Scoring function
A standardization procedure used to convert measured values or subjective ratings to unitless values usually between 0 and 1. This allows all soil property measurements to be integrated into one value or index for soil quality. The four general types of scoring functions used in soil quality assessments are: more is better (higher measurements mean higher soil quality, e.g. SOM); less is better (lower measurements mean higher soil quality, e.g. salinity); optimum range (a moderate range of values is desirable, e.g. pH); undesirable range (a specific range of values is undesirable)