Project Manager case manual Study Series [9, 10] -- mandatory resource progress plan, application pert preparation progress plan

If the project manager cannot solve the resource allocation problem, the project progress plan will not succeed.

When most of the activities in a project are similar to other activities that have previously been executed, the Key Path Method (CPM) is usually used for planning. The estimation of the CPM activity duration is usually based on the duration data and uses the average value of the previous project activity duration.

The estimation of the basic assumptions of the PERT system is uncertain, so we talk about the range of the Activity Duration and the probability of the Activity Duration in this range, rather than assuming that the activity will be completed within a fixed period of time.

Terminology in the preparation of the PERT schedule:

PERT computing:

In order to combine these three solid ends and calculate the expected average duration of the activity, the PERT developer derives a formula based on the copper continuation principle.

T = (a + 4 m + B)/6

Estimate the probability of completion of a plan:

Expression for estimating standard deviations:

S = (B-a)/6

Once the Key Path of the network is determined, the standard deviation of the entire key path can be obtained by calculating the square root of the active variance and of the Key Path.

According to statistics, the probability of project completion is 68% within the plus or minus one standard deviation, 95% within the two standard deviations, and 99.74% within the three standard deviations.