Establish Estimates of Work Product and Task Attributes

Size is the primary input to many models used to estimate effort, cost, and schedule. The models may also be based on inputs such as connectivity, complexity, and structure. The estimates should be consistent with project requirements to determine the project’s effort, cost, and schedule. A relative level of difficulty or complexity should be assigned for each size attribute.

• Determine the technical approach for the project. The technical approach defines a top-level strategy for development of the products. It includes decisions on architectural features, such as distributed or client server; state-of-the-art or established technologies to be applied, such as robotics, composite materials, or artificial intelligence; and breadth of the functionality expected in the final products, such as safety, security, and ergonomics.
• Use appropriate methods to determine the attributes of the work products and tasks that will be used to estimate the resource requirements. Methods for determining size and complexity should be based on validated models or historical data. The methods for determining attributes evolve as our understanding of the relationship of product characteristics to attributes increases.
• Estimate the attributes of the work products and tasks.
• Estimate, as appropriate, the labor, machinery, materials, and methods that will be required by the project.