Abstract
Robertson's 2-poisson model to retrieve information does not use location information and category information. We constructed a framework using location information and category information in a 2-poisson model. We submitted two systems based on this framework at the IREX contest. Their precisions in the A-judgement measure were 0.4926 and 0.4827, the highest values among the 15 teams and 22 systems that participated in the IREX contest. This paper describes our systems and comparative experiments when various parameters are changed. These experiments confirmed the effectiveness of location information and category information.
