130
V. R. Vargas et al.
as a helpful tool to tackle problematic situations arising from the issues. The world
outside seems highly interconnected forming wholes; therefore, it seems that the
concept ‘system’ can help us to cope with the intertwined reality we perceive. Figure 1
shows the basic structure of Soft Systems Methodology.
3.3 Measuring the Performance of a System with SSM:
CATWOE, the Transformation Process and the Three
‘Es’: Efficacy, Efficiency and Effectiveness
The issue of measuring the performance of a system is first mentioned by Checkland
with relation to the attributes of the formal system model (Checkland 1981). The
formal system model, ‘S’, is described as a device that can be used as a way of
validating the model of the system currently being studied: “S is a formal construct
aimed at helping the building of conceptual models which are themselves formal”
(Checkland 1981: 174). Checkland lists a number of conditions for ‘S’ to be formal,
one of these conditions is that ‘S’ should be measured; ‘S’ is said to have a measure
of performance capable “to signal progress or regress in pursuing purposes or trying
to achieve objectives” (Checkland 1981: 174).
CATWOE is the mnemonic of the six crucial characteristics which should be
included in a well-formulated root definition.
C ‘Customers’—the beneficiaries or victims of the transformation process.
A ‘Actors’—those who would undertake the transformation process.
T ‘Transformation’—the conversion of input to output.
W ‘Weltanschauung’ ‘worldview’—the worldview that makes this transformation
meaningful.
O ‘Owners’—those who could stop the transformation.
E ‘Environmental constraints’—elements outside the system which are taken as
given.
From these elements, T is at the core of any root definition encapsulating the
concepts that inputs are transformed into outputs as the root definition suggests.
T, the transformation process, is the CATWOE element on which Checkland
elaborates the notion of measuring the performance of the system. According to
Checkland, at the most fundamental level, any purposeful activity may be expressed
through a Transformation Process which “changes or transforms some input into
some output”. In other words, for the Transformation to be relevant, Inputs are
present in Outputs but in a changed state. Then if the Input is abstract (e.g. ‘need
for nursing services’) then the Output must also be abstract (e.g. ‘need met’). If the
Input is concrete (e.g. ‘a patient’) then the Output must be concrete (e.g. ‘a treated
patient’). This distinction is important because it helps to differentiate between the
resources and the inputs of the system. SSM also stresses the fact that there are many
ways of expressing a purposeful activity; more ways of expressing the activity in
terms of Input-Transformation-Output will enrich the thinking.
V. R. Vargas et al.
as a helpful tool to tackle problematic situations arising from the issues. The world
outside seems highly interconnected forming wholes; therefore, it seems that the
concept ‘system’ can help us to cope with the intertwined reality we perceive. Figure 1
shows the basic structure of Soft Systems Methodology.
3.3 Measuring the Performance of a System with SSM:
CATWOE, the Transformation Process and the Three
‘Es’: Efficacy, Efficiency and Effectiveness
The issue of measuring the performance of a system is first mentioned by Checkland
with relation to the attributes of the formal system model (Checkland 1981). The
formal system model, ‘S’, is described as a device that can be used as a way of
validating the model of the system currently being studied: “S is a formal construct
aimed at helping the building of conceptual models which are themselves formal”
(Checkland 1981: 174). Checkland lists a number of conditions for ‘S’ to be formal,
one of these conditions is that ‘S’ should be measured; ‘S’ is said to have a measure
of performance capable “to signal progress or regress in pursuing purposes or trying
to achieve objectives” (Checkland 1981: 174).
CATWOE is the mnemonic of the six crucial characteristics which should be
included in a well-formulated root definition.
C ‘Customers’—the beneficiaries or victims of the transformation process.
A ‘Actors’—those who would undertake the transformation process.
T ‘Transformation’—the conversion of input to output.
W ‘Weltanschauung’ ‘worldview’—the worldview that makes this transformation
meaningful.
O ‘Owners’—those who could stop the transformation.
E ‘Environmental constraints’—elements outside the system which are taken as
given.
From these elements, T is at the core of any root definition encapsulating the
concepts that inputs are transformed into outputs as the root definition suggests.
T, the transformation process, is the CATWOE element on which Checkland
elaborates the notion of measuring the performance of the system. According to
Checkland, at the most fundamental level, any purposeful activity may be expressed
through a Transformation Process which “changes or transforms some input into
some output”. In other words, for the Transformation to be relevant, Inputs are
present in Outputs but in a changed state. Then if the Input is abstract (e.g. ‘need
for nursing services’) then the Output must also be abstract (e.g. ‘need met’). If the
Input is concrete (e.g. ‘a patient’) then the Output must be concrete (e.g. ‘a treated
patient’). This distinction is important because it helps to differentiate between the
resources and the inputs of the system. SSM also stresses the fact that there are many
ways of expressing a purposeful activity; more ways of expressing the activity in
terms of Input-Transformation-Output will enrich the thinking.