Abstract: The present invention relates to a system and method for efficiently estimating the sensitivity, or elasticity, of customer demand to changes in price in a business-to-business market environment. More particularly, this method relies on a parametric demand model, and a corresponding offer model which is referred to as the Joint Demand Model. This model is used to estimate the elasticity of market segments using win-only transactional data. In addition, this invention provides a method for efficiently calculating the estimation error of the estimated elasticity, and uses such estimation error in a weighting scheme based on a hierarchical model in order to produce a reliable estimate of elasticity.