Predictive, Plan-Based Methodologies
Baselines
The scope baseline has three components: the project scope statement, the work breakdown structure (WBS), and the WBS dictionary. The WBS decomposes deliverables into work packages that can be estimated, assigned, and controlled; it is deliverable-oriented, not an organizational chart. Schedule baselines come from network diagrams and critical path analysis; cost baselines come from estimating and budgeting.
Critical Path
The critical path is the longest path through the network and therefore determines the shortest possible project duration. Activities on it have zero total float, so any delay there delays the project. Crashing adds resources to critical-path activities and usually raises cost; fast tracking overlaps activities and usually raises risk. Trap: a path with many activities is not automatically critical - path length, not activity count, decides.
Earned Value
Earned value compares planned value (PV), earned value (EV), and actual cost (AC). SV = EV − PV; CV = EV − AC; SPI = EV ÷ PV; CPI = EV ÷ AC. Negative variances and indices below 1.0 are unfavorable. Rule of thumb: EV always sits in the numerator; the comparison term sits in the denominator.
Change Control and Risk
No change enters a baseline without integrated change control: request, assess impact, decide (approve, reject, defer), update plans and documents, then communicate. Risks are uncertain events logged in a risk register with probability, impact, and an owner; threat responses are avoid, transfer, mitigate, and accept, while opportunity responses are exploit, share, enhance, and accept. A risk that has occurred becomes an issue. Trap: contingency reserve covers known risks and is managed by the project manager; management reserve covers unknown unknowns and needs sponsor approval.
Worked example: PV = 100, EV = 90, AC = 120, so SV = −10 (behind schedule), CV = −30 (over budget), SPI = 0.90, CPI = 0.75.