The schedule management plan documents how you will define, monitor, control, and change the project schedule. It is the only output of the Plan Schedule Management process.
As you can see in the diagram below, the define activities and sequence activities are the first two process is in the sequence.
Estimate activity resources determines the resource requirements and the quantity of resources needed for each schedule activity. You can often carry out this process at the same time as the estimate activity duration process.
If you work in an organisation where the same resource pool is used for each project, you will already know that people skill sets and availability so you can perform this process at the same time you are creating the project schedule.
This is also true for where the material resources are similar for every project.
Estimate activity durations is a process you’ll perform for most projects on which you will work.
One of the most powerful techniques here is the use of PERT estimates. These provide estimates with a high degree of reliability particularly on projects that have not been undertaken before or that involve complex processes or scope.
I have created a spreadsheet template to automatically calculate these estimates and use it for each project. The PERT estimating technique records the most likely, pessimistic, and optimistic estimates.
You can now plug the activity list, resources, estimates, and successor and predecessor tasks into the schedule. You are then in good shape to calculate the critical path.
The define activities process uses the scope baseline, which includes the project scope statement, WBS, and WBS dictionary, to help derive activities.
Activities are used to help derive a basis for estimating and scheduling project work during the planning processes and for executing and monitoring and controlling the work of the project in later processes.
The sequence activities process takes the activities and puts them in a logical, sequential order based on the dependencies. Dependencies exist when the current activity relies on some action from a predecessor activity, or it impacts a successor activity.
Four types of dependencies exist:
The estimate activity resources process considers all the resources needed and the quantity of resources needed to perform project activities.
This information is determined for each activity and is documented in the activity resource requirements output.
Duration activities are produced as a result of the estimate activity durations process.
Activity duration estimates documents the number of work periods needed for each activity, including elapsed time.
Analogous estimating, also called Top-down estimating or gross value estimating, is one way to determine activity duration estimates.
You can also use top down techniques to estimate project durations and total project costs.
Parametric estimating techniques multiply unknown elements, such as the quantity of materials needed, by the time it takes to install or complete one units of materials.
The result is a total estimate for the activity.
Three-point estimates used to four members to calculate estimates, including triangular distribution (an average estimate based on the most likely estimates, a pessimistic estimate, and an optimistic estimate), and Beta distributions, using the PERT formula.
Reserve analysis takes schedule risk into consideration by adding a percentage of time or another work periods to the estimates just in case you run into trouble.
PERT calculates a weighted average estimate for each activity by using the optimistic, pessimistic, and most likely times. It’s then determines variances, or standard deviations, to come up with a total project duration within a given confidence range.
Work will finish within plus or minus one standard deviation 68.27 percent of the time. Work will finish within plus or minus two standard deviations 95.45 percent of the time.
Develop schedule is the process in which you assign beginning and ending dates to activities and determine their duration. You might use the critical parts methods to accomplish this.
The critical parts method (CPM), calculates early start, early finish, late start, and late finish dates. It also determines float time. All tasks with zero float on critical path tasks, where the critical path is the longest path of tasks within the project.
Schedules sometimes need to be compressed to meet promised dates or to shorten the schedule times.
Crashing looks at cost and should rule trade-offs. Adding resources to critical path tasks, or approving overtime are two ways to crash the schedule.
Fast tracking involves performing tasks or phrases in parallel that were originally schedule time to start one after the other. Crashing may change the critical path where as fast tracking does not.
Fast tracking usually increases project risk.
You can use Monte Carlo analysis in the develop schedule process to determine multiple, probable project durations.
Resource levelling is used when resources are over allocated and may create changes to the critical path and the project end date. Resource smoothing modifies activities within this floats without changing the critical path or project end date.
The project schedule presents the activities in classical form using project should rule network diagrams with dates, Gantt charts, milestone charts, and project should rule network diagrams.