#
Fuzzy Theory

Some people may think fuzzy theory as the method to use human vagueness.

Fuzzy theory uses words as data, it seems to be vague.
But numerous range and function is defined to use words, so it is not vague.

##
If without fuzzy theory

If without fuzzy theory,
we define "long", "normal", "short" as

"long = over 5m", "short = under 1m".

This definition cannot be considered the difference of feeling of each people.

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Membership Function

Membership function is used to define the range of fuzziness.
Membership is defined by designer of the system.

By this function, for example,

"3m is long 0.5 + normal 0.5"

We can use vagueness of feeling.

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Role of Fuzzy Theory

I think the real role of fuzzy function is not "Theory to use vagueness mathematically",
but "Theory to change
quality data and quantity data
each other".

If quality data can be used as numerically,
human feeling can be analyzed by
Data Science
.

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