Analogous estimating

Analogous estimation is an estimation method based on information from historical data from previous projects for similar tasks or deliverables. The more historical information the organization has, the easier it is to find a comparable tasks/deliverables. Historical data should be adjusted to the current task/deliverable to reflect differences in complexity, team members, etc. It provides a Rough Order of Magnitude (ROM).

Application

This type of estimation is often the first estimation done on a project, it can well be the only one done. It can be used in any industry. The accuracy level depends on the degree of similarity between the project to be estimated and the analogous project/deliverable the was estimated before.

Visual Representation, Example

You have a new project involving training on a subject for which previously have done similar training.

The previous project was training a single group for one day and preparation was 40 hours, plus 8 hours of class time.

Your new project comprises three groups and needs adjustment, for example, more and different examples.

To apply analogous estimation, you could estimate that adjustment and preparation will require 16 hours, plus 3 times 8 hours class time.

Other Estimating Techniques

• Three-Point Estimation
• Parametric Estimation
• Bottom-Up Estimation