Development of a Stemmer for the Greek Language - SAIS

Of course there are suffixes which do not conflict and can easily be removed. For
example if we set a rule that removes the suffix “ΑΣ” for any given word, there is
no conflict with other words. This general rule covers a big amount on words in
the Greek language.
Finally, the rules, generic or specific, are applied each time for the longest
possible suffix in the list. So when we have the suffixes “Α” and “ΑΤΑ” in the
suffixes list, the word “ΚΥΜΑΤΑ” (waves) will be reduced on the stem “ΚΥΜ”
and not “ΚΥΜΑΤ”.
3.2 The rules
Trying to deal with each suffix individually, we have created a decentralized
algorithm. The different rules are presented below in pseudo-code:
Rule-set 1
if (word ends on Α∆ΕΣ|Α∆ΩΝ){
remove the suffix;
if (remaining part does not end on ΟΚ|ΜΑΜ|ΜΑΝ…){
add “Α∆”;
}
}
The rule removes the suffixes Α∆ΕΣ and Α∆ΩΝ for a group of words.
Example:
ΓΙΑΓΙΑ ΓΙΑΓΙ
ΓΙΑΓΙΑ∆ΩΝ ΓΙΑΓΙ
The rule doesn’t affect the group of words that by chance have similar suffixes.
Example:
ΟΜΑ∆Α ΟΜΑ∆
ΟΜΑ∆ΕΣ ΟΜΑ∆
Rule-set 2
if (word ends on Ε∆ΕΣ|Ε∆ΩΝ){
remove the suffix;
if (remaining part ends on ΟΠ|ΙΠ|ΕΜΠ…){
add “Ε∆”;
}
}
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