SYE6047 Chap.7 New Quality Tools and Project Scheduling
New Quality Tools and Project Scheduling
Structure verbal complexity
The new seven quality tools are most useful when the evidence is qualitative, relationships are tangled or implementation must be planned. An affinity diagram groups many statements by natural relationship without forcing categories too early. A relations diagram then explores which issues influence others.
The first creates coherent clusters; the second makes a proposed influence structure visible.
Decompose and connect
A tree diagram moves from a broad objective to increasingly specific means or components. A matrix diagram crosses two sets of items and records the strength or existence of relationships. Matrix data analysis adds quantitative comparison to multivariate relationships.
These tools are not interchangeable: a tree asks how or what components, while a matrix asks which row items connect with which column items.
Plan sequence and risk
An arrow diagram represents activity dependencies, duration and the route that controls project completion.
The critical path is the longest duration path through the network; delaying one of its activities delays the project unless the network changes. A process decision program chart starts from a plan, anticipates what might go wrong and attaches countermeasures before execution.
Choose by the decision
Tool selection begins with the output required.
Use affinity for clustering, relations for influence, tree for decomposition, matrix for cross-relationships, arrow for scheduling, process decision for contingencies and matrix data analysis for numerical pattern reduction. The diagram organises reasoning, but its links still need knowledgeable participants and evidence.
What this chapter covers
- 01
Affinity grouping
- 02
Relations and influence
- 03
Tree decomposition
- 04
Matrix relationships
- 05
Arrow networks
- 06
Critical path
- 07
Process decision program chart
- 08
Matrix data analysis
Worked example · free
Find the path that controls completion
- 3Calculate both path durations.
- 2Identify the critical path.
- 3Assess whether shortening B changes completion.
Key terms
- Affinity Diagram
- A method for grouping many verbal statements by natural relationship.
- Relations Diagram
- A network showing proposed influence among multiple issues.
- Tree Diagram
- A hierarchy that decomposes an objective into components or means.
- Critical Path
- The longest-duration path through a dependency network that controls completion time.
- PDPC
- A planning diagram that anticipates failures and attaches countermeasures to a proposed route.
New Quality Tools and Project Scheduling FAQ
How is an affinity diagram different from a fishbone diagram?
Affinity grouping lets categories emerge from many statements. A fishbone uses a cause-oriented structure to organise possible explanations for one effect. The former is useful before the problem structure is clear. Moving too quickly to cause branches can discard observations that do not fit the team's first theory and make tentative influence look established.
Does the critical path contain the most activities?
Not necessarily. It is the path with the greatest total duration under the dependency network. A shorter path can contain more individual tasks but still have float.
When should I use a PDPC?
Use it when a proposed plan needs systematic anticipation of failure modes and countermeasures. It complements scheduling by asking what could derail each branch rather than merely when each activity occurs.
Exam move
Memorise each new tool as a verb: cluster, influence, decompose, cross, schedule, anticipate and quantify. For arrow problems, list every complete start-to-finish route and total it before naming the critical path. Then test changes by recalculating, not by intuition.
Give yourself one messy collection of interview statements and move it through the tools in order: allow affinity categories to emerge, convert selected themes into relations hypotheses, decompose an evidence-backed objective with a tree, cross tasks and owners in a matrix, and schedule dependencies with an arrow network. At every handoff, state what information changed form and which claim still needs evidence.
Define matrix symbols before filling cells, retain disagreements rather than averaging them invisibly, and check whether every required output has an owner. For a PDPC, add failure branches only where a plausible contingency and useful countermeasure can be stated. In scheduling questions, calculate slack as well as the longest route, then repeat the calculation after a duration change because the critical path can move.
