The Sizing Unit section is where you set the unit used to record project size on the project’s Assumptions page. Project size has two aspects:
•Function Unit. The function unit is a way of representing the size
of the developed software product (newly developed, modified, or reused
software). Examples are logical source statements, function points,
stories or story points, requirements, and web pages. If you need to add a
function unit to the list of available size units, contact your site
administrator and ask him or her to add the desired unit to the selection list.
If an uploaded Estimation project, template, or SLIM-DataManager
database contains function units with no counterpart in the Function Units
table, the “new” function unit will be added to the Function Units lookup
table. The Administrator will have the option to validate this function
unit and include it in drop-down lists available to other SLIM-Collaborate users
and projects.
•Gearing Factor. The gearing factor normalizes software measured in different sizing units to a common frame of reference: the base size unit. For example, a project with 50 function points at a gearing factor of 50 converts to 2500 (50 FP * 50 base size units per FP) base size units. One hundred objects at a gearing factor of 300 is equivalent to 30,000 base size units. The base size unit represents the smallest identifiable unit of programming work: it is roughly equivalent to the time and effort it takes to write one line of code. SLIM-Collaborate provides a default gearing factor for each of the function units but you can replace the default gearing factor with one from your history.
The project size is used during benchmarking and calculation of the PI or other productivity metrics (Size per phase 3 effort unit or phase 3 month). It is also used to position projects against similarly sized projects on relevant internal or industry trend lines.