|6.1 Plan Schedule Management
|The process of establishing the policies, procedures, and documentation for planning, developing, managing, executing, and controlling the project schedule.
|6.2 Define Activities
|The process of identifying and documenting the specific actions to be performed to produce the project deliverables
|6.3 Sequence Activities
|The process of identifying and documenting relationships among the project activities.
|6.4 Estimate Activity Resources
|The process of estimating the type and quantities of material, human resources, equipment, or supplies required to perform each activity.
|6.5 Estimate Activity Durations
|The process of estimating the number of work periods needed to complete individual activities with estimated resources.
|6.6 Develop Schedule
|The process of analyzing activity sequences, durations, resource requirements, and schedule constraints to create the project schedule model.
|6.7 Control Schedule
|The process of monitoring the status of project activities to update project progress and manage changes to the schedule baseline to achieve the plan.
|A schedule model is
|a representation of the plan for executing the project’s activities including durations, dependencies, and other planning information, used to produce project schedules along with other scheduling artifacts.
|Some of the better known scheduling methods include
|critical path method (CPM) and critical chain method (CCM).
|Work packages are typically decomposed into smaller components called
|activities that represent the work effort required to complete the work package.
|Rolling wave planning is
|an iterative planning technique in which the work to be accomplished in the near term is planned in detail, while the work in the future is planned at a higher level. It is a form of progressive elaboration.
|Activities, distinct from milestones, have
|durations, during which the work of that activity is performed, and may have resources and costs associated with that work.
|A milestone is a
|A milestone is a significant point or event in a project
|Every activity and milestone except the first and last should be
|connected to at least one predecessor with a finish-to-start or start-to-start logical relationship and at least one successor with a finish-to-start or finish-tofinish logical relationship
|Logical relationships should be designed to
|create a realistic project schedule.
|The precedence diagramming method (PDM) is a
|technique used for constructing a schedule model in which activities are represented by nodes and are graphically linked by one or more logical relationships to show the sequence in which the activities are to be performed.
|Activity-on-node (AON) is one
|method of representing a precedence diagram. This is the method used by most project management software packages.
|A logical relationship in which a successor activity cannot start until a predecessor activity has finished. Example: The awards ceremony (successor) cannot start until the race (predecessor) has finished.
|A logical relationship in which a successor activity cannot finish until a predecessor activity has finished. Example: Writing a document (predecessor) is required to finish before editing the document (successor) can finish.
|A logical relationship in which a successor activity cannot start until a predecessor activity has started. Example: Level concrete (successor) cannot begin until pour foundation (predecessor) begins.
|A logical relationship in which a successor activity cannot finish until a predecessor activity has started. Example: The first security guard shift (successor) cannot finish until the second security guard shift (predecessor) starts.
|In PDM, finish-to-start is the most
|commonly used type of precedence relationship. The start-to-finish relationship is very rarely used
|Mandatory dependencies are
|those that are legally or contractually required or inherent in the nature of the work. Mandatory dependencies often involve physical limitations, such as on a construction project, where it is impossible to erect the superstructure until after the foundation has been built, or on an electronics project, where a prototype has to be built before it can be tested.
|Mandatory dependencies are also sometimes referred to
|as hard logic or hard dependencies
|Discretionary dependencies are
|sometimes referred to as preferred logic, preferential logic, or soft logic. Discretionary dependencies are established based on knowledge of best practices within a particular application area or some unusual aspect of the project where a specific sequence is desired, even though there may be other acceptable sequences. Discretionary dependencies should be fully documented since they can create arbitrary total float values and can limit later scheduling options. When fast tracking techniques are employed, these discretionary dependencies should be reviewed and considered for modification or removal.
|External dependencies involve a
|relationship between project activities and non-project activities. These dependencies are usually outside the project team’s control. For example, the testing activity in a software project may be dependent on the delivery of hardware from an external source, or governmental environmental hearings may need to be held before site preparation can begin on a construction project.
|Internal dependencies involve a
|precedence relationship between project activities and are generally inside the project team’s control. For example, if the team cannot test a machine until they assemble it, this is an internal mandatory dependency.
|A lead is the amount of
|time whereby a successor activity can be advanced with respect to a predecessor activity.
|A lag is the amount of
|time whereby a successor activity will be delayed with respect to a predecessor activity. For example, a technical writing team may begin editing the draft of a large document 15 days after they begin writing it.
|A project schedule network diagram is a
|graphical representation of the logical relationships, also referred to as dependencies, among the project schedule activities.
|The Estimate Activity Resources process is closely coordinated with
|the Estimate Costs process (Section 7.2).
|Bottom-up estimating is a
|method of estimating project duration or cost by aggregating the estimates of the lower-level components of the WBS. When an activity cannot be estimated with a reasonable degree of confidence, the work within the activity is decomposed into more detail. The resource needs are estimated. These estimates are then aggregated into a total quantity for each of the activity’s resources
|Analogous estimating is a
|technique for estimating the duration or cost of an activity or a project using historical data from a similar activity or project. Analogous estimating uses parameters from a previous, similar project, such as duration, budget, size, weight, and complexity, as the basis for estimating the same parameter or measure for a future project. Analogous duration estimating is frequently used to estimate project duration when there is a limited amount of detailed information about the project. Analogous estimating is generally less costly and less time consuming than other techniques, but it is also less accurate.
|Parametric estimating is
|an estimating technique in which an algorithm is used to calculate cost or duration based on historical data and project parameters. Parametric estimating uses a statistical relationship between historical data and other variables (e.g., square footage in construction) to calculate an estimate for activity parameters, such as cost, budget, and duration. For example, if the assigned resource is capable of installing 25 meters of cable per hour, the duration required to install 1,000 meters is 40 hours. (1,000 meters divided by 25 meters per hour). This technique can produce higher levels of accuracy depending upon the sophistication and underlying data built into the model. Parametric time estimates can be applied to a total project or to segments of a project, in conjunction with other estimating methods.
|Schedule network analysis is a
|technique that generates the project schedule model. It employs various analytical techniques, such as critical path method, critical chain method, what-if analysis, and resource optimization techniques to calculate the early and late start and finish dates for the uncompleted portions of project activities.
|The critical path is
|the sequence of activities that represents the longest path through a project, which determines the shortest possible project duration.
|The critical path method is used to
|calculate the amount of scheduling flexibility on the logical network paths within the schedule model.
|The critical chain method (CCM) is a
|schedule method that allows the project team to place buffers on any project schedule path to account for limited resources and project uncertainties
|The critical chain method adds
|duration buffers that are non-work schedule activities to manage uncertainty
|• Resource leveling.
|A technique in which start and finish dates are adjusted based on resource constraints with the goal of balancing demand for resources with the available supply
|A technique that adjusts the activities of a schedule model such that the requirements for resources on the project do not exceed certain predefined resource limits.
|• What-If Scenario Analysis
|What-if scenario analysis is the process of evaluating scenarios in order to predict their effect, positively or negatively, on project objectives.
|A technique used to shorten the schedule duration for the least incremental cost by adding resources.
|A schedule compression technique in which activities or phases normally done in sequence are performed in parallel for at least a portion of their duration.
|A schedule baseline is the
|approved version of a schedule model that can be changed only through formal change control procedures and is used as a basis for comparison to actual results.