Estimation is defined by seven types based on the table below. GranTech can assist your company in developing proven techniques to estimate.
As the scope of a project increases, GranTech suggests multiple estimation methods to triangulate a precise estimate.
| Estimation approach | Category | Examples of support of implementation of estimation approach |
| Analogy-based estimation | Formal estimation model | ANGEL, Weighted Micro Function Points |
| WBS-based (bottom up) estimation | Expert estimation | Project management software, company specific activity templates |
| Parametric models | Formal estimation model | COCOMO, SLIM, SEER-SEM |
| Size-based estimation models | Formal estimation model | Function Point Analysis, Use Case Analysis, SSU (Software Size Unit), Story points-based estimation in Agile software development |
| Group estimation | Expert estimation | Planning Poker, Wideband Delphi |
| Mechanical combination | Combination-based estimation | Average of an analogy-based and a Work breakdown structure-based effort estimate |
| Judgmental combination | Combination-based estimation | Expert judgment based on estimates from a parametric model and group estimation |
