Condensing & expanding networks improves accuracy, eliminates excessive details, and produces a summary network for review & use. 5 mins read.

Network Diagram Condensation

Network diagrams that are in general too detailed are not only expensive to develop but costly to maintain. Inevitably this results in the network diagram and associated schedule being discarded early in the life of the project leaving the team to work on the fly and being unable to provide accurate measures of status, performance or forecasts.

Instead condensed network diagrams are usually best, i.e. rather than several hundreds of activities a network diagram can be reduced to a few dozen activities without distorting logic. Such a summary project overview can be presented for review by senior management, a customer, or other interested audiences along with informing the project team.

If your project network diagram and associated schedule do not adequately inform, then the chances of project success are severely diminished.

In general, a safe rule of condensation is that groups of activities independent of other activities may be condensed without distorting the network logic. For example, consider Figure 1 below.

In this network, three independent activity groups may be condensed, as shown in Figure 2 below. Note activities in series have been combined while in one case two activities in parallel, G and L were combined. Importantly, all the dependency relationships in the original diagram still hold. This is very important when condensing networks, for it is very easy to introduce false or misleading dependencies.

Network Expansion

The reverse is also true, where sometimes more detail is needed to better isolate and manage risk, else to better control and manage individual scarce resources – time, effort, money, human, equipment, materials etc.

Network Level of Detail

When expanding, condensing or eliminating activities, consider the following:

1. Who will use the network, and what are their interests and span of control?
2. Is it feasible to expand the activity into more detail?
3. Are there separate skills, facilities or areas of responsibility involved in the activity, which could be cause for more detail?
4. Will the accuracy of the logic or the time estimates be affected by more or less detail

Cyclical Networks

Whenever a project involves several cycles of a group of activities, consider the following:

1. Develop a comprehensive network of the group of activities.
2. Condense the detailed network into a summarised version.
3. Use the condensed network in the cycles that compromise the entire project network.

The purpose of the comprehensive network is to develop an efficient plan for the group of activities that will be repeated and to derive accurate time, effort and duration estimates for the condensed version. The function of the condensed version is network economy since repetition of the comprehensive network would be costly in drafting time and would unnecessarily complicate and enlarge the entire project network.

Summary

Although the preparation of the network is only the first phase in developing a project, many project managers report this phase provides the most significant benefits. They feel that preparing the network caused them to think through the project more thoroughly than ever before, forcing them to do a more thorough job of advanced planning. Consequently, a great deal of useful information is included in the completed network, and the proper processing and utilisation of this information provides substantial additional benefits not only to the project manager but also to all other groups engaged in the project effort.

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Learn More

If you would like to know more about leveraging data-driven actionable insights for your project portfolio, then feel free to contact me on itierney@pminsight.com.au.