Process Definition

The natural progression from sequencing and estimating activities is to determine how much labor, or time, each activity will take.  Costs associated with time will impact activity estimation in PMBOK Guide 6.4.  Will it take one shift? Two? Perhaps more?  This process is an essential input to the developing the scheduling process and will require input from team leaders and experience professions with these types of activities.  

Figure 13. Estimate Activity Durations: Inputs, Tools and Techniques, and Outputs. Reprinted from "A Guide to the Project Management Body of Knowledge (PMBOK Guide), 5th Edition" by Project Management Institute, 2013, p. 166. Copyright 2013 by Project Management Institute, Inc. Reprinted without permission.

Process Assessment

Project activity durations can take more time than estimated, especially with an activity that is unfamiliar.  This process typically defines itself as the activity unfolds.  Example:  HP-2888 encountered a bird strike.  Originally estimated at 250-man hours and 1 thousand dollars in parts, the activity actually cost 362 hours and $2.5 thousand in parts.  The reason for the increase was the same most unknown activities; as the work progressed, the process unfolded into more work than could have been determined without disassembly of the affected area.  Activity estimation is often based on the best information and experience available.  Risk will come with these types of estimations.

ARTIFACTS

1. Risk Register: As an input, to the estimate activities duration process, the risk register identifies those risk items and their impact on the project and activity durations.
2. Analogous Estimating Technique: PMGT 614 Blog 3.3 explains the ease of this technique as it is based upon a previous estimate for the same type of work.
3. Contingency Theories: PMGT 611 WBS 8 lessons learned essay visits the importance of leadership and their ability to consider contingency theories when estimating activity duration. This technique ensures leadership takes into account risk factors and their probable impact on the project schedule.