ABSTRACT
This chapter explores some of the typical procedural approaches for creating a project time and cost estimate, but be aware that estimating is an art form as much as a mechanical process or scientific formula. It reviews the general topic of estimating project time and cost. Parametric estimating uses a statistical relationship between historical data and other variables to calculate an estimate for activity parameters, such as cost, budget, and duration. From a mechanical perspective, the work unit estimating cost drivers are primarily linked to the associated labor work component, materials required, and other miscellaneous costs allocated to that work unit. The Delphi Technique is another variety of expert judgment estimating. It is mostly used when making high-level estimates in the early stages of projects where there are many unknowns, and a single expert would bring too much bias to the solution. Analogous estimating is best used in the early phases of a project before significant details are available.
