GSOE9820 · Engineering Project Management
Selecting PM Methods: Predictive vs Agile
This chapter teaches CLO 3 — the spectrum from predictive (plan-driven, scope fixed up front) to iterative/agile (scope re-formulated repeatedly) and how to select methods to fit a project's size, technical rigour, risk appetite, complexity and scope certainty. Selection reasoning is examined in the Knowledge Quiz and must be justified in the Task 2 PMP (why the chosen methods suit the project) and defended in the interview.
What this chapter covers
- 01The lifecycle spectrum: predictive (waterfall) → iterative → incremental → adaptive/agile
- 02Predictive: scope, schedule and cost defined early; change controlled; scope formulated up front — suits low-uncertainty engineering work
- 03Adaptive/agile: scope formulated repeatedly through the project; short feedback loops — suits high-uncertainty, evolving requirements
- 04Selection factors: project size, technical rigour, risk appetite, complexity, and how well scope is known (CLO 3)
- 05The Agile Manifesto's four values (individuals, working product, collaboration, responding to change)
- 06Scrum roles, artefacts and events; velocity for forecasting
- 07Kanban: a visual board with Work-In-Progress limits and pull-based flow
Recommend a methodology for two contrasting mini-briefs
- +1State the selection lens. Weigh size, technical rigour, risk appetite, complexity and how well scope is known. Well-understood, contract/procurement-heavy work with fixed scope points to predictive; uncertain, evolving requirements point to iterative/agile.
- +1Brief A → predictive (plan-driven). Justifying factors: (1) scope is well understood and fixed to an engineering specification, so it can be defined up front and change controlled; (2) heavy subcontracting to strict standards is managed through specifications and procurement, which suits a plan-driven approach with a fixed deadline.
- +1Brief B → adaptive/agile. Justifying factors: (1) the exact features are uncertain and will emerge from user testing, so scope must be re-formulated repeatedly rather than fixed at the start; (2) short feedback loops (sprints, working increments) let the team learn and adjust, which fits high-uncertainty, first-of-its-kind work.
- +1Add the nuance. The choice is a spectrum, not a binary: Brief B could run agile delivery within an overall predictive budget/schedule envelope (a hybrid), and Brief A might use iterative reviews for a novel sub-component. The decision follows the dominant uncertainty in each project.
Key terms
- Predictive (waterfall) life cycle
- An approach where scope, schedule and cost are defined early and change is controlled; scope is formulated up front. Suits well-understood, low-uncertainty engineering work, often with large chunks subcontracted via specifications.
- Adaptive / agile life cycle
- An approach where scope is formulated repeatedly throughout the project, with requirements emerging through short feedback loops. Suits high-uncertainty, fast-changing work.
- Iterative / incremental
- Middle-of-the-spectrum approaches: iterative elaborates the scope through repeated cycles; incremental delivers the product in successive usable pieces.
- Method selection (CLO 3)
- Choosing the life cycle and techniques to fit the project by weighing size, technical rigour, risk appetite, complexity and how well scope is known up front, then justifying the choice.
- Scrum
- An agile framework with roles (Product Owner, Scrum Master, Development Team), artefacts (Product Backlog, Sprint Backlog, Increment) and time-boxed events (Sprint, Sprint Planning, Daily Scrum, Review, Retrospective); velocity forecasts throughput.
- Kanban
- A visual-workflow method using a board (To Do / In Progress / Done) with Work-In-Progress limits and pull-based flow to optimise cycle time and throughput.
Selecting PM Methods: Predictive vs Agile FAQ
How do I choose between predictive and agile?
Judge how well the scope is known and how much it will change, alongside the project's size, technical rigour, risk appetite and complexity. Fixed, well-understood, standards- and procurement-heavy work suits a predictive (plan-driven) approach where scope is set up front; uncertain, emergent work suits an adaptive/agile approach where scope is re-formulated through short feedback loops. Many real projects are hybrids.
Is agile always the modern, better choice?
No. The examined skill (CLO 3) is fitting the method to the project, not preferring one. For a bridge refurbishment to a fixed specification, a predictive approach is the right answer; for a first-of-its-kind product with emergent requirements, agile is. An answer that just favours agile misses the mark.
What are the core parts of Scrum I should know?
The three roles (Product Owner, Scrum Master, Development Team), the three artefacts (Product Backlog, Sprint Backlog, Increment) and the events (the time-boxed Sprint with a Daily Scrum, plus Sprint Planning, Review and Retrospective). Velocity — work completed per sprint — is used to forecast. For this course you need the shape and vocabulary rather than deep practice.
Where is method selection assessed?
In the Knowledge Quiz as recall/scenario questions, and in the Task 2 PMP, where you must justify why your chosen methods suit the project, and the interview, where you defend that choice. Because it is CLO 3, expect to be asked to reason about fit rather than to define agile.
Exam move
Frame this chapter as a decision skill, not a doctrine. Practise recommending predictive vs agile for pairs of contrasting mini-briefs (a fixed-spec engineering job vs an emergent-requirements product), always giving two concrete justifying factors drawn from the selection lens: size, technical rigour, risk appetite, complexity, and how well scope is known. Rehearse resisting the "agile is better" trap — the mark is for fit. Keep a compact reference of the Agile Manifesto's four values and the Scrum roles/artefacts/events so you can answer recall items quickly, and be able to sketch a Kanban board with WIP limits. For the PMP and interview, prepare a short justification of why your project's dominant uncertainty led to your chosen method (including a hybrid, if that is the honest answer). Ask Sia to give you fresh briefs and check whether your recommendation and factors hold together.
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