Time Management

Time Management consists of the following processes. See also Knowledge Areas - Time.

Process	Project Phase
Define & Plan activities	Planning
Sequence activities	Planning
Estimate resources	Planning
Estimate duration of activities	Planning
Develop schedule	Planning
Control schedule	Monitoring & Controlling

This knowledge area is concerned with estimating the duration of the project plan activities, devising a project schedule, and monitoring and controlling deviations from the schedule.

"Hours are like diamonds, don't let them waste... Time waits for no one, no favours has he... Time waits for no one, and he won't wait for me" Jagger/Richards

Define & Plan Activities

Activity definition consists of decomposing or breaking down the work to reach a level that can be easily estimated and managed.

Sequence Activities

Activity sequencing involves structuring the activities according to the order in which they will be performed. Network diagrams are used in this process.

Network Diagrams

Network diagrams are used to display activities and their dependencies. There are two type of network diagrams:

Precedence Diagramming Method (PDM) or Activity on Node (AON)
Arrow Diagramming Method (ADM) or Activity on Arrow (AOA)

Dependencies may exist for activities which will impact when they can be scheduled. Types of dependencies between activities can be Mandatory, External, or Discretionary.

Leads & Lags are also important concepts to understand for scheduling activities to account for dependencies.

Lead - the successor activity begins before the predessor activity has completed.
Lags - the successor activity cannot start right after the end of its predecessor; it refers to inserted waiting times in between tasks.

Estimate Resources

This process involves estimating internal / external human resources (including vendors), as well as equipment and materials. It takes into account the skill sets and number of resources required for the work effort.

Estimate Duration of Activities

Analogous Estimating (Top Down) - uses historical information and expert judgement to produce an estimate.
Parametric Estimating - uses statistical information between historical data and variables to produce a more accurate estimate. It identifies the unit cost or duration and the number of units required for the project or activity. For example, past projects used 5 testers to test the application for a project of similar size/cost.
Heuristics - general principles.
Three Point Estimates - estimate based on best, most likely, and worst case scenarios.

PERT (Program Evaluation and Review Techniques)

PERT is a network model that allows for randomness in activity completion. From PMBOK, PERT uses a weighted average duration estimate to calculate activity durations. PERT Formulas

Develop Schedule

Critical Path - longest duration path through a network diagram. The Critical Path is the shortest possible time it will take to complete the project.

CPM (Critical Path Method) - From PMBOK, CPM "calculates a single, deterministic early start and finish date for each activity based on specified sequential network logic and a single duration estimate."

Float - amount of time a task can be delayed without delaying the project. Also known as slack. Note that tasks on the critical path have zero float.

Float = LF - EF = LS - ES

where

LF = Late Finish

EF = Early Finish

LS = Late Start

ES = Early Start

Schedule Techniques

Crashing - assign additional resources to tasks and decrease the duration required for those tasks
Schedule Compression - shorten the project schedule duration without reducing the project scope
Resource Leveling - used to balance resources throughout the duration of the project to ensure proper allocation
Fast Tracking - perform some activities concurrently that were originally scheduled sequentially to shorten project time
Critical Chain Method - alternative to critical path analysis; emphasis on resources and activities

Control Schedule

This process involves monitoring project status and controlling changes to the project schedule. Progress reporting is used to communicate the overall project schedule to stakeholders.

Additional Information

Time Management on Wikipedia

PERT on Wikipedia

Network Diagrams on Wikipedia

Time Management Sample Questions