1. A method for processing preference information in a computing system comprising at least one processor configured to process the preference information and a storage device configured to store at least some of the preference information, the method comprising: determining one or more acceptable changes, each acceptable change corresponding to an attribute of a comparison product; and determining a particular change in share of the comparison product in a case that the comparison product is changed according to one or more of the one or more acceptable changes, wherein determining the particular change in the share comprises: determining, for each of a plurality of respondents, a total utility of each product of interest and of the comparison product; determining, for each respondent, a most-preferred product of the products of interest and of the comparison product based on the total utilities thereof; determining a share of the comparison product based on a number of respondents for whom the comparison product is most-preferred; determining, for each of the plurality of respondents, a total utility of the comparison product as changed according to the one or more of the one or more acceptable changes; determining, for each respondent, a most-preferred product of the products of interest and of the changed comparison product based on the total utilities thereof; and determining a share of the changed comparison product based on a number of respondents for whom the changed comparison product is most-preferred; and determining attribute levels of each of the plurality of products of interest; wherein the determination of the particular change in share of the comparison product is based at least on the one or more of the one or more acceptable changes and on preference information associated with a plurality of respondents, wherein the steps of determining are performed using said processor.