To analyse all factors is difficult, because most of the factors influence each other. Following approaches can be used for the estimation: top-down estimation and bottom-up estimation. The top-down techniques are formula based and they are relative to the expenses for development:
Function Point Analysis (FPA) and
Test Point Analysis (TPA) amongst others. Bottom-up techniques are based on detailed information and involve often experts. The following techniques belong here:
Work Breakdown Structure (WBS) and
Wide Band Delphi (WBD). We can also use the following techniques for estimating the test effort: • Conversion of software size into person hours of effort directly using a conversion factor. For example, we assign 2 person hours of testing effort per one Function Point of software size or 4 person hours of testing effort per one use case point or 3 person hours of testing effort per one Software Size Unit • Conversion of software size into testing project size such as Test Points or Software Test Units using a conversion factor and then convert testing project size into effort • Compute testing project size using Test Points of Software Test Units. Methodology for deriving the testing project size in Test Points is not well documented. However, methodology for deriving Software Test Units is defined in a paper by Murali • We can also derive software testing project size and effort using Delphi Technique or Analogy Based Estimation technique. == Test efforts from literature==