Key points are not available for this paper at this time.
Vicki G. Morwitz, David Schmittlein, Using Segmentation to Improve Sales Forecasts Based on Purchase Intent: Which "Intenders" Actually Buy?, Journal of Marketing Research, Vol. 29, No. 4 (Nov., 1992), pp. 391-405
Morwitz et al. (Sun,) studied this question.