Linking article parts for the creation of newspaper digital library

An important issue pertaining to the retro-conversion of newspapers, i.e. the conversion of newspaper issues into digital resources, is the identification and appropriate digital representation of an article. To complete this task, a number of steps have to be followed, from segmentation of the newspaper image to optical character recognition and linking of different items belonging to the same article. In this paper, an evaluation of different information retrieval techniques is presented that aim at linking textual parts of an article that can be found on different pages of a newspaper issue. Three document matching techniques are evaluated, namely title-to-title, title-to-text and text-to-text matching. In addition, the effect on the matching accuracy of using a stemmer and of employing appropriate conflict resolution techniques is studied for each of the above approaches. Experimental results involving a number of issues of a Greek newspaper show that the best technique, namely text-to-text matching augmented with a stemmer and conflict resolution, can reach a high linking accuracy rate of 96%.