Project Estimation is a consistent process of estimating a project through data analysis and refining to design a project estimate which represents an approximate calculation of quantity or worth of the project. It is the way to investigate whether a given project is worth of initiation and further planning by considering the key constraints, such as time, effort, cost and quality.
The process of estimating a project comes before the planning process. Its purpose is to prove that the project is effective and feasible in terms of the constraints. The process results in creating an estimate that includes the following components:
- Delivery Rate (person hours per deliverable)
- Project Effort (person hours)
- Duration (project time length)
- Speed of delivery (deliverables produced per elapsed calendar period)
There are many methods and techniques for estimating various projects. For example, Delphi method, Compartmentalization, History review, Structured planning, Event chain, Cocomo, others. All possible estimation methods and techniques can be classified by several groups, such as:
- Equations (using equations to calculate project constraints)
- Comparison (using a comparison analysis to review two or more projects and then define the best path of project implementation).
- Analogy (using historical and analytical data for estimating similar or parallel projects).