The effects of software development environment on software cost estimation

This paper gives the results of our efforts to promote a software cost estimation model called (COnstructive COst MOdel) COCOMO. Our promotion was a suggestion to add a set of sixteen factors to the model. These factors are strongly related to Jordanian environment. To achieve this promotion, we have conducted many interviews with the consultant managers in some Jordanian software development organizations in order to find the factors that have an important impact on the environment. As a result of these interviews, a set of sixteen factors was derived. These factors are claimed to be the most influential factors in Jordan. In order to prove the claim, we have prepared and design a questionnaire. This questionnaire has been distributed to some leading software development organizations in Jordan. The analysis of the distributed questionnaire has supported the claim in selecting the most influential factors. The precise data for the analysis was collected from the record of 16 completed projects from sample of software development organizations in Jordan. We have applied the generic COCOMO II model to the 16 projects, and then we applied the suggested model (i.e. generic COCOMO II model together with the sixteen factors) to the same 16 dataset. A percentage error-test is used to see the degree of deviation between the actual and estimated effort. The suggested model produced good results comparing with generic COCOMO II model. These result,; give us good indication that the suggested model could be applied in Jordanian environment.