Valid models require defined levels
A. Terry Bahill, Ferenc Szidarovszky, Rick Botta, Eric Smith · International Journal of General Systems · 2008
A common mistake in modeling systems is mixing elements of different levels in the same model. This paper explains levels, shows how levels can be obtained with decomposition techniques and gives many examples of levels in models, architectures and frameworks. Examples are given that show the confusion that results when levels are mixed. The paper shows that complex models are usually composed of many aspects. Each aspect has levels and the levels of one aspect are different from the levels of another aspect. The model must be constructed using elements of the same level for each aspect.