Some Basic Considerations on the Design and the Interpretation of Indicators. . .
9
and at last, level 3 broadens the functionality by permitting n inputs of level-2-type
mathematically combined to an aggregated level-3-indicator. Of special interest is
the structure of the mathematical mapping calculating from n values one.
Two degrees of freedom offers this mapping to the user: First, the possibility
to give the measured parameter values an additional weight before composition.
Second, the kind of functional composition of the n input parameters itself.
These two degrees of freedom influence the design of a hierarchically aggregated
indicator essentially. After the following, more procedural section concerning the
workflow for building indicators, Sect. 4 will focus on the design of a complex,
hierarchically structured indicator and will discuss weights and composition in some
more detail.
2.3 Fitting Structural Alternatives to the Application Types
Before we dedicate ourselves to the workflow with the design of an indicator in the
3rd section, a short comparison between the levels just explained and the typical
application fields from the previous section should be made at this point.
The selection of suitable criteria is always connected with the specification of a
scale (level 1) and in the vast majority of cases additional classes are formed on this
scale which correspond to level 2 (judging). Thus the application fields “Warnings”
and “Decisions between alternatives” can be treated. For system optimization,
it is necessary that the indicator value be designed in such a way that a new
value assignment for the manipulated variables is constructively possible from the
current value. In addition to judging, the indicator must also constructively allow
the calculation of feedback on the input variables of the system. In the case of
optimization, it is sufficient to consider this system as a black box under observation.
This changes, if the claim of the investigation lies in the modelling of the real
system. Then it is not sufficient to observe and visualize the current values of system
variables as indicator values; rather, in the sense of a glass box, knowledge about
the static and dynamic relationships between the observed variables is necessary.
Consequently, a pure indicator system cannot replace a real model of a system.
3 The Workflow for Building Indicators
If the focus lies on how to get an indicator, it will be essential to bring the
corresponding workflow to mind and reflect its steps in detail. The Fig. 3 shows
the actions in green and the resulting objects in blue colour.
Step 1: scope and borders
The first step is the decision, which model quantities among the complete set
(given by the system or the model) are of interest for the indicator objective. Thus,
9
and at last, level 3 broadens the functionality by permitting n inputs of level-2-type
mathematically combined to an aggregated level-3-indicator. Of special interest is
the structure of the mathematical mapping calculating from n values one.
Two degrees of freedom offers this mapping to the user: First, the possibility
to give the measured parameter values an additional weight before composition.
Second, the kind of functional composition of the n input parameters itself.
These two degrees of freedom influence the design of a hierarchically aggregated
indicator essentially. After the following, more procedural section concerning the
workflow for building indicators, Sect. 4 will focus on the design of a complex,
hierarchically structured indicator and will discuss weights and composition in some
more detail.
2.3 Fitting Structural Alternatives to the Application Types
Before we dedicate ourselves to the workflow with the design of an indicator in the
3rd section, a short comparison between the levels just explained and the typical
application fields from the previous section should be made at this point.
The selection of suitable criteria is always connected with the specification of a
scale (level 1) and in the vast majority of cases additional classes are formed on this
scale which correspond to level 2 (judging). Thus the application fields “Warnings”
and “Decisions between alternatives” can be treated. For system optimization,
it is necessary that the indicator value be designed in such a way that a new
value assignment for the manipulated variables is constructively possible from the
current value. In addition to judging, the indicator must also constructively allow
the calculation of feedback on the input variables of the system. In the case of
optimization, it is sufficient to consider this system as a black box under observation.
This changes, if the claim of the investigation lies in the modelling of the real
system. Then it is not sufficient to observe and visualize the current values of system
variables as indicator values; rather, in the sense of a glass box, knowledge about
the static and dynamic relationships between the observed variables is necessary.
Consequently, a pure indicator system cannot replace a real model of a system.
3 The Workflow for Building Indicators
If the focus lies on how to get an indicator, it will be essential to bring the
corresponding workflow to mind and reflect its steps in detail. The Fig. 3 shows
the actions in green and the resulting objects in blue colour.
Step 1: scope and borders
The first step is the decision, which model quantities among the complete set
(given by the system or the model) are of interest for the indicator objective. Thus,