Section 6.3.1 Activity Resource Estimating: Inputs

The Activity Resource Estimating process uses the infrastructure resource availability information included in enterprise environmental factors (Section 4.1.1.3).

.2 Organizational Process Assets

Organizational process assets (Section 4.1.1.4) provide the policies of the performing organization regarding staffing and the rental or purchase of supplies and equipment that are considered during activity resource estimating. If available, historical information regarding what types of resources were required for similar work on previous projects are reviewed.

.3 Activity List

The activity list (Section 6.1.3.1) identifies the schedule activities for resources that are estimated.

.4 Activity Attributes

The activity attributes (Section 6.1.3.2) developed during the activity definition process provide the primary data input for use in estimating those resources required for each schedule activity in the activity list.

Information on which resources (such as people, equipment, and materiel) are potentially available (Sections 9.2.3.2 and 12.4.3.4) is used for estimating the resource types. This knowledge includes consideration of various geographical locations from which the resources originate and when they may be available. For example, during the early phases of an engineering design project, the pool of resources might include junior and senior engineers in large numbers. During later phases of the same project, however, the pool can be limited to those individuals who are knowledgeable about the project as a result of having worked on the earlier phases of the project.

.6 Project Management Plan

The schedule management plan is a component part of the project management plan (Section 4.3) that is used in Activity Resource Estimating.

Section 6.3.2 Activity Resource Estimating: Tools and Techniques

Many schedule activities have alternative methods of accomplishment. They include using various levels of resource capability or skills, different size or type of machines, different tools (hand versus automated), and make-or-buy decisions regarding the resource (Section 12.1.3.3).

.3 Published Estimating Data

Several companies routinely publish updated production rates and unit costs of resources for an extensive array of labor trades, materiel, and equipment for different countries and geographical locations within countries.

.4 Project Management Software

Project management software has the capability to help plan, organize, and manage resource pools and develop resource estimates. Depending upon the sophistication of the software, resource breakdown structures, resource availabilities, and resource rates can be defined, as well as various resource calendars.

.5 Bottom-up Estimating

When a schedule activity cannot be estimated with a reasonable degree of confidence, the work within the schedule activity is decomposed into more detail. The resource needs of each lower, more detailed piece of work are estimated, and these estimates are then aggregated into a total quantity for each of the schedule activity’s resources. Schedule activities may or may not have dependencies between them that can affect the application and use of resources. If there are dependencies, this pattern of resource usage is reflected in the estimated requirements of the schedule activity and is documented.

Section 6.3.3 Activity Resource Estimating: Outputs

The output of the Activity Resource Estimating process is an identification and description of the types and quantities of resources required for each schedule activity in a work package. These requirements can then be aggregated to determine the estimated resources for each work package. The amount of detail and the level of specificity of the resource requirement descriptions can vary by application area. The resource requirements documentation for each schedule activity can include the basis of estimate for each resource, as well as the assumptions that were made in determining which types of resources are applied, their availability, and what quantity are used. The Schedule Development process (Section 6.5) determines when the resources are needed.

.2 Activity Attributes (Updates)

The types and quantities of resources required for each schedule activity are incorporated into the activity attributes. If approved change requests (Section 4.6.3.1) result from the Activity Resource Estimating process, then the activity list (Section 6.2.3.2) and activity attributes (Section 6.2.3.3) are updated to include those approved changes.

.3 Resource Breakdown Structure

The resource breakdown structure (RBS) is a hierarchical structure of the identified resources by resource category and resource type.

.4 Resource Calendar (Updates)

A composite resource calendar for the project documents working days and nonworking days that determine those dates on which a specific resource, whether a person or materiel, can be active or is idle. The project resource calendar typically identifies resource-specific holidays and resource availability periods. The project resource calendar identifies the quantity of each resource available during each availability period.

.5 Requested Changes

The Activity Resource Estimating process can result in requested changes (Section 4.4.3.2) to add or delete planned schedule activities within the activity list. Requested changes are processed for review and disposition through the Integrated Change Control process (Section 4.6).