A parametric cost model is a group of cost estimating relationships used together to estimate entire cost proposals or significant portions thereof. These models are often computerized and may include many inter-related CERs (cost estimating relationships), both cost-to-cost and cost-to-non-cost. Some models use a very limited number of independently estimated values and a series of Parametric inter-related cost-to-cost and cost-to-non-cost estimating relationships to predict complex proposal cost structures..
…Parametric techniques focus on the cost drivers, not the miscellaneous details. The drivers are the controllable system design or planning characteristics and have a predominant effect on system cost. Parametrics uses the few important parameters that have the most significant cost impact on the product(s), hardware or software, being estimated. (NASA Parametric Cost Estimating Handbook)
