Topic map based indexing and searching apparatus

A topic map based searching apparatus, comprising:

• a question pre-processing block to, by a computer, normalize a user question in a single form, correct grammatical errors and remove insignificant symbols, to thereby provide a pre-processed user question;
• a question analysis block to, by a computer, analyze the pre-processed user question to acquire question analysis information;
• a similar question search block to, by a computer,
• limit a search space to a specific topic node of a pre-stored community question/answer (Q/A) topic map depending on the question analysis information, the Q/A topic map having stored therein index information containing pre-processed community Q/A lists for plural different community sites on web, respectively, and Q/A analysis information acquired by analyzing the pre-processed community Q/A lists,
• search similar questions from community Q/A lists belonging to the limited search space, and
• rank the searched similar questions depending on the question analysis information;
• and
• an answer extraction block to, by a computer, remove redundant answers among answers to the ranked similar questions, rank the answers, and extract a highest ranking answer as a best answer,
• wherein the question pre-processing block includes:
• a one unit recognizing unit to normalize, in a single form, allomorph words or words recognizable as one unit with respect to the user question by referring to a unit dictionary database;
• and
• an error pre-processing unit to correct the grammatical errors in the user question and remove the insignificant symbols from the user question by referring to a pre-processing rule database.