become more
exible and explore new technologies and operational domains, so that projects
are becoming more complex, with increasing uncertainty and risk.</p>
      <p>
        There are many sources of complexity and uncertainty. From a technical
perspective, they stem from the combination, interactions and inter-dependencies
of technologies and the pace of technical change [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]; from a social perspective,
from \the number and diversity of stakeholders in the social network around a
project" [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], their culture and power relations; and, from a knowledge
perspective, the embedded, distributed and tacit nature of knowledge [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] combined with
inherent `wicked' [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] features prevents complex problems from being entirely
speci able upfront. Moreover, the volatility of the external environment, a key
driver for organisational change, accelerates and magni es complexity and
uncertainty [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. All combine to increase risk and failure associated with projects
[
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
      </p>
      <p>
        At a fundamental level, all project management approaches, whether
traditional (`plan-driven') or `agile,' seek to control uncertainty and manage risk,
while making best use of resources. Complex projects are problematic for both
approaches: environment volatility is a challenge for plan-driven ones, technical
complexity for agile ones, and knowledge complexity for both. While often
considered as antithetic, plan-driven and agile practices are increasingly combined
in practice, particularly in software development, in an ad hoc manner to reap
their bene ts, with various degrees of success [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]: the reality is that in complex
projects deviations and failure rates remain high [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>
        [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] advocate that complex project management should be seen as a form of
complex problem solving. This is also our position, therefore we apply a complex
problem solving framework to explicate and model features of traditional and
agile approaches. The framework is particularly strong at process modelling [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ],
and this allows us to consider their potentially constructive combination, indexed
by organisational and problem characteristics.
      </p>
      <p>
        The ultimate aim of the work is to equip organisations with the tools to
understand better the nature of their problems and tailor their project
management practices to their needs and culture. This position paper is a step towards
this aim: it seeks to explicate risk characteristics of project management
approaches when interpreted as problem solving processes, through the lens of
a design theoretic framework for complex problem solving, called Problem
Oriented Engineering [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Speci cally, we propose a model to explicate how di erent
approaches contribute to risk accumulation and mitigation.
2
      </p>
    </sec>
    <sec id="sec-2">
      <title>Risk and uncertainty</title>
      <p>
        The Project Management Institute's PMBOK de nes risk as \an uncertain event
or condition that, if it occurs, has a positive or negative e ect on one or more
project objectives such as scope, schedule, cost, or quality" [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ], and many risk
management approaches exist, aimed at identi ng, quantifying and mitigating
risk. The notion of `uncertain event' is an indication that uncertainty and risk
are closely related concepts, although there is growing recognition of their
differences. For instance, [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] takes a knowledge-centric view to distinguish between
di erent kinds of uncertainty, summarised in the four quadrant model
reproduced in Figure 1.
      </p>
      <p>
        In Cleden's view [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], all projects start with inherent uncertainty, some of
which is susceptible to risk analysis, which transforms some uncertain events into
risk, but still leaves latent uncertainly, which requires management approaches
distinct from traditional risk management.
      </p>
      <p>One of our objectives is to explicate how traditional and agile project
management deal with risk and uncertainty in complex projects.</p>
    </sec>
    <sec id="sec-3">
      <title>Complex project management as complex problem solving</title>
      <p>
        Ahern et al. [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] argue that complex project management should be seen as a form
of complex problem solving. They highlight two fundamental aspects: learning,
which allows the creation, organisation and coordination of emergent knowledge
that cannot be speci ed at the outset; and fostering a common will of mutual
interest among project stakeholders. The latter is similar to Conklin's
coherence [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] | stakeholders having shared understanding and shared commitment
to project objectives and success. These two aspects relate directly to knowledge
and social complexity.
      </p>
      <p>
        In line with this thinking, in our research, we look at complex project
management through the lens of Problem Oriented Engineering (POE, see [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] for a
comprehensive introduction), a design theoretic framework for complex problem
solving. POE has been applied in real-world case studies as a systematic
approach to address a wide range of engineering and organisational problems (for
instance, [
        <xref ref-type="bibr" rid="ref6 ref9">6, 9</xref>
        ]).
      </p>
      <p>POE is concerned both with di erent types of knowledge, spanning problem
and solution spaces, and with stakeholders with a role in the problem solving
process. In essence, a POE problem is a recognised (real-world) need in
context, whose solution satis es it. Arriving at a solution is a process in which
need, context and solution are progressively `explored' and `validated.' During
exploration, learning takes place so that stakeholders come together to create,
organise and exchange knowledge, which reduces knowledge complexity, while
validation records stakeholders' satisfaction on the outcome of exploration,
reducing uncertainty and contributing to coherence.</p>
      <p>Explorations take time and e ort, so that expenditure and project risk is
accumulated during such activities. Through validation, explorers transfer risk
to validating stakeholders. When validation fails, backtracking to a previous
state, including project start, may be the outcome.</p>
      <p>In its idealised form, such a process is captured by the pattern in Figure 2.
The pattern relates fundamental activities and actors and is not a prescriptive
model | a process may be linear, iterative, spiral, fractal, etc.</p>
      <p>Validation</p>
      <p>Problem exploration
(problem explorers)</p>
      <p>Solution exploration
(solution explorers)</p>
      <p>Validation</p>
      <p>In summary, as caputured by the PPP, complex project management is a
problem solving endeavour to design solutions to organisational problems (need
in context), and in which knowledge and social complexity are tackled through
problem and solution explorations and validations, reducing uncertainty and
mitigating risk.</p>
      <p>Our conjecture is that PPP and its underlying concepts provide a fruitful
theoretical framework in which to analyse risk characteristics of traditional and
agile project management approaches when interpreted as problem solving
processes. In the next section we put this idea to the test by proposing a model for
project risk arising from problem (need in context) volatility.
4</p>
    </sec>
    <sec id="sec-4">
      <title>Problem drift</title>
      <p>Traditional project management approaches expect projects to be completely
planned in advance, with their execution merely a process of implementation.
As a consequence, resources are committed to a chosen solution early in the
project lifecycle. Even if we were to discount knowledge complexity | which
prevents both problem and solution from being completely knowable at the onset
| such a commitment is particularly risky in the presence of problem volatility,
due, for example, to rapid market or technological change (context volatility)
or stakeholder con icts (need volatility). If one were to take the same approach
to archery, one would identify a target and aim, close ones eyes, pull back the
string and let an arrow go. In the case that the target is static, such an approach
might be appropriate. But what in the case of a moving target? The arrow will
land where the original target was, not where it has moved to.</p>
      <p>Thus, in traditional approaches, xing a solution choice early incurs the risk
that the problem will have moved as a product of the volatility of the
organisation's problems (need in context): the more volatile the problem, the higher
the likelihood that a delivered solution will `miss' its target, i.e., the delivered
solution does not satisfy the need in context. Instead, we must track the target
as it `moves': this is where validation has a role to play.</p>
      <p>To understand `problem drift', we propose the `problem drift model'
illustrated in Figure 3:
{ the vertical axis represents `problem drift', which is a measure of divergence
from the problem the project was set up to solve and that which is in the
real world, as a result of problem volatility;
{ the horizontal axis represents resource use (equivalently, the passage of time)
from most recent validation (initially project front-end);
{ we assume an `acceptable drift range' (the shaded area), where the divergence
is not su cient to invalidate development of the solution;
{ the `drift rates' lines indicate the degree of problem volatility: from high (V1),
i.e., the environment changes very quickly, to low (V3), where it changes more
slowly.</p>
      <p>Marked on the horizontal axis is a `validation point,' which is the point where
validation against the problem is sought on some validation artefact from
stakeholders. Three situations are considered: i) in a situation of low drift (V3), drift
has occurred but the validation artefact can still be validated; ii) when medium
drift (V2), drift leads to a marginal call on the boundary between acceptable and
unacceptable drift; iii) when high drift (V1), the validation artefact cannot be
validated and some or all development resource is lost: based on the knowledge
gained, a previous project state may be revisited or, in the extreme, the project
is abandoned.</p>
      <p>itrf
D</p>
      <p>V1:Highdriftrate</p>
      <p>unacceptable drift
V2: medium drift rate
marginal drift</p>
      <p>V3: Low drift rate
acceptable drift
validation point</p>
      <p>
        Under this model, the impact of problem drift relates to lost development
resource, and risk accumulation is then a function of resource expenditure and
drift rate, with validation the means to manage risk. This is consistent with
empirical evidence [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] in software projects which suggests that more frequent
developer/customer communication (a form of validation) lessens the impact of
requirements volatility.
      </p>
      <p>
        Seen this way, we may interpret the role of validation in various project
management approaches. At the extremes:
{ in extreme plan-driven methods, such as Royce's posited Waterfall model
[
        <xref ref-type="bibr" rid="ref14">14</xref>
        ], validation would occur only at project end. Unless the drift rate is
zero or extremely low, any delivered solution to the original problem will be
unacceptable. This corresponds to traditional approaches being appropriate
only in situations of low drift (with the caveat that knowledge complexity
would still pose a challenge);
{ in extreme agile methods, validation occurs early and often so that, even in
situations of medium to high drift, unacceptable drift is never experienced.
The related risk of failure is thus reduced.
      </p>
      <p>One might ask, if agile copes with all drift rates, why not eschew plan-driven
methods altogether? Indeed, this view might be the source of the popular view
that all processes should be agile. Our model also explains why this is not the
case, however: validation requires time and e ort, and so consumes resources,
diverting them from development. As a result, agile processes `pay' for their
management of risk through potentially expensive validation.</p>
      <p>There is therefore a balance to be struck between agile and plan-driven: the
model suggests that the optimal balance is to validate at, or just before, the
point of marginal drift (V2). To do this a number of things are required: i)
the measurement of problem volatility; ii) the notion of acceptable drift; and iii)
ways of combining traditional and agile methods to support the optimal balance.
5</p>
    </sec>
    <sec id="sec-5">
      <title>Discussion and Future Work</title>
      <p>Complex project management is challenging for both traditional and agile
approaches: traditional techniques may be left behind by unrecognised
environmental change in a volatile context, while in a stable environment, agile may
require too expensive interaction with the client. One area of growing interest is
how traditional and agile may combine to increase the chance of project success.
Yet how to strike a balance between the two remains poorly understood.</p>
      <p>
        In this position paper, we have proposed a model for complex socio-technical
projects related to risk arising from problem volatility, that tries to explain
the balance of agile and traditional. The model is located within the Problem
Oriented Engineering (POE) framework of the second and third authors [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]
and, in particular, derives from the POE Process Pattern (PPP). The model
introduces the concept of drift rate as a measure of problem volatility, with the
impact of problem drift related to loss of development resource, risk accumulation
as a function of resource expenditure and drift rate, and validation the means
to manage risk.
      </p>
      <p>
        A di erent characterisation of tradition versus agile is given in [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], which takes
inspiration from the SECI model for knowledge transformation in organisations
[
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] to explicate and compare how tacit, explicit and embedded knowledge are
transferred during traditional vs. agile software development. The main insight is
that traditional methods rely on explicit forms (e.g., requirements speci cations,
design models) to communicate with a variety of specialist stakeholders, while
in agile methods, tacit knowledge is shared through `Socialization' (i.e., direct
communication between problem owners and development team) supported by
`Embedment', in which knowledge is embedded in the software system through
coding. With reference to the PPP, these forms of knowledge transfer fall within
exploration, but the di erent types of transfer are not di erentiated by the
pattern. Instead, PPP is concerned with the accumulation of risk during exploration
and its mitigation via validation. This suggests that the two approaches can be
combined and may thus deliver orthogonal bene ts.
      </p>
      <p>The drift model proposed presupposes that drift can be measured and
predicted. The objective of future research will be to explore if these measurement
and prediction are feasible and how to implement them. For instance, it is
plausible that measuring how problem descriptions change over time is one possible
proxy measure for context volatility. However, more sophisticated notions should
also be considered.</p>
      <p>
        Supposing that our drift model works, the question arises as to the extent we
can optimally combine agile with traditional processes. This would require some
hybrid process architecture to be developed. The second and third authors have
already taken preliminary steps in the analysis of the agile/plan-driven mix in
the context of software projects in [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], but much remains to be done.
      </p>
      <p>
        Finally, in our model we have focused on problem volatility and process
activity, irrespective of organisational culture, which is an acknowledged key success
factor for agility [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Any cultural implication of our model will be considered in
future research.
      </p>
    </sec>
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