A morphological, syntactic and semantic search engine for Hebrew texts

This article describes the construction of a morphological, syntactic and semantic analyzer to operate a high-grade search engine for Hebrew texts. A good search engine must be complete and accurate. In Hebrew or Arabic script most of the vowels are not written, many particles are attached to the word without space, a double consonant is written with one letter, and some letters signify both vowels and consonants. Thus, almost every string of characters may designate many words (the average in Hebrew is almost three words). As a consequence, deciphering a word necessitates reading the whole sentence. Our model is Fillmore's framework of an expression with a verb as its center. The engine eliminates readings of words unsuited to the syntax or the semantic structure of the sentence. In every verbal entry of our conceptual dictionary the features of the noun phrases (NP's) required by the verb are included. When all the correct readings of all the strings of characters in the sentence have been identified, the program chooses the proper occurrences of the searched word in the text. Approximately 95% of the results by our search engine match those in the query.