关键词: 本体, 林业领域, 文档特征, 权重模型, 语义相似度

Abstract: In the traditional feature weight of documents calculating, the model only considers the key word but other more relative words, so that the results of information retrieval are not comprehensive and precise. Aiming to solve these disadvantages above, this paper presents a model that calculates feature weight of document of forestry domain based on ontology. The steps of this model are as follows: calculate the feature weight using TF-IDF model; require the semantic distance, contact ratio and level difference between the key word and other relative words of document based on ontology, and then calculate the semantic similarity; calculate the feature weight using both results of TF-IDF and semantic similarity. The experiment proves that this improved model can increase the precision and recall ratio in documents retrieval, and meets the needs of users satisfactorily.

Key words: ontology, forestry domain, document feature, ranking model, semantic similarity