Computational Intelligence

282 Chapter Seven—Fuzzy Systems Concepts and Paradigms

occasionally, seldom, and never. Likelihood terms include certain, likely, possible,

uncertain, unlikely, and certainly not.

Linguistic Hedges

An important aspect of linguistic variables is that they can modify or qualify one

another. Consider, for instance, the word “very.” A “very tall” man is taller, in gen-

eral, than a “tall” one. In other words, “ver y” modifies tall by shifting it up on the

scale of height. But look w hat it does to “short”: A very short man is shorter than a

short man, so “very” shifts short down on the scale of height. Linguistic variables that

change the shape or position ...