Section: Volume D
Explanation:
6.5.2.4 Three-Point Estimating
The accuracy of single-point activity duration estimates may be improved by considering estimation uncertainty and risk. This concept originated with the program evaluation and review technique (PERT).
PERT uses three estimates to define an approximate range for an activity's duration:
Most likely (tM). This estimate is based on the duration of the activity, given the resources likely to be

assigned, their productivity, realistic expectations of availability for the activity, dependencies on other participants, and interruptions.
Optimistic (tO). The activity duration based on analysis of the best-case scenario for the activity.

Pessimistic (tP). The activity duration based on analysis of the worst-case scenario for the activity.

Depending on the assumed distribution of values within the range of the three estimates the expected duration, tE, can be calculated using a formula. Two commonly used formulas are triangular and beta distributions.
The formulas are:
Triangular Distribution. tE = (tO + tM + tP) / 3

Beta Distribution (from the traditional PERT technique). tE = (tO + 4tM + tP) / 6

Duration estimates based on three points with an assumed distribution provide an expected duration and clarify the range of uncertainty around the expected duration.

Section: Volume D
Explanation:
3.7 Closing Process Group
The Closing Process Group consists of those processes performed to conclude all activities across all Project Management Process Groups to formally complete the project, phase, or contractual obligations. This Process Group, when completed, verifes that the defined processes are completed within all of the Process Groups to close the project or a project phase, as appropriate, and formally establishes that the project or project phase is complete.
This Process Group also formally establishes the premature closure of the project. Prematurely closed projects may include, for example: aborted projects, cancelled projects, and projects having a critical situation. In specific cases, when some contracts cannot be formally closed (e.g. claims, termination clauses, etc.) or some activities are to be transferred to other organizational units, specific hand-over procedures may be arranged and finalized.
At project or phase closure, the following may occur:
Obtain acceptance by the customer or sponsor to formally close the project or phase,

Conduct post-project or phase-end review,

Record impacts of tailoring to any process,

Document lessons learned,

Apply appropriate updates to organizational process assets,

Archive all relevant project documents in the project management information system (PMIS) to be used as

historical data,
Close out all procurement activities ensuring termination of all relevant agreements, and

Perform team members' assessments and release project resources.

Section: Volume E
Explanation/Reference:

Section: Volume D
Explanation:
Monitoring and Controlling Process Group
4.4 Monitor and Control Project Work
4.5 Perform Integrated Change Control
5.5 Validate Scope
5.6 Control Scope
6.7 Control Schedule
7.4 Control Costs
8.3 Control Quality
10.3 Control Communications
11.6 Control Risks
12.3 Control Procurements
13.4 Control Stakeholder Engagement
Process: 7.4 Control Costs
Definition: The process of monitoring the status of the project to update the project costs and managing changes to the cost baseline.
Key Benefit: The key benefit of this process is that it determines the cost baseline against which project performance can be monitored and controlled.
Inputs
1. Project management plan
2. Project funding requirements
3. Work performance data
4. Organizational process assets
Tools & Techniques
1. Earned value management
2. Forecasting
3. To-complete performance index (TCPI)
4. Performance reviews
5. Project management software
6. Reserve analysis
Outputs
1. Work performance information
2. Cost forecasts
3. Change requests
4. Project management plan updates
5. Project documents updates
6. Organizational process assets updates