Variance Analysis is the only entry under the Tools and Techniques head of the Control Scope process. And it is an important tool for project scope management knowledge area.
As the name implies, Variance Analysis is where the Project Manager measures and compares two values. This can also result in change requests.
These two values are basically the planned baseline work and the actual work. Ideally, planned and actual project progress should give same values but we do not live in an ideal World.
Variance Analysis is done to figure out if the plan needs to be corrected. Corrective or preventive actions can be recommended which can then be put through the change control process to bring the project back on track
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