Knowledge and Process Management Volume 11 Number 2 pp 137–154 (2004)
Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/kpm.199
& Research Article
Fuzzy Cognitive Maps as a Back
End to Knowledge-based Systems
in Geographically Dispersed
Financial Organizations
George Xirogiannis1*, Michael Glykas1 and Christos Staikouras2
1
2
Department of Financial and Management Engineering, University of the Aegean, Greece
Department of Accounting and Finance, Athens University of Economics and Business, Greece
This paper addresses the problem of designing a knowledge management methodology tool to
act as a decision support mechanism for geographically dispersed financial enterprises. The
underlying research addresses the problem of information capture and representation in financial institutions in order to provide an implementation of the virtuous cycle of knowledge flow.
The proposed methodology tool utilizes the fuzzy causal characteristics of Fuzzy Cognitive
Maps (FCMs) to generate a hierarchical and dynamic network of interconnected financial performance concepts. By using FCMs, the proposed mechanism simulates the operational efficiency of distributed organizational models with imprecise relationships and quantifies the
impact of the geographically dispersed activities to the overall business model. Generic adaptive maps that supplement the decision-making process present a roadmap for integrating hierarchical FCMs into the business model of typical financial sector enterprises. Copyright # 2004
John Wiley & Sons, Ltd.
INTRODUCTION
Knowledge has been defined by Western philosophy (Russell, 1989) as ‘justified true belief’. However, as long as there is a chance that this belief is
mistaken and as long as there is an evolution of
technologies, theories, practice and behaviours,
this definition invites individuals and groups to
develop constantly ‘what they think that they
know’ (Nonaka and Takeushi, 1994). This continuous process of creation of new insights and beliefs
is what fuels the entire paradigm of knowledge
management and even constitutes the fundamental
rationale for the existence of an enterprise. Some
*Correspondence to: George Xirogiannis, Department of Financial and Management Engineering, University of the Aegean,
31 Fostini Street, Chios, 82 100, Greece.
E-mail: g.xirogiannis@fme.aegean.gr
Copyright # 2004 John Wiley & Sons, Ltd.
argue that instead of merely solving problems,
organizations create and define problems, develop
and apply new knowledge to solve problems and
then develop further new knowledge through the
action of problem solving. In this view an enterprise creates continuously new knowledge through
action and interaction, not acting simply as an
information-processing machine (Nonaka and
Takeushi, 1994; Spencer and Grant, 1996).
Currently, there is a pressing need for sharing
knowledge among the financial managers (e.g.
CFO, Head of Accounting, Head of Budgeting,
Head of Business Planning). The effect of knowledge attrition for customers and investors is knowledge intensive. Financial enterprises lose (on
average) half of their knowledge base every 5–10
years due to the turnover of their employees. The
fact is that financial managers are usually more
committed to their specialized profession, thus
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losing sight of the enterprise as a whole. Without
effective sharing and maintenance of knowledge,
financial institutions risk losing their crucial knowledge through labour mobility. Moreover, knowledge has the idiosyncrasy that its value can only
be realized when it is put in use (i.e. no shelf value).
The more knowledge put in use, the more its value
is appreciated (e.g. efficient use through the
increase in confidence of application and learning),
rather than depreciated, as other physical assets of
machinery or natural resources.
This paper addresses the problem of designing a
novel knowledge management (KM) methodology
tool to act as a decision support mechanism for
geographically dispersed financial organizations
(e.g. multi-national enterprises, multi-branch
banks). The proposed methodology tool utilizes
the fuzzy causal characteristics of fuzzy cognitive
maps (FCMs) to generate a hierarchical and
dynamic network of interconnected financial performance concepts. By using FCMs, the proposed
mechanism simulates the operational efficiency of
distributed organizational models with imprecise
relationships and quantifies the impact of the geographically dispersed activities to the overall business model.
From the KM perspective, it is the belief of this
paper that optimal decision-making can be
achieved through the creation of a virtuous circle
of knowledge flow: creating and adding knowledge, successful searching for the required pieces
of knowledge, feedback for impetus to assert quality knowledge again.
Primarily, the proposed model targets the principal beneficiaries and stakeholders of KM projects
(financial administration, change management leaders, etc.), assisting them to reason effectively
about the status of financial performance metrics,
given the (actual or hypothetical) implementation
of a set of business model changes. Nevertheless,
the explanatory nature of the mechanism can prove
to be useful in a wider educational setting.
This paper consists of seven sections. The next
section presents a short literature overview, while
the third section addresses the contemporary knowledge capture and representation problem of financial managers and justifies the need for a novel
adaptive knowledge management methodology
tool. The fourth section presents an overview of
the proposed system, the fifth section discusses
the new approach to knowledge modelling based
on FCMs and the sixth section discusses the major
advantages of the proposed tool. The final section
concludes this paper and briefly discusses future
research activities.
LITERATURE OVERVIEW
FCMs as a modelling technique
FCMs are a modelling methodology for complex
decision systems, which originated from the combination of fuzzy logic (Zadeh, 1965) and neural networks. An FCM describes the behaviour of a
system in terms of concepts; each concept represents an entity, a state, a variable or a characteristic
of the system (Dickerson and Kosko, 1997).
FCM nodes are named by such concepts forming
the set of concepts C ¼ {C1, C2, . . . , Cn}. Arcs (Cj, Ci)
are oriented and represent causal links between
concepts; that is how concept Cj causes concept Ci.
Arcs are elements of the set A ¼ {(Cj, Ci)ji} C C.
Weights of arcs are associated with a weight value
matrix Wn n, where each element of the matrix
= A then
wji 2 [1, . . . , 1] R such that if (Cj, Ci) 2
wji ¼ 0 else excitation (respectively inhibition)
causal link from concept Cj to concept Ci gives
wji > 0 (respectively wji < 0). The proposed methodology framework assumes that [1, . . . , 1] is a
fuzzy bipolar interval, bipolarity being used as a
means of representing a positive or negative
relationship between two concepts.
In practice, the graphical illustration of an FCM
is a signed graph with feedback, consisting of
Weight
nodes and weighted interconnections (e.g.
!).
Signed and weighted arcs (elements of the set A)
connect various nodes (elements of the set C) representing the causal relationships that exist among
concepts. This graphical representation (e.g.
Figure 1) illustrates different aspects in the behaviour of the system, showing its dynamics (Kosko,
1986) and allowing systematic causal propagation
(e.g. forward and backward chaining).
Figure 1 Basic constructs of FCMs
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Figure 2 Simple FCM
Positive or negative sign and fuzzy weights
model the expert knowledge of the causal relationships (Kosko, 1991). Concept Cj causally increases
Ci if the weight value wji > 0 and causally decreases
Ci if wji < 0. When wji ¼ 0, concept Cj has no causal
effect on Ci. The sign of wji indicates whether
the relationship between concepts is positive
ji
ji
Ci) or negative (Cj w!
Ci), while the value
(Cj w!
of wji indicates how strongly concept Cj influences
concept Ci. The forward or backward direction of
causality indicates whether concept Cj causes concept Ci or vice versa (e.g. Figure 2).
Simple variations of FCMs mostly used in business decision-making applications may take trivalent weight values [1, 0, 1]. This paper allows
FMCs to utilize fuzzy word weights like strong,
medium or weak, each of these words being a fuzzy set to provide complicated FCMs. In contrast,
Kwahk and Kim (1999) adopted only a simple
relative weight representation in the interval
[1, . . . , 1]. To this extent, Kwahk and Kim (1999)
offered reduced functionality since it does not
allow fuzzy weight definitions.
Generally speaking, FCM concept activations take
their value in an activation value set V ¼ {0, 1} or
{1, 0, 1} if in crisp mode or [, 1] with ¼ 0 or 1 if
in fuzzy mode. The proposed methodology
framework assumes fuzzy mode with ¼ 1. At step
t 2 N, each concept Cj is associated with an inner activation value ajt 2 V, and an external activation value
etaj 2 R. FCM is a dynamic system. Initialization is
aj0 ¼ 0. The dynamic obeys a general recurrent relation atþ1 ¼ f (g(eat, WT at)), 8t 0, involving weight
matrix product with inner activation, fuzzy logical
operators (g) between this result and external forced
activation and finally normalization ( f ). However,
this paper assumes no external activation (hence no
fuzzy logical operators), resulting in the following
typical formula for calculating the values of concepts
of FCM:
0
1
n
X
atþ1
wji atj A
ð1Þ
¼ f@
i
j¼1; j6¼i
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where aitþ1 is the value of concept Ci at step t þ 1,
aja the value of the interconnected concept Cj at
step t, wji is the weighted arc from Cj to Ci and
f : R ! V is a threshold function, which normalizes
activations. Two normalization functions are usually used. The unipolar sigmoid function where
> 0 determines the steepness of the continuous
function fðxÞ ¼ 1þe1x . When concepts can be negative ( < 0), function fðxÞ ¼ tanhðxÞ can also be
used.
To understand better the analogy between the
sign of the weight and the positive/negative relationship, it may be necessary to revisit the characteristics of the fuzzy relation (Kaufmann, 1975; Lee
et al., 2002). A fuzzy relation from a set A to a set B
or (A, B) represents its degree of membership in
the unit interval [0, 1]. Generally speaking, sets A
and B can be fuzzy sets. The corresponding fuzzy
membership function is mf:A B ! [0, 1]. Therefore, mf(x, y) is interpreted as the ‘strength’ of the
fuzzy membership of the fuzzy relation (x, y)
where x 2 A and y 2 B. Then this fuzzy relation concept can be denoted equivalently as x f
! y and
applied to interpret the causality value of FCM,
since wji (the causality value of the arc from nodes
Cj to Ci) in a certain FCM is interpreted as the
degree of fuzzy relationship between two
nodes Cj and Ci. Hence, wji in FCMs is the fuzzy
membership value mf(Cj, Ci) and can be denoted
ji
Ci.
as Cj w!
However, we understand that the fuzzy relation
(weight) between concept nodes is more general
than the original fuzzy relation concept. This is
because it can include negative () fuzzy relations.
Fuzzy relations mean fuzzy causality; causality can
have a negative sign. In FCMs, the negative fuzzy
relation (or causality) between two concept nodes
is the degree of a relation with a ‘negation’ of a
concept node. For example, if the negation of a
concept node Ci is noted as Ci, then mf(Cj, Ci) ¼
0.6 means that mf(Cj, Ci) ¼ 0.6. Conversely,
mf(Cj, Ci) ¼ 0.6 means that mf(Cj, Ci) ¼ 0.6.
FCMs help to predict the evolution of the system
(simulation of behaviour) and can be equipped
with capacities of Hebbian learning (Kosko,
1986a, 1998). FCMs are used to represent and to
model the knowledge on the examining system.
Existing knowledge of the behaviour of the system
is stored in the structure of nodes and interconnections of the map. The fundamental difference
between FCMs and neural networks is in the fact
that all the nodes of the FCM graph have a strong
semantic defined by the modelling of the concept,
whereas the nor input/nor output nodes of the
graph of the neural network have a weak semantic,
only defined by mathematical relations.
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Applications of fuzzy cognitive maps
Over the last 10 years, a variety of FCMs have been
used for capturing—representing knowledge and
intelligent information in engineering applications,
for instance, geographical information systems Liu
and Satur (1999) and fault detection (Ndouse and
Okuda, 1996; Pelaez and Bowles, 1995). FCMs
have been used in modelling the supervision of distributed systems (Stylios et al., 1997). FCMs have
also been used in operations research (Craiger
et al., 1996), web data mining (Hong and
Han, 2002; Lee et al., 2000), as a back end to
computer-based models and medical diagnosis
(e.g. Georgopoulos et al., 2002).
Several research reports applying basic concepts
of FCMs have also been presented in the field of
business and other social sciences. Research in
Axelrod (1976) and Perusich (1996) have used
FCM for representing tacit knowledge in political
and social analysis. FCMs have been successfully
applied to various fields such as decision making
in complex war games (Klein and Cooper, 1982),
strategic planning (Diffenbach, 1982; Ramaprasad
and Poon, 1985), information retrieval (Johnson
and Briggs, 1994) and distributed decision process
modelling (Zhang et al., 1994). Research like that of
Lee and Kim (1997) has successfully applied FCMs
to infer rich implications from stock market analysis results. Research like that of Lee and Kim (1998)
also suggested a new concept of fuzzy causal relations found in FCMs and applied it to analyse and
predict stock market trends. The inference power of
FCMs has also been adopted to analyse the competition between two companies, which are assumed
to use differential games mechanisms to set up
their own strategic planning (Lee and Kwon,
1998). FCMs have been integrated with case-based
reasoning technique to build organizational memory in the field of knowledge management (Noh
et al., 2000). Recent research adopted FCMs to support the core activities of highly technical functions
like urban design (Xirogiannis, 2004). Summarizing, FCMs can contribute to the construction of
more intelligent systems, since the more intelligent
a system becomes, the more symbolic and fuzzy
representations it utilizes.
In addition, a few modifications have been proposed. For example, the research in Silva (1995)
proposed new forms of combined matrices for
FCMs, the research in Hagiwara (1992) extended
FCMs by permitting non-linear and time delay on
the arcs, and the research in Schneider et al.
(1995) presented a method for automatically constructing FCMs. More recently, Liu and Satur
(1999) have carried extensive research on FCMs,
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investigating inference properties of FCMs, proposed contextual FCMs based on the objectoriented paradigm of decision support and applied
contextual FCMs to geographical information systems (Liu, 2000).
KNOWLEDGE MANAGEMENT IN
FINANCIAL ENTERPRISES
The decision-making problem
Financial management is one of the major areas of
business of financial sector institutions. The risks
undertaken by fund managers in their investment
decisions affect directly the institutions’ business
continuity, profitability and reputation. Fund managers’ work allows direct performance measurement, while the rewards based on measured
performance affect their career prospects and job
security. Junior financial managers are therefore
more risk averse in their portfolio management
decisions, which they ‘herd’ to follow the market
trends in avoiding investment risks above the market objective level, whereas senior managers are
given more discretion in their investment decisions. The high monetary rewards, considerations
of job security and market-relative measurement
of performance induce financial managers’ selfinterests and ownership of critical knowledge,
which may create effective investment decisions.
Therefore creating an open environment to share
analytical skills of market signals, intimate knowledge of clients, or capability to sense political atmosphere and market sentiment among financial
managers can minimize any miscalculated risks.
The need for knowledge sharing
Knowledge can be reused potentially an infinite
number of times without wearing off or needing
repair. With each subsequent application of information processing, the experience of use and background understanding of environmental settings
builds up. This potential to apply knowledge an
infinite number of times allows for economies of
scale, which may reduce radically the transaction
and/or operational costs. Hence the potential value
of knowledge can only be fully realized if it is leveraged effectively through sharing and reuse.
Intimate, contextual and firm-specific knowledge
is an intangible asset that is costly to develop,
hard to replace and time consuming to replicate.
Possession of intimate knowledge with real value
to customers allows enterprises to differentiate
themselves
from
competitors.
Coordinated
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processing of disparate pieces of information to
develop skills and capabilities in a way that helps
an enterprise to achieve its goals is a form of intellectual capital and a valuable source of competitive
advantage. Individuals with different culture and
experiences lack the contextual links associated
with the enterprise’s specific knowledge. Communication of knowledge separated from its context
hinders thorough understanding and detaches
intuitive interpretation through symbolic environmental associations. Knowledge so communicated
is inevitably abstract. It consists of generalized analyses of events, and the recipient may find it difficult to comprehend its relevance to a specific
situation. Indeed, skilful masters differentiate
from novices by the intimate understanding of
the tasks and the environment linked together
with specific contextual interacting factors that differentiate skillful masters from novice beginners.
Sharing, and only communication, of knowledge
carries a common context where individuals can
interact and engage in a mutual dialogue with common understanding. Effective sharing creates a
synergy with value where the sum is more than
its parts. Therefore, effective dissemination of specialized contextual knowledge among members of
the firm minimizes miscalculation or misperception of risks.
KM and transaction costs reduction
Sharing of knowledge involves information flows
between the distributed organizational entities of
an enterprise. The cost—benefit analysis of knowledge flow must consider the enterprise’s specific
environmental factors in terms of co-location of
decision rights and knowledge. Colocation refers
to the delegation of decision-making authority to
the party holding necessary knowledge (e.g. discretionary investment decisions made by financial
managers within institutional guidelines).
The cost of no knowledge sharing can be proportional to the decision-making costs (in practice, the
sum of agency and knowledge transfer costs).
Agency cost arises from self-interested individuals
in conflict with management when decisions are
delegated to them. The time and effort spent by
management and possibly the need for policy
adjustments, remuneration packages and coordination of individual members are all agency costs.
The knowledge transfer costs arise from training,
practice and experience needed to equip individuals with the necessary knowledge.
The distance of decision rights from the CEO
office affects the total decision-making costs and
causes trade-offs between suboptimal decisions
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and possession of necessary knowledge. The lack
of embedded know-how at central management
causes suboptimal decisions to be made when the
decision-maker is away from sources of knowledge; therefore the knowledge transfer costs owing
to poor information sharing is very high. On the
other hand, when some knowledge carrier away
from central management makes a decision, the
need for control and coordination to maintain consistency and integrity incurs high agency costs.
There is a cost-optimal point where the sum of
the agency and transfer costs is at its minimum.
Effective knowledge sharing lowers the costs by
shifting the optimal point of total organizational
costs downward, i.e. shifting the knowledge transfer cost curve downward. This component identifies the agency and knowledge transfer costs
involved in sharing knowledge in the current
environment setting to ensure organizational fit.
FUNDAMENTALS OF THE
METHODOLOGY TOOL
The knowledge flow cycle
Many financial analysts and investigation reports
about multi-million dollar losses at Sumitomo and
Barings attribute the losses to the neglect of paying
attention to operational risk. Operational risk
results in losses due to deficiencies in information,
personnel unavailability, human error, and inadequate procedures and control. Also, financial managers who have practical knowledge about trading
risks become reluctant to share their knowledge
with other organizational entities. By nature, most
of these risks are difficult to quantify and therefore
are handled arbitrarily. Thus, many analysts
recommend that financial enterprises utilize comprehensive systems for capturing and monitoring
risk, accompanied by an automated risk-reporting
process. These reports should be easily read and
understood by top management.
Such problems require technology and management tools to motivate financial managers’ willingness to offer information, identify the need for
information processing, support top management
to deal with multi-attribute problems and achieve
balanced and well-informed decisions. It is the
view of this paper that optimal decision-making
can be achieved through the creation of a virtuous
cycle of knowledge flow (Figure 3). This paper
adopts this knowledge flow sequence to propose,
under the non co-location situation, an adaptive
enabling mechanism that will allow a financial
enterprise to integrate knowledge capture as a
back end to its intelligent decision-making process.
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Figure 3 Virtuous circle for knowledge flow
Knowledge flow implementation
The proposed tool addresses the following KM problems of financial institutions in order to provide an
implementation of the virtuous cycle of knowledge
flow as presented in Figure 3: the tool aims to
become a means for knowledge sharing and capture,
as well as distributed KM in financial enterprises.
The current implementation of the proposed methodology tool consists of the following modules:
Knowledge capture. This module allows the user
to generate graphically adaptive and highly flexible entity relationship diagrams (e.g. influence
diagrams, cause- and -effect diagrams) from the
information items provided by internal databases as well as external relevant sources. Information items then are linked in FCMs for the
assertion of knowledge in a distributed (but
cooperative) manner.
FCM hierachy. Knowledge capture allows distributed FCMs to be associated and concepts to be
composed/decomposed via node linking. In
practice, node linking generates multi-branch
FCM hierarchies (as defined in Xirogiannis et al.,
2004). FCM hierarchies are twofold:
—distributed decomposition of FCMs to encode
and analyse specific contexts in their individualistic behaviour;
—adaptive synchronization of FCMs on a project level (e.g. major organizational units,
functional areas) in the hierarchy.
Knowledge alerts. This module associates specific
alerts to the predefined threshold values of
knowledge entities and distributes corresponding messages to individual managers. Alerts
and real-time data is to be provided via the existing intranet/Internet message-passing technology of the enterprise.
Work flow simulator. This module implements
the FCM inference engine based on the FCM
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value generator algorithms (see next section).
The FCM inference engine may interact dynamically with methodology tools, which plan and
monitor business performance (such as the
Adjust engine also implemented by the research
team) to define and measure specialized performance indicators. Moreover, the inference engine
can be extended (on demand) with intelligent
functions like abductive reasoning (Flach and
Kakas, 1998) to integrate intelligent reverse engineering functionality.
Database link module. Future implementation of
the system will also provide the user with the
capability to interface existing databases of the
enterprise directly with the Know Fuz system.
These core modules (Figure 4) form the current
implementation (also know as ‘Know Fuz’ implementation) of the proposed system, which may
associate both quantitatively and qualitatively disperse financial information stored in the internal
and external databases to extract meaningful
knowledge as a back end to intelligent decision
making.
FCMs in financial modelling
The proposed system extends this typical FCM
algorithm (also used in Kwahk and Kim, 1999) by
proposing the following new algorithm aiming at
modelling more effectively the geographically dispersed nature of the financial enterprise domain:
Atþ1
i
n
X
t
t
Wj1 Aj
¼ f k1 A i þ k2
ð2Þ
j¼1; j6¼1
The coefficient k1 represents the proportion of the
contribution of the value of the concept Ai at time t
in the computation of the value of Ai at time t þ 1.
In practice, this is equivalent to assuming that
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Figure 4 Know Fuz functional overview
Wii ¼ k1. The incorporation of this coefficient results
in smoother variation of concept values during the
iterations of the FCM algorithm. The coefficient
k2 expresses the ‘influence’ of the interconnected
concepts in the configuration of the value of the
concept Ai at time t þ 1. In practice, it indicates
the centralized or decentralized importance (e.g.
decentralization distance) of the concept Ai in
comparison to other concepts of the map. Also, it
may indicate the sufficiency of the set of concepts
Aj j 6¼ i, in the estimation of the value of the concept Ai. This paper also assumes that k1 and k2
can be fuzzy sets, extending previous relevant
research.
To demonstrate financial modelling using FCMs,
consider Figure 5, which depicts a graphical example of fuzzy relationships with no feedback loops,
followed by sample numerical calculations using
formula (2), with k1 ¼ k2 ¼ 1 and ¼ 5 as the steepness of the normalization function.
Figure 5 Sample FCM calculations with no feedback loop
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Figure 6 Sample FCM calculations with feedback loop
Setting the input value of ‘sales volume’ to 0.5
(1st scenario) triggers the FCM formula. The formula then calculates the current values of all
related concepts. A ‘zero’ concept value indicates
that the concept remains neutral, waiting for causal
relationships to modify its current value. A generic
interpretation of the first scenario indicates that if
sales volume increases by 50% then the income
may increase by 88.07% and the profitability by
95.61%. In contrast, if the sales volume increases
by 20% (2nd scenario), then the income and profitability may increase by 59.86% and 89.04%
respectively.
Figure 6 presents a typical example of a feedback
loop. Similarly to Figure 5, changing the input
value of ‘sales volume’ triggers the FCM formula.
However, the feedback loop dictates that calculations stop only when an equilibrium state for all
affected concepts has been reached, modifying all
input values accordingly.
istics, local economy principles such as interest
rates, etc.).
Integrated category: essentially all top-most concepts (e.g. a concept Ai with no backward causality such that 8j : wji ¼ 0), or concepts which may
fall under more than one main categories.
This categorization is compatible both with
either the ‘process view’ or the ‘organizational
view’ (as adopted by Kwahk and Kim, 1999) of
the enterprise to allow greater flexibility in modelling dispersed knowledge flows. The hierarchical
decomposition of knowledge concepts generates a
set of dynamically interconnected hierarchical
FCMS IN KNOWLEDGE MODELLING
FCM categories
The current implementation of the proposed system encodes generic maps that can supplement
the knowledge modelling of typical geographically
dispersed financial organizations. The proposed
FCMs may store concepts under different map
categories (Figure 7); for example:
Business category: all concepts relating to core
financial activities.
Technical category: all infrastructure-related concepts, with emphasis on technology infrastructure.
Social category: all HR-related concepts, accompanied by external stimuli (e.g. market character-
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Figure 7 Map categories
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Figure 8 Alignment of the organizational hierarchy with the FCM knowledge hierarchy
maps. Each map analyses further the relationships
among concepts at the same hierarchical level. Consider, for example, a generic organizational chart of
a typical bank (Figure 8). A simple rule of thumb
for generating hierarchies is by aligning FCMs
with the organizational levels of the enterprise.
Figure 9 presents such a sample map hierarchy,
which also serves as the FCMs overview.
Currently, the mechanism integrates more than
250 concepts, forming a hierarchy of more than
15 maps. Its dynamic interface allows its users to
utilize a subset of these 250 concepts by setting
the value of the redundant concepts and/or the
value of the associated weights to zero.
The proposed system can portray the financial
model following either a holistic or a scalable
Figure 9 Sample FCM hierarchy
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approach. This is analogous to seeing the enterprise either as a single, ‘big bang’ event or as an
ongoing activity of targeting successive tasks of
selected sub-processes. The proposed mechanism
can accommodate both approaches. Essentially,
the implementation can decompose concepts to
their constituent parts (sub-concepts) on demand
and let the user reason about lower-level hierarchies of FCM before it passes values to the higherlevel hierarchies. The proposed mechanism also
allows the user to specify the degree of FCM
decomposition during the map traversal. Instead
of waiting for a lower-level FCM to traverse its
nodes and pass its value to higher-level map hierarchies, the user may assign directly an external
value to nodes which link hierarchies. In practice,
the simulation is carried out as if there are no links
with other FCMs. Also the current implementation
allows:
easy customization of the function f and easy
reconfiguration of the formula Ati þ 1 to adapt
to the specific characteristics of individual
enterprises;
generation of scenarios for the same skeleton
FCM;
automatic loop simulation until a user-defined
equilibrium point has been reached. Alternatively, step-by-step simulation (with graphical
output of partial results) is also available to provide a justification for the partial results.
The following sections exhibit sample skeleton
maps for the business and integrated categories,
which provide relevance and research interest to
this paper.
Business metrics
The mechanism proposes six different maps, each
consisting of generic financial knowledge concepts
as follows:
The ‘differentiation strategy’ map (Figure 10)
reasons on the impact of strategic change to the
competitive identity and financial status of the
enterprise.
The ‘internal cost’ map summarizes concepts,
which affect the overall cost of delivering products (or services) to the clients of the enterprise
(e.g. value chain optimization, staff performance,
execution cost).
The ‘execution cost’ map (Figure 11) exemplifies
concepts that influence the production cost of the
enterprise.
The ‘structural cost’ map reasons on the impact
of concepts like outsourcing, product orientation,
economies of scale, etc., to the overall business
model.
Figure 10 Differentiation strategy FCM
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Figure 11 Execution cost FCM accompanied by a sample input/output/alert interface
The ‘customers’ appreciation’ map reasons on
the impact of customer satisfaction in the differentiation effort and consequent financial results
of the enterprise.
The ‘profit overview’ map (Figure 12) summarizes the effect of concepts like income and
delivery cost on the overall profitability of the
financial enterprise.
Concepts denoted by ‘ # ’ expand further to
lower-level maps. Similarly, ‘ " ’ denotes bottomup causal propagation.
Integrated metrics
The proposed integrated category consists of four
(4) different maps as follows:
Figure 12 Profit overview FCM
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Figure 13 High-level FCM
The ‘high-level’ map (Figure 13) essentially
relates concepts which fall under more than
one category, as well as top-most concepts.
The ‘new entrants’ map supports reasoning of
the impact of business model adjustments to
meet the product standards (e.g. quality, differentiated products, price policies) set by new
competitors.
The ‘productivity’ map (Figure 14) reasons
on the impact of internal efficiency and sales
adequacy on the overall profitability of the
enterprise.
The ‘RAROC’ map (Figure 15) summarizes the
impact of internal efficiency and sales adequacy
on the risk-adjusted return on capital indicator of
the enterprise.
All the above-mentioned maps form a generic
domain of FCMs. This knowledge domain serves
as the basis of the proposed approach and can be
modified to comply with the requirements of specific knowledge-capturing exercises. For example,
further maps in the technical category could relate
concepts that relate the adequacy of the production
cycle with the expected financial performance of
the enterprise (Irani et al., 2002; Valiris and Glykas,
2000).
148
Infrastructure & HR metrics
The mechanism may also integrate various maps
consisting of generic HR category concepts such
as staff performance, motivation, carrier prospects,
financial rewards and workload, as well as ‘social’
metrics which support reasoning of the impact of
knowledge management, training and employee
satisfaction to the financial model. Similarly the
mechanism may also integrate various maps consisting of technical concepts such as centralization/
decentralization of IT infrastructure and IS/IT
effectiveness. While the presentation of such concepts supports the completeness of the proposed
methodology tool, they add little (if any) significance to the research activities presented by this
paper.
Assigning linguistic variables to FCM weights
and concepts
In order to define weight value of the association
rules in an adaptive and dynamic manner, the following methodology is proposed. Financial managers are asked to describe the interconnection
influence of concepts using linguistic notions. Influence of one concept over another is interpreted as a
G. Xirogiannis et al.
Knowledge and Process Management
Figure 14
RESEARCH ARTICLE
Productivity overview FCM
Figure 15 RAROC overview FCM
Fuzzy Cognitive Maps
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RESEARCH ARTICLE
Knowledge and Process Management
linguistic variable in the interval [ 1, 1]. Its term
set T(influence) is:
T(influence) ¼ {negatively
very-very
high, negatively very high, negatively
high, negatively medium, negatively
low, negatively very low, negatively
very-very low, zero, positively veryvery low, positively very low, positively low, positively medium, positively high, positively very high,
positively very-very high}.
This paper proposes a semantic rule M to be
defined at this point. The above-mentioned terms
are characterized by the fuzzy sets whose membership functions are shown in Figure 16.
M(negatively very-very high) ¼ the fuzzy set for
‘an influence close to 90%’ with membership
function nvvh.
M(negatively very high) ¼ the fuzzy set for ‘an
influence close to 80%’ with membership function nvh.
M(negatively high) ¼ the fuzzy set for ‘an influence
close to 65%’ with membership function nh.
M(negatively medium) ¼ the fuzzy set for ‘an
influence close to 50%’ with membership function nm.
M(negatively low) ¼ the fuzzy set for ‘an influence close to 35%’ with membership function nl.
M(negatively very low) ¼ the fuzzy set for ‘an
influence close to 20%’ with membership function nvl.
M(negatively very-very low) ¼ the fuzzy set for
‘an influence close to 10%’ with membership
function nvvl.
M(zero) ¼ the fuzzy set for ‘an influence close to
0’ with membership function z.
M(positively very-very low) ¼ the fuzzy set for
‘an influence close to 10%’ with membership
function pvvl.
M(positively very low) ¼ the fuzzy set for ‘an
influence close to 20%’ with membership function pvl.
M(positively low) ¼ the fuzzy set for ‘an influence close to 35%’ with membership function pl.
M(positively medium) ¼ the fuzzy set for ‘an
influence close to 50%’ with membership function pm.
M(positively high) ¼ the fuzzy set for ‘an influence close to 65%’ with membership function
ph.
M(positively very high) ¼ the fuzzy set for ‘an
influence close to 80%’ with membership function pvh.
M(positively very-very high) ¼ the fuzzy set for
‘an influence close to 90%’ with membership
function pvvh.
The membership functions are not of the same
size since it is desirable to have a finer distinction
between grades at the lower and higher ends of
the influence scale. As an example, three financial
managers proposed different linguistic weights
for the interconnection Wij from concept Ci to concept Cj: (a) positively high, (b) positively very high,
(c) positively very-very high. The three suggested
linguistics are integrated using a sum combination
method and then the defuzzification method of
centre of gravity (CoG) is used to produce a weight
wij ¼ 0.77 in the interval [ 1, 1]. This approach has
the advantage that experts do not have to assign
numerical causality weights but to describe the
degree of causality among concepts. The same
semantic rule and term set can be used to define
the coefficients k1 and k2.
A similar methodology can be used to assign
values to concepts. The financial managers are
also asked to describe the measurement of each concept using, once again, linguistic notions. Measurement of a concept is also interpreted as a linguistic
Figure 16 Membership functions of linguistic variable influence
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G. Xirogiannis et al.
Knowledge and Process Management
variable with values in the interval [ 1, 1]. Its term
set T(Measurement) ¼ T(Influence). A new semantic rule M2 (analogous to M) is also defined and
these terms are characterized by the fuzzy sets
whose membership functions 2 are analogous to
membership functions .
PRELIMINARY EXPERIMENTS
The nature of the experiments
Two informal experiments were conducted by
utilizing metrics from actual (though random)
knowledge-based decision support exercises in
two major financial sector enterprises. For each
experiment, a team of experts was engaged to:
provide linguistic variables for the causal
weights, the concept values and the coefficients
values to let the FCM algorithm reason about
the impact of potential financial performance
changes;
provide their independent expert estimates
(using similar linguistic variables) of the impact
of geographically dispersed activities to the overall business model.
In both cases, the proposed tool iterated a subset
of approximately 150 concepts spread over 10 sample hierarchical maps in order to calculate their
equilibrium values. Both cases run on a typical
business PC with a 2.4 GHz Pentium processor
and 512 MB RAM. As far as the number of iterations is concerned, lower-level maps iterated
10 times on average. The average number of iterations increased to 25 for middle and upper-level
maps. Only the topmost map increased the average
number of iterations to approximately 80 (depending on the initial concept and weight values) due to
the volume of map links. In practice, the actual process time was negligible on such a typical PC.
Discussion
Theoretical value
Various aspects of the proposed modelling
mechanism are now commented on. As far as the
theoretical value is concerned, the proposed
mechanism extends previous research attempts by:
allowing fuzzy node and weight definitions in
the cognitive maps;
introducing a specific interpretation mechanism
of linguistic variables to fuzzy sets;
proposing an updated FCM algorithm to suit better the KM domain of geographically dispersed
organizations;
Fuzzy Cognitive Maps
RESEARCH ARTICLE
supporting node linking to establish map hierarchies and dynamic map selection during
simulation;
concentrating on the actual KM activity and the
associated business model;
allowing dynamic map decomposition and
reconfiguration;
integrating three modes of FCM simulation,
namely bivalent (with a crisp activation set
{0, 1}), trivalent (with a crisp activation set
{ 1, 0, 1}) and linear (with an activation set in
the fuzzy interval [1, . . . , 1]);
supporting the user with appropriate interface
windows when loops, cycles and node conflicts
are identified.
Practical value
As far as the practical value of the proposed
mechanism is concerned:
When compared to the expert estimates, the
mechanism does not provide a fundamentally
different ‘diagnosis’. On the contrary, it provides
reasonably good approximations of the expert
estimates.
The justification of the ‘diagnosis’ (essentially the
metrics decomposition) proved extremely helpful in comprehending the sequence of complex
concept interactions (essentially the knowledge
roadmap).
The concept-based approach did not restrict the
interpretation of the financial impact of geographically dispersed activities to the overall business model. The fuzzy interpretation of concept
and weight values served as indications rather
than precise arithmetic calculations.
The hierarchical (or partial) traversal of financial
metrics improved the distributed knowledge
monitoring throughout the geographical levels
of the enterprise and stipulated targeted communication of the associated financial performance.
The realism of impact estimation depended on
the number of concepts and weights, as well as
on the estimation of their fuzzy characteristics
(weights values, input values, coefficients, etc).
However, the complexity and the length of the
knowledge domain did not discourage the maintenance of the mechanism. Irrelevant and/or
unnecessary knowledge maps could be isolated
on demand to reduce the reasoning effort.
The adaptive nature of the proposed mechanism
is also worth mentioning. For instance:
—the tool can portray either a holistic or a scalable approach to financial modelling to comply with the knowledge modelling approach
of the enterprise;
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RESEARCH ARTICLE
—knowledge categorization is compatible with
either the ‘process view’ or the ‘organizational
view’ of the enterprise;
—hierarchical (and/or decentralized) composition/decomposition of knowledge concepts
couples effectively with the hierarchical
(and/or decentralized) structures of an
enterprise;
—skeleton FCMs accompanied by business cases
(scenarios) improve the flexibility of the tool
by allowing the user to generate alternative
knowledge-based decision roadmaps with little extra effort;
—maps can expand/retract on demand, allowing the user to utilize only the necessary subset
of knowledge concepts;
—maps are dynamic; further knowledge concepts may be added to encapsulate further
knowledge interactions;
—the FCM value calculation formula may
change on demand to adapt better to the
characteristics of the knowledge interactions
of the enterprise.
Added value
Having established the theoretical and practical
value of the proposed mechanism, it is useful to
discuss also the added value of incorporating
such a mechanism into KM exercises. It is the belief
of this paper that the resulting tool provides real
value to the principle beneficiaries and stakeholders of KM projects. For example:
The mechanism eases significantly the complexity of deriving knowledge-based decisions. Informal experiments indicated that the time required
by experts to estimate manually the extensive
impact of major changes to geographically dispersed business models could pose a considerable overhead. On the other hand, the elapsed
time for automated knowledge-based decision
support using FCM can be insignificant, once
the map hierarchies have been set up.
To extend further this syllogism, realistic
knowledge-based decision support should involve continuous argument of change options
(e.g. application of best practices, alternative strategic scenarios) until an equilibrium solution
accepted by all stakeholders has been agreed
upon. Informal discussions with the principal
beneficiaries and stakeholders of the two financial sector enterprises revealed that the proposed
knowledge-based support can reduce significantly the impact estimation overheads, letting
the stakeholders focus on the actual financial
management exercise while exploring in depth
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Knowledge and Process Management
all alternatives and effectively controlling major
change initiatives.
The proposed mechanism can also assist the
financial performance evaluation of the enterprise on a regular basis. FCMs may serve as a
back end to performance score cards (Bourne
et al., 2000; Kaplan and Norton, 1996, 2001) to
provide holistic strategic performance evaluation
and management. However, a detailed analysis
of this extension is beyond the scope of this
paper.
Preliminary usability evaluation
Senior managers of the two major financial sector
enterprises have evaluated the usability of the proposed tool and have identified a number of benefits
that can be achieved by its utilization. Detailed presentation of the usability evaluation results are
beyond the scope of the paper. However, a summary of major business benefits (as identified by
senior managers) is provided to improve the autonomy of this paper:
Shared goals:
—Concept-driven KM pulls individuals together
by providing a shared direction and determination of internal change.
—Shared KM and financial performance measurement enable business units to realize
how they fit into the overall business model
and what is their actual contribution.
—Senior management receives valuable input
from the business units (or the individual
employees) who really comprehend the weaknesses of the current business model as well as
the opportunities for performance-driven
changes.
Shared culture:
—All business units feel that their individual
contribution is taken into consideration
and provide valuable input to potential business model changes.
—All business units and individuals feel confident and optimistic; they realize that they
will be the ultimate beneficiaries of any potential business model changes.
—The information and knowledge-sharing culture supports the enterprise’s competitive
strategy and provides the energy to sustain
this by exploiting fully the group and the individual potential.
Shared learning:
—The enterprise realizes a high return from its
commitment to its human resources.
—There is a constant stream of improvement
within the enterprise.
G. Xirogiannis et al.
Knowledge and Process Management
—The entire enterprise becomes increasingly
receptive to internal changes, since the benefit
can be easily demonstrated to individual business units.
Shared information:
—All business units and individuals have the
necessary information needed to set clearly
their objectives and priorities.
—Senior management can control effectively all
aspects of business model changes.
—The enterprise reacts rapidly to threats and
opportunities fully utilizing benefits from KM.
—It reinforces trust and respect throughout the
enterprise.
—It becomes easier for financial managers to
retrieve and share pieces of knowledge.
—Top management improves its capacity to integrate all incoming information for decision
making (e.g. time restrictions, other managerial engagements, information given with a
high/low level of detail).
—Top management can review more frequently
the firm’s risk measurement methodologies,
models and assumptions for various types of
risk (including operational risk).
Summarizing, preliminary experimental results
showed that FCM-based knowledge management
can be an effective and realistic back end to decision support. This is considered to be a major contribution of the proposed methodology tool to
actual KM exercises. Moreover, ex ante reasoning
of the impact of geographically dispersed activities
to the overall business model can be estimated with
a moderate start-up effort. Scenario building, on
the other hand, can be trivial once the skeleton
FCMs have been established.
RESEARCH ARTICLE
cial institutions in order to provide an implementation of the cycle of knowledge flow. The proposed
methodology tool utilized the fuzzy causal characteristics of FCMs to generate a hierarchical and
dynamic network of interconnected financial performance concepts. Generic maps that supplement
the knowledge-based decision process presented a
roadmap for integrating hierarchical and FCMs
into the business model of typical financial sector
enterprises.
The proposed mechanism should not be
regarded only as an effective business modelling
support tool. Its main purpose is to drive financial
change activities rather than limit itself to qualitative simulations. Moreover, the proposed mechanism should not be seen as a ‘one-off’ decision aid. It
should be a means for setting a course for continuous improvement (Langbert and Friedman, 2002).
Future research will focus on conducting further
real-life experiments to test and promote the usability of the tool, and also to identify potential pitfalls.
Furthermore, future research will focus on the
automatic determination of appropriate fuzzy sets
(e.g. utilizing pattern recognition, mass assignments, empirical data) for the representation of linguistic variables to suit each particular financial
domain. Finally, further research will focus on
implementing backward map traversal, a form of
adbuctive reasoning (Flach and Kakas, 1998). This
feature offers the functionality of determining the
condition(s) Cij that should hold in order to infer
jk
Ck.
the desired Cj in the causal relationship Cij w!
Incorporating performance integrity constraints
reduces the search space and eliminates combinatory search explosion. Backward reasoning has
been tested extensively in other applications and
its integration in the proposed framework may
prove beneficial.
CONCLUSION
This paper presented a knowledge management
methodology tool to act as a decision support
mechanism for geographically dispersed financial
enterprises. The proposed decision aid may serve
as a back end to adaptive KM by supporting ‘intelligent’ reasoning of the anticipated financial behaviour. By using FCM, the proposed mechanism
drew a causal representation of financial performance principles; it simulated the operational efficiency of distributed organizational models with
imprecise relationships and quantified the impact
of the geographically dispersed activities to the
overall business model.
The underlying research addressed the problem
of information capture and representation in finan-
Fuzzy Cognitive Maps
REFERENCES
Axelrod R. 1976. Structure of Decision: The Cognitive Maps
of Political Elites. Princeton University Press: Princeton,
NJ.
Bourne M, Mills J, Wilcox M, Neely A, Platts K. 2000.
Designing, implementing and updating performance
measurement systems. International Journal of Operations and Production Management 20: 754–771.
Craiger JP, Goodman DF, Weiss RJ, Butler A. 1996. Modeling organizational behavior with fuzzy cognitive
maps. Journal of Computational Intelligence and Organisations 1: 120–123.
Dickerson JA, Kosko B. 1997. Virtual worlds as fuzzy
cognitive maps. In Fuzzy engineering, Vol. 3, Kosko B
(ed.). Prentice-Hall: Upper Saddle River, NJ; 125–141.
Diffenbach J. 1982. Influence diagrams for complex strategic issues. Strategic Management Journal 3: 133–146.
153
RESEARCH ARTICLE
Flach PA, Kakas A. 1998. Abduction and Induction in AI:
report of the IJCAI97 workshop. Logic Journal of the
Interest Group on Pure and Applied Logic 6(4): 651–656.
Georgopoulos V, Malandraki G, Stylios C. 2002. A fuzzy
cognitive map approach to differential diagnosis of
specific language impairment. Journal of Artificial Intelligence in Medicine 679: 1–18.
Hagiwara M. 1992. Extended fuzzy cognitive maps. In
Proceedings of the 1st IEEE International Conference on
Fuzzy Systems, New York; 795–801.
Hong T, Han I. 2002. Knowledge based data mining of
news information of the internet using cognitive
maps and neural networks. Journal of Expert Systems
with Applications 23(1): 1–8.
Irani Z, Hlupic V, Baldwin LP, Love PED. 2002. Reengineering manufacturing processes through simulation modeling. Journal of Logistics Information Management 13(1): 7–13.
Johnson RJ, Briggs RO. 1994. A model of cognitive information retrieval for illstructured managerial problems
and its benefits for knowledge acquisition. In 27th
Annual Hawaii International Conference on System
Sciences, Hawaii, 191–200.
Kaplan RS, Norton DP. 1996. Using the balanced scorecard as a strategic management system. Harvard Business Review January/February: 75–85.
Kaplan RS, Norton DP. 2001. Leading change with the
balanced scorecard. Financial Executive 17: 64–66.
Kaufmann A. 1975. Introduction to the Theory of Fuzzy Subsets: Fundamental Theoretical Elements. Academic Press:
New York.
Klein JC, Cooper DF. 1982. Cognitive maps of decision
makers in a complex game. Journal of Operation Research
Society 33: 63–71.
Kosko B. 1986a. Differential hebbian learning. In AIP
Conference Proceedings, Vol. 151; 265–270.
Kosko B. 1986b. Fuzzy cognitive maps. Journal of ManMachine Studies 24: 65–75.
Kosko B. 1991. Neural Networks and Fuzzy Systems.
Prentice Hall: Englewood Cliffs, NJ.
Kosko B. 1998. Hidden patterns in combined and adaptive knowledge networks. International Journal of
Approximate Reasoning 2: 377–393.
Kwahk KY, Kim YG. 1999. Supporting business process
redesign using cognitive maps. Decision Support Systems 25(2): 155–178.
Langbert M, Friedman H. 2002. Continuous improvement in the history of human resource management.
Journal of Management Decision 40(8): 782–787.
Lee KC, Kim HS. 1997. A fuzzy cognitive map-based bidirectional inference mechanism: an application to
stock investment analysis. Journal of Intelligent Systems
in Accounting Finance and Management 6(1): 41–57.
Lee KC, Kim HS. 1998. Fuzzy implications of fuzzy cognitive map with emphasis on fuzzy causal relationship
and fuzzy partially causal relationship. Journal of Fuzzy
Sets and Systems 3: 303–313.
Lee KC, Kim JS, Chung NH, Kwon SJ. 2002. Fuzzy
cognitive map approach to web-mining inference
154
Knowledge and Process Management
amplification. Journal of Expert Systems with Applications
22: 197–211.
Lee KC, Kwon OB. 1998. A strategic planning simulation
based on cognitive map knowledge and differential
game. Journal of Simulation 7(5): 316–327.
Liu ZQ. 2000. Fuzzy Cognitive Maps: Analysis and Extension. Springer: Tokyo.
Liu ZQ, Satur R. 1999. Contexual fuzzy cognitive map
for decision support in geographical information systems. Journal of IEEE Transactions on Fuzzy Systems 7:
495–507.
Ndouse TD, Okuda T. 1996. Computational intelligence
for distributed fault management in networks using
fuzzy cognitive maps. In IEEE International Conference:
Communication Converging Technology Tomorrow’s Application, New York; 249–259.
Noh JB, Lee Lee KC, Kim JK, Lee JK, Kim SH. 2000. A
case-based reasoning approach to cognitive mapdriven tacit knowledge management. Journal of Expert
Systems with Applications 19: 249–259.
Nonaka I, Takeushi H. 1994. The Knowledge Creating Company. Oxford University Press: Oxford.
Pelaez CE, Bowles JB. 1995. Applying fuzzy cognitive
maps knowledge representation to failure modes effect
analysis. In IEEE Annual Reliability Maintainability Symposium, New York; 450–456.
Perusich K. 1996. Fuzzy cognitive maps for political
analysis. In International Symposium on Technology
and Society: Technical Expertise and Public Decisions,
New York; 369–373.
Ramaprasad A, Poon E. 1985. A computerised interactive
technique for mapping influense diagrams (MIND).
Strategic Management Journal 6(4): 377–392.
Russell B. 1989. Wisdom of the West. Crescent Books: New
York.
Schneider M, Schnaider E, Kandel A, Chew G. 1995. Constructing fuzzy cognitive maps. In IEEE Conference on
Fuzzy Systems, New York; 2281–2288.
Silva PC. 1995. New forms of combinated matrices of fuzzy cognitive maps. In IEEE International Conference on
Neural Networks, New York; 71–86.
Spencer JC, Grant RM. 1996. Knowledge and the form:
overview. Strateigc Management Journal 17(1): 89–107.
Stylios CD, Georgopoulos VC, Groumpos PP. 1997. Introducing the theory of fuzzy cognitive maps in distributed systems. In 12th IEEE International Symposium on
Intelligent Control, Istanbul, Turkey.
Valiris G, Glykas M. 2000. A case study on reengineering
manufacturing processes and structures. Journal of
Knowledge and Process Management 7(1): 20–28.
Xirogiannis G, Stefanou J, Glykas M. 2004. A fuzzy cognitive map approach to support urban design. Journal
of Expert Systems with Applications 26(2): 257–268.
Zadeh LA. 1965. Fuzzy Sets. Journal of Information and
Control 8: 338–353.
Zhang WR, Wang W, King RS. 1994. A-pool: an agentoriented open system for distributed decision process
modeling. Journal of Organizational Computing 4(2):
127–154.
G. Xirogiannis et al.