PERT

• Program Evaluation and Review Technique (PERT)


  A project management tool used to plan, schedule, and control complex projects
• PERT


  • Developed in the 1950s by the U.S. Navy for the Polaris submarine missile program
  • Designed to facilitate the identification and management of the tasks necessary to complete a project
• Events and Milestones


  • Specific points in time that mark the start or completion of one or more activities.
  • In PERT, events are typically represented as nodes in a network diagram.
• Activities


  • Tasks that consume time and resources, represented by arrows in the network diagram.
  • Each activity has a preceding event and a succeeding event.
• Time Estimates in PERT

  • Optimistic Time (O): The minimum possible time to complete the activity, assuming everything proceeds better than is normally expected.
  • Most Likely Time (M): The best estimate of the time required to complete the activity, assuming everything proceeds as normal.
  • Pessimistic Time (P): The maximum possible time to complete the activity, assuming everything goes wrong (excluding major catastrophes).
• Network Diagram


  A visual representation of the project's activities and events, showing the sequence and interdependencies of tasks. This is often a directed graph where nodes represent events and arrows represent activities.
• Critical Path


  The longest path through the network, which determines the shortest possible duration for the project. Any delay in activities on the critical path will delay the entire project.
• Steps in PERT


  1. Define the Project and Its Key Tasks

  2. Sequence the Activities

  3. Estimate the Time for Each Activity

  4. Develop the Network Diagram

  5. Calculate the Critical Path

  6. Update the PERT Chart as the Project Progresses
• Earliest Start (ES) and Earliest Finish (EF)


  The earliest times an activity can start and finish without delaying the project.
• Latest Start (LS) and Latest Finish (LF)


  The latest times an activity can start and finish without delaying subsequent activities or the project.
• Slack or Float


  The amount of time an activity can be delayed without affecting the project completion date. Activities with zero slack are on the critical path.
• Improved Planning and Scheduling


  
  

  • Clear visual representation of the project’s activities and their dependencies
  • Helping managers to plan and schedule more effectively.
• Enhanced Decision-Making


  Facilitates better decision-making by identifying the critical path and potential bottlenecks.
• Flexibility


  • Can be applied to projects of any size and complexity
  • Making it a versatile tool in project management.
• Risk Management


  By incorporating time estimates with a range of scenarios, PERT allows managers to anticipate and plan for potential risks and uncertainties.
• Time-Consuming and Complex


  Large projects with many activities.
• Subjectivity in Time Estimates


  Over-focusing on it might lead to neglecting other significant activities that are not on the critical path but are still crucial to project success.
• Static Nature


  • PERT charts can become outdated quickly as projects evolve.
  • Requiring constant updates to remain relevant and accurate.