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COLLECTION DELAY<br />

NEW information<br />

CONVERSION<br />

EFFICIENCY<br />

150 150 pieces Pieces<br />

3,000 Pieces<br />

3,000 pieces<br />

112.5 pieces<br />

2,250 pieces<br />

112.5 Pieces<br />

2,250 Pieces<br />

75 75 pieces Pieces<br />

1,500 1,500 pieces Pieces<br />

37.5 37.5 pieces Pieces<br />

750 Pieces<br />

750 pieces<br />

0 pieces<br />

0 pieces<br />

rate <strong>of</strong><br />

information gain<br />

+<br />

ability to utilize new<br />

information<br />

INITIAL INFORMATION<br />

+<br />

41<br />

0 Pieces<br />

0 Pieces<br />

0 8 16 24 32 40 48<br />

56 64 72 80 88 96 104 112 120 128 136 114 144<br />

Time (Month)<br />

Time (Month)<br />

rate <strong>of</strong> information<br />

degradation<br />

+<br />

RATE OF<br />

OBSOLESCENCE<br />

Information<br />

Dynamic behavior <strong>of</strong> Information and Knowledge<br />

Dynamic behavior <strong>of</strong> Information and Knowledge<br />

+<br />

LEARNING DELAY<br />

Information : NEW INFORMATION is constant Pieces<br />

Information: Information : NEW NEW INFORMATION INFORMATION switches is constant Pieces<br />

Knowledge : NEW INFORMATION is constant Pieces<br />

Information: NEW INFORMATION switches Pieces<br />

Knowledge : NEW INFORMATION switches Pieces<br />

Knowledge: NEW INFORMATION is constant Pieces<br />

Knowledge: NEW INFORMATION switches Pieces<br />

INITIAL KNOWLEDGE<br />

rate <strong>of</strong> knowledge<br />

change<br />

LEARNING<br />

EFFICIENCY<br />

Knowledge<br />

Comment:<br />

The simulation <strong>of</strong> the levels<br />

”Information” and ”Knowledge” is<br />

run for two cases <strong>of</strong> ”NEW<br />

INFORMATION”. In the first case<br />

”NEW INFORMATION” has a<br />

constant value <strong>of</strong> 10 Pieces/Month.<br />

In the second case it starts at +10,<br />

switches to -10 at t=36 months and<br />

returns to +10 at t=42 months<br />

(dash-dot lines). The initial value<br />

<strong>of</strong> ”Information” is 100 Pieces, and<br />

the initial value <strong>of</strong> ”Knowledge” is<br />

1000 Pieces. Due to the delays<br />

(”COLLECTION DELAY”=12<br />

months, ”TRANSFORMATION<br />

DELAY= 24 months) the effect <strong>of</strong><br />

the switch on ”Information”<br />

reaches its maximum only at<br />

approx. t=57 months, whereas its<br />

effect on ”Knowledge” is minimal.<br />

Figure 8: FSD model <strong>of</strong> the information process/system in Figure 7, with dynamic behavior for<br />

hypothetical parameter values. FSD simulation requires additional parameters (exogenous<br />

variables) that clutter the model compared with the qualitative models in Figure 7. Assumed<br />

parameter values are given in Appendix 2, Table 2-1.<br />

There are aspects that negate the advantages <strong>of</strong> FSD. First, FSD is a controversial<br />

method with a small group <strong>of</strong> practitioners, primarily at some business schools. For<br />

the present work the obscurity <strong>of</strong> FSD introduces the risk <strong>of</strong> having ideas rejected as<br />

being too enigmatic. 38 This risk is pointed out in LeFèvre, which claims that because<br />

<strong>of</strong> the unnatural appearance <strong>of</strong> FSD models they fail to capture the interest <strong>of</strong> the<br />

people who have the real knowledge <strong>of</strong> the system. Thus, knowledge extraction<br />

becomes a bottleneck and the credibility <strong>of</strong> the result is seen as quite dubious by the<br />

end-users. [Fev97] 39 Second come weaknesses in the FSD paradigm that may limit<br />

38 An example <strong>of</strong> the criticism against FSD is the claim that the treatise Limits to Growth, by<br />

Meadows et al., substitutes elaborate causal structures for missing data, and that the models lack<br />

empirical validity [And01]. A critical review <strong>of</strong> Forrester’s Urban Dynamics claims that the<br />

conclusions <strong>of</strong> the book are outright wrong (including its “counterintuitive” results), that there is a<br />

gulf between what the urban model is and what Forrester claims it to be, and that Forrester’s<br />

knowledge <strong>of</strong> cities is limited to what he has learned from the former mayor <strong>of</strong> Boston [Lee73]. A true<br />

dialogue between the differing views does not seem to have emerged, and thus in 1999 Meadows<br />

[Mea99] claims that “Forrester was right”. A systems engineering view on FSD is that it is “(…) a<br />

technique viewed with the gravest suspicion in some industrial circles, owing to its potentially<br />

imprecise approach to modelling—although it is that very imprecision which makes system dynamics<br />

potentially useful for addressing s<strong>of</strong>ter issues” [Hit92 p.22].<br />

39 A) The comment in LeFèvre [Fev97] points to different usages in the traditional FSD community,<br />

which consists mainly <strong>of</strong> individuals with background in sociology and management, and in the

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