Chapter 17 key terms

A-0-A activity-on-arrow - a network diagram convention in which arrows designate activities.

A-0-N activity-on-node- a network diagram convention in which nodes designate activities.

Activities - steps in the project that consume resources and/or time.

Arrow indicates the direction of flow in the precedence diagram.

Beta distribution- in PERT with three time estimates for completion of an activity, the distribution form governing the calculation of the means and variances of activity completion times.

CPM (Critical Path Method) - PERT and CPM were developed separately at about the same time in the late 1950s. Both techniques are concerned with integrating and managing a project consisting of a number of different tasks.

Crash - to shorten an activity.

Crash time- the completion-time estimate for an activity resulting from crashing it.

Critical activity- an activity on the critical path.

Critical path- the path in a network diagram that takes the longest time for completion.

Deterministic- time estimate a single time estimate for an activity, with no alternative estimates or probability distribution of estimates.

Event- the starting and finishing of activities, designated by nodes in the AOA convention.

Gantt chart- visual aid used for scheduling simple projects.

Independence- the assumption that activity duration times are not related to each other and that each activity is on only one path.

Most likely time- the most probable length of time that will be required.

Network- (precedence) diagram - diagram of project activities that shows sequential relationships by the use of arrows and nodes.

Optimistic time- the length of time required under optimal conditions; the shortest time.

Path- a sequence of activities that leads from the starting node to the finishing node.

PERT- (Program Evaluation and Review Technique) see CPM.

Pessimistic time- the length of time required under the worst conditions; the longest time.

Predecessor - for two activities joined at a node, the predecessor is the one that precedes, and the successor is the one that follows.

Probabilistic -time estimates estimates of times that allow for variation.

Project - unique, one time operations designed to a specific set of objectives in a limited time frame.

Project champion - people within the company who promote and support the project.

Project life cycle- the definition, planning, execution, and termination of the project.

Risks - the danger of occurrences that can have undesirable consequences, such as delays or increased costs.

Slack - the allowable slippage for any activity; it is the difference between the length of a given path and the length of the critical path.

Work breakdown structure- a hierarchical listing of what must be done during a project.