Chapters 9 and 10 established a baseline plan and a schedule, respectively for the consumer market study project. Once a project actually starts, its necessary to monitor the progress to ensure that everything is going according to schedule. The key to effective project control is to measure actual progress and compare it to planned progress on a timely and regular basis and to take necessary action immediately.
LEARNING OBJECTIVES This chapter will cover the details of controlling a project and will focus mainly on the critical role of controlling the scheduling to ensure that the work gets done on time. By mastering the concepts discussed in this chapter, you should be well prepared to help control your projects.
You will become familiar with: Performing the steps in the project control process; Determining the effects of actual schedule performance on the project schedule; Incorporating project changes into the schedule; Calculating an updated project schedule; Controlling the project schedule.
PROJECT CONTROL PROCESS The project control process involves regularly gathering data on project performance, comparing actual performance to planned performance, and taking corrective actions if actual performance is behind planned performance. Figure 11.1 illustrates the steps in the project control process.
It starts with establishing a baseline plan that shows how the project scope (tasks) will be accomplished on time (schedule) and within budget (resources, costs). A regular reporting period should be established for comparing actual progress with planned progress. During each reporting period, two kinds of data or information need to be collected:
1.Data on actual performance. This includes The actual time that activities were started and/or finished The actual costs expended and committed 2.Information on any changes to the project scope, schedule, and budget. These changes could be initiated by the customer or the project team, or they could be the result of an unanticipated occurrence such as a natural disaster, a labor strike, or the resignation of a key project team member.
It should be noted that once changes are incorporated into the plan and agreed on by the customer, a new baseline plan has to be established. The scope, schedule, and budget of the new baseline plan may be different from those of the original baseline plan. It is crucial that the data and information discussed above be collected in a timely manner and used to calculate an updated project schedule and budget.
Once an updated schedule and budget have been calculated, they need to be compared to the baseline schedule and budget and analyzed for variances to determine whether a project is ahead of or behind schedule and under or over budget. If it is determined that corrective actions are necessary, however, decisions must be made regarding how to revise the schedule or the budget. These decisions often involve a trade-off of time, cost, and scope.
In general, the shorter the reporting period, the better the chances of identifying problems early and taking effective corrective actions. If a project gets too far out of control, it may be difficult to achieve the project objective without sacrificing the scope, budget, schedule, or quality. Project management is a proactive approach to controlling a project, to ensure that the project objective is achieved even when things dont go according to plan.
EFFECTS OF ACTUAL SCHEDULE PERFORMANCE Throughout a project, some activities will be completed on time, some will be finished ahead of schedule, and others will be finished later than scheduled. Actual progress– whether faster or slower than planned- will have an effect on the schedule of the remaining, uncompleted activities of the project.
Specifically, the actual finish times (AF) of completed activities will determine the earliest start and earliest finish times for the remaining activities in the network diagram, as well as the total slack. Figure 11.2 is an AIB network diagram for a simple project. This example illustrates how the actual finish times of activities have a ripple effect,altering the remaining activities earliest start and finish times and the total slack.
INCORPORATING PROJECT CHANGES INTO THE SCHEDULE Changes might be initiated by the customer or the project team, or they might be the result of an unanticipated occurrence. Here are some examples of changes initiated by the customer:
A home buyer tells the builder that the family room should be larger and the bedroom windows should be relocated. A customer tells the project team developing an information system that the system must have the capability to produce a previously unmentioned set of reports and graphics. These types of changes represent revisions to the original project scope and will have an impact on the schedule and cost.
When the customer request a change, the contractor or project team should estimate the impact on the project budget and schedule and then obtain customer approval before proceeding. If the customer approves the proposal revisions to the project schedule and budget, any additional tasks, revised duration estimates, and material and labor costs should be incorporated. Some changes involve the addition of activities that were overlooked when the original plan was developed.
Other changes become necessary because of unanticipated occurrences, such as a snowstorm that slows down construction of a building. Still other changes can result from adding more detail to the network diagram as the project moves forward. Any type of changewhether initiated by the customer, contractor, project manager– will require a modification to the plan in terms of scope, budget, and/or schedule.
UPDATING THE PROJECT SCHEDULE Network-based planning and scheduling allows project schedules to be dynamic. Because the network plan (diagram) and schedule (tabulation) are separate, they are much easier to update manually than a traditional Gantt chart. Once data have been collected on the actual finish times of completed activities and the of any project changes, an updated project schedule can be calculated.
These calculations are based on the methodology explained in Chapter 10: The earliest start and finish times for the remaining, uncompleted activities are calculated by working forward through the network, but they are based on the actual finish times of completed activities and the estimated durations of the uncompleted activities; The latest start and finish times for the uncompleted activities are calculated by working backward through the network.
As an illustration of the calculation of an updated schedule, lets consider the network diagram shown in Figure 11.3 for the consumer market study project. The network diagram in Figure 11.3 incorporates the above information. Figure 11.4 shows the updated schedule.
APPROACHES TO SCHEDULE CONTROL Schedule control involves four steps: 1.Analyzing the schedule to determine which areas may need corrective action. 2.Deciding what specific corrective action should be taken. 3.Revising the plan to incorporate the chosen corrective actions 4.Recalculating the schedule to evaluate the effects of the planned corrective actions.
If the planned corrective actions do not result in an acceptable schedule, these steps need to be repeated. The schedule analysis should include identifying the critical path and any paths of activities that have a negative slack, as well as those paths where slippages have occurred compared with the previously calculated schedule. A concentrated effort to accelerate project progress must be applied to the paths with negative slack.
Corrective actions that will eliminate the negative slack from the project schedule must be identified. Remember, the slack for a path of activities is shared among all the activities on that path. Therefore, a change in the estimated duration of any activity on that path will cause a corresponding change in the slack for that path.
When analyzing a path of activities that has negative slack, you should focus on two kinds of activities: 1. Activities that are near term (that is, in progress or to be started in the immediate future). 2.Activities that have long duration estimates. There are various approaches to reducing the duration estimates of activities.
One obvious way is to apply more resources to speed up an activity. Reducing the scope or requirements for an activity is another way to reduce its duration estimate. Increasing productivity through improved methods or technology is yet another approach to reducing activities durations. Once specific corrective actions to reduce the negative slack have been decided on, the duration estimates for the appropriate activities must be revised in the network plan.
In most cases, eliminating negative slack by reducing durations of activities will involve a trade-off in the form of an increase in costs or a reduction in scope. The key to effective schedule control is to aggressively address any paths with negative or deteriorating slack values as soon as they are identified, rather than hoping that things will improve as the project goes on. Project meetings are a good forum for addressing schedule control issues.
SCHEDULE CONTROL FOR IS DEVELOPMENT Among the changes that commonly become necessary during IS development projects are the following: Changes to input screens; Changes to reports; Changes to on-line queries; Changes to database structures;
Changes to software processing routines; Changes to processing speeds; Changes to storage capacities; Changes to business processes; Changes to software resulting from hardware upgrades or, conversely, hardware upgrades resulting from the availability of more powerful software.
AN IS EXAMPLE: ABC OFFICE DESIGNS (CONTINUED) Figure 11.5 and 11.6 show the updated network diagram and project schedule, respectively, after these changes have been incorporated. Notice that because of the above occurrences, the critical path now has a total slack of 0.
PROJECT MANAGEMENT SOFTWARE Virtually all project management software packages allow you to perform the control functions identified in this chapter. All network diagrams, tables, and reports produced by the software will be updated to reflect the most recent information.