QUERY Models, Problems and Systems (SD6996)

[SDMAIL Kim Warren]

Posted by  "Kim Warren" <Kim at strategydynamics.com>

SDMAIL Dr John P Weldon wrote:
> The 'rule' therefore needs to be substantially redefined along the lines 
> below.
> 
>     If a genuine 'problem' can be identified of smaller content and
>     scope than that of the system in which it resides, modeling shall be
>     confined to entities (below the number needed to model the system
>     itself) that can adequately explain and resolve the 'problem'. In
>     all other cases modeling of the system shall be regarded as
>     appropriate and necessary. 

I'd like to build on John's post, because I too have been puzzled by
where this mantra of 'model the problem, not the system' came from and
what its justification might be. We 'model systems' in all kinds of
ways, whether it is designing an aircraft, assessing the weather,
designing a piece of software and so on. And we use those models to
allow us to manage the resulting system, where that may be possible.
There seem to be two broad problems with just 'modeling the problem' 

1. Unless we are very careful, we may miss factors that are significant
contributors to the problem because we decide on boundaries that seem to
make sense, but are not in fact comprehensive. Consequently, we may
solve *this* occurrence of the problem, but leave the organization
exposed to recurrences that are due to different factors - e.g. we fix
service quality now by modelling and identifying how best to develop a
service-support team, but next week the problem comes back because the
sales force manages to sell a different mix of products.

2. We do not leave management with any means of continuing to manage the
system as a whole. This would seem to be like giving an aircraft pilot a
sequence of indicators and instructions to get out of a tail-spin, but
no overall control system or procedures for actually flying the plane in
general. 

I can see circumstances where modelling a problem would be valuable,
with caveats about 1 and 2 above, but would we not rather models to
provide a set of policies for managing things well so we don't get into
trouble in the first place?

Kim Warren 
Posted by  "Kim Warren" <Kim at strategydynamics.com>
posting date  Wed, 7 May 2008 08:14:32 +0100