Which one of the following is NOT considered for the estimation of activity duration?

Explanation:

Estimation of Activity Duration or Time Estimation:

• A project is composed of many diversified activities which contribute to its completion.
• An important characteristic of any project is its duration. As its effectiveness and economy are often dependent on the project duration.
• The total project duration depends on the time taken by each activity.
• Estimation of time required for any activity requires wide experience of similar activities.
• Evaluate activities one at a time, independently of all others.
• For each activity, assume a normal level of manpower and or equipment.
• If time units of working days are being used, assume a normal workday.
• Normal weather conditions are considered for the estimation of the duration of each activity.
• Estimation of these time estimates can be done in two ways:

1. Deterministic approach: The Planner has enough knowledge about the activity and gives a single estimate of the duration which is almost accurate.
2. Probabilistic Approach: The planner does not have much idea about the activity as there is little or no past history about it. The limits within which the duration will lie are estimated.

• The time estimate of an activity has a greater range of variation and hence greater uncertainty. therefore probabilistic approach is used.
• Time estimate of an activity has a narrow range of variation and hence in this case time estimate is deterministic.
• PERT follows the probabilistic approach and absorbs the uncertainties into the time estimates for activity and project durations.
• CPM follows the deterministic approach.

​Hence option (3) is correct.