  Cost estimation is a very crucial field for software developing companies. In
the context of learning organizations, estimation applicability and accuracy
are not the only acceptance criteria. The contribution of an estimation
technique to the understanding and maturing of related organizational processes
(such as identification of cost and productivity factors, measurement, data
validation, model validation, model maintenance) has recently been gaining
increasing importance. Yet, most of the proposed cost modeling approaches
provide software engineers with hardly any assistance in supporting related
processes. Insufficient support is provided for validating created cost models
(including underlying data collection processes) or, if valid models are
obtained, for applying them to achieve an organization's objectives such as
improved productivity or reduced schedule. This paper presents an enhancement
of the CoBRA(R) cost modeling method by systematically including additional
quantitative methods into iterative analysis-feedback cycles. Applied at Oki
Electric Industry Co., Ltd., Japan, the CoBRA(R) method contributed to the
achievement of the following objectives, including: (1) maturation of existing
measurement processes, (2) increased expertise of Oki software project decision
makers regarding cost-related software processes, and, finally, (3) reduction
of initial estimation error from an initial 120% down to 14%.
