What-If Scenario Analysis

Thinking through potential outcomes, the What-If Scenario Analysis is a tool and technique of the Develop Schedule process and the Control Schedule process, both described in the fourth edition PMBOK®. This technique is used to estimate impacts to the project schedule if potential scenarios occur. This technique simply repeatedly asks “what if” a certain event should happen. It is useful to have more than one person’s perspective and ideas for this analysis. For example, Katy has two hours to bake three dozen cookies. She and her family are doing a What-If Scenario Analysis for this cookie baking project. “What if you burn the first batch?” asks her husband. They estimate that will extend the schedule an hour. “What if Dad is eating the cookies as fast as you can make them?” asks her daughter. They estimate that he’ll become full at a certain point, so it’ll extend the schedule half an hour. In summary, What-If Scenario Analysis simply estimates the effect that potential events may have.

Schedule Compression

It needs to be done in less time… Schedule Compression is a tool and technique of the Develop Schedule process described in the fourth edition PMBOK®. If a project needs to be completed faster than it is currently progressing, the project manager may apply a schedule compression technique. Two schedule compression techniques are crashing and fast-tracking. Crashing applies additional money and/or resources to shorten the duration of the project. This can increase risk to the project, so the trade-off should be carefully considered. Also, there some types of tasks that additional money or resources cannot shorten. Fast-tracking is the preferred method of schedule compression. Fast-tracking performs activities in parallel that are normally done sequentially. Like crashing, there can be additional risk introduced.

Here are some examples involving Katy, who is planning on making cookies tomorrow afternoon just before her dinner guests arrive so that the cookies will be warm from the oven. She discovers that her dinner guests will be arriving earlier than planned, but she can’t start making the cookies earlier, either. She applies the technique of crashing, and buys a couple more cookies sheets so that she bake three sheets of cookies at once, rather than just one sheet of cookies at a time. So, she has invested more money (to buy the extra cookie sheets) in order to shorten the duration of her cookie baking project. Typically, Katy watches the cookies the entire time they are in the oven so they don’t burn. But she decides to also apply fast-tracking and set the table for her dinner guests while the cookies are in the oven. Normally the task of setting the table would come after her cookies are taken out of the oven, but now the task of the cookies baking is done at the same time the table is being set. As you can see, there is some added risk that the cookies are more likely to burn, but she decides it is worth the trade-off to have warm cookies ready for her guests.

Develop Schedule Process

Develop Schedule is one of the 42 project management processes described in the fourth edition PMBOK®. It’s one of the six Time knowledge area processes, and one of the twenty Planning processes. The purpose of this particularly important process is to create the project schedule. This is the most important Time process, and there are more inputs and tools for the Develop Schedule process than any other Time process. The four Time processes that occur beforehand (Define Activities, Sequence Activities, Estimate Activity Resources, and Estimate Activity Durations) all contribute information that is needed to create the schedule, and the process that begins after the schedule is made (Control Schedule) monitors whether the project is on track with the schedule. In addition to the Project Scope Statement and Resource Calendars being inputs, the Time processes provide the inputs of Activity List and Activity Attributes (from Define Activities), Project Schedule Network Diagrams (from Sequence Activities), Activity Resource Requirements (from Estimate Activity Resources), and Activity Duration Estimates (from Estimate Activity Durations).

The Develop Schedule process takes all this information from these inputs concerning the activities, their needed durations and resources, and their dependencies among each other, and creates the Project Schedule. This is not a simple process. In fact, PMI (Project Management Institute) even offers a credential for scheduling professionals, the PMI-SP. Software is frequently used to make schedule creation easier, which is this process’s tool of Scheduling Tool. Leads and lags are determined, which is accounting for lead time before an activity and lag time after an activity. The Critical Path Method and Critical Chain method are two common methods of organizing individual project activities into a complete schedule. If the schedule must be compressed, there are the options of crashing (adding some type of resources) and fast-tracking (performing tasks in parallel). Of course, the primary output of this process is the Project Schedule.