PERT (Program Evaluation and Review Technique) is a project management method used to plan, schedule, and control uncertain projects. Unlike CPM, PERT considers uncertainty in activity times using probability.
쮽킹 Key Idea of PERT
Each activity has three time estimates:
- Optimistic time (to) ᔒ shortest possible time
- Most likely time ™ ᔒ normal time
- Pessimistic time (tp) ᔒ longest possible time
쮽킹 Expected Time Formula
te=to+4tm+tp6t_e = \frac{t_o + 4t_m + t_p}{6}
쮽킹 Variance of Activity
σ2=(tpᖒto6)2\sigma^2 = \left(\frac{t_p – t_o}{6}\right)^2
쮽킹 Steps in PERT
- List all activities
- Identify dependencies
- Estimate to,tm,tpt_o, t_m, t_p
- Calculate expected time tet_e
- Draw network diagram
- Find critical path (like CPM)
- Compute project duration and variance
Exercise Files