1. A computer implemented method for determining an indicator correlative to a condition of an asset comprising the steps of: obtaining data correlative to operation of an asset wherein the obtained data is comprised of exemplar observations; creating membership functions directly from the obtained data by centering each of the membership functions on a different exemplar observation of the obtained data for obtaining the membership functions having membership function centers that are the exemplar observations and introducing an overlap parameter for controlling an extent by which the membership functions overlap each other; acquiring current asset data from the asset; and utilizing the membership functions and the current asset data for evaluating antecedents and consequents of conditionals for determining an indicator correlative to a condition of the asset.