Document Expansion Method for Digital Resource Objects

Digital Resource Objects (DROs) suffer from shortage of its contents, and this leads to reduction in the effectiveness in its retrieval results. In order to increase the retrieval effectiveness of DRO, adding extra information to its contents is required. However, the extra information must be related to the structure of DRO. Each document contains metadata units with multiple topics. Document expansion (DE) methods utilize the unstructured documents to increase the document contents. In the same way, in this paper, an Enhanced Document Expansion (EDE) method is proposed by utilizing structured documents. DE method is a way of feeding and providing documents with new information to increase the effectiveness of the documents. Usually, traditional DE methods add terms to the original documents. In the proposed EDE method, a new procedure to increase the information content according to specific steps is added and aimed at adding new information which is more relevant and closer to each metadata unit in each document. The proposed EDE method calculates the nearest sentences to the content of the metadata unit by improving the probability estimation equation. The experiments which are conducted on cultural heritage CHiC2013 collections show a statistically significant improvement over the traditional document expansion methods.