A project is, as relates to a person, any activity undertaken
to change some current state of something into a desired state.
In this sense, the Person to Project relation may be represented
by the standard Balancing Loop
Archetype.
The difference between the Desired State and the Current
State creates a Gap. This Gap then influences
me to take Action to move the Current State toward
the Desired State. As the Current State becomes
closer and closer to the Desired State the Gap becomes
smaller and smaller, thus influencing less and less Action
on my part. When the Current State finally equals the Desired
State the Gap is reduced to zero and there is no more
influence for Action.
The following represents an implementation of this system in Vensim
PLE.
Running this model with some specific values might produce
a transition which looks as follows:
This diagram depicts an initial state where the Desired
State and the Current State are equal. Somewhere around
the 5th month the Desired State is changed to a new value.
This new Desired State influences Action to be taken
to transition the Current State in the direction of the
Desired State. The rate of transition is dependent on the
amount of Action applied.
There seems to be an implication inherent in this structure. Since
there is a direct relation between the size of the Gap
and the amount of Activity, as the Gap becomes smaller
the amount of Activity decreases. This might provide some
insight as to why projects often seem to go slower and slower
as they get closer and closer to completion. Strange as it may
seem, as many times as I've built this model, I never thought
about this implication until I was writing this description. Maybe
I'm just slow sometimes.
If you have a copy of Vensim PLE you can download this model:
persproj02.mdl (2k). If you don't have
a copy of Vensim PLE you can download a * free * personal use
copy for Mac or PC from Ventana
Systems.
This example could continue to be elaborated as there are numerous
other relevant influences which are part of the real world version
of this. Once the learner reaches the end of this segment they
could then choose from a number of relations associated with Person
or Project.