The addition of other factors to suit local circumstances is encouraged. With both the Albrecht and Symons methods. I Ps can be counted for previous projects where actual effort is know n. If you have figures for the effort expended on past projects (in work-days for instance) and also the system sizes in FPs, you should be able to work out a productivity rate, that is:
productivity = size! effort
For new projects, the function points can be counted and then the effort can be projected using the productivity rate derived above:
effort = size/productivity
A more sophisticated way of doing this would be by using the statistical technique, least squares regression, to derive an equation in the form:
effort = constantl + size x constant,
Symons is very much against the idea of using function points to estimate SLOC rather than effort. One finding by Symons is that productivity, that is. the effort per function point to implement a system, is influenced very much by the size of the project. In general, larger projects, up to a certain point, tend to be more productive because of economies of scale. However, beyond a certain size they tend to become less productive because of additional management overheads.
Some of the rules and weightings used in FP counting, especially in the case of the Albrecht flavour, are rather arbitrary and have been criticized by academic writers on this account. l:Ps. however, are w idely used in practice because of the lack of other methods of gauging the functional size of information systems.
See R. D. Banker. R. Kauflman and R. Kumar. An Empirical Test of Object-based Output Measurement Methods' Journal of MIS. 8(3). 1993.
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What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.