3 point estimation is most widely used technique and has to be only done experienced people. In this technique the project or task is divided into sub modules or sub tasks. For each task 3 possibilities would be considered. They are
a. worst case scenario.
b. best case scenario.
c. most likely scenario.
These can be defined depending on the experience of similar projects or past experience or historical data of the organization.
After arriving at the 3 values, the effort is calculated by averaging the worst case, best case and 4 times the most likely case.
The formula is
Effort = (best + 4 most likely + worst) / 6.
a. worst case scenario.
b. best case scenario.
c. most likely scenario.
These can be defined depending on the experience of similar projects or past experience or historical data of the organization.
After arriving at the 3 values, the effort is calculated by averaging the worst case, best case and 4 times the most likely case.
The formula is
Effort = (best + 4 most likely + worst) / 6.