The rating values are presented in the ‘‘XY” form to represent the tendency of
sub-feature ‘‘Y” to main feature ‘‘X”, such that more precise descriptions can be used to represent the relationships between the elements and the constructs. In this enhanced model,Xis the main tendency degree of the features;Y¼Xþi1 r represents the tendency degree of the
ith sub-feature, whereris the number of sub-features in that main tendency degree. For example, in the first row of Table 1, the main tendency degree of ‘‘Very long and thin” is 1, and the tendency degrees of the sub-features ‘‘Acicular”, ‘‘Linear”, and ‘‘Lance-shaped” are 1+(1–1)/3 = 1.0, 1+(2–1)/3 = 1.3 and 1+(3–1)/3 = 1.7, respectively.