Defining scope of query for location-dependent information services

The demand of information services has fueled in recent years. However, the requested of correct answer in a mobile environment needs to have more attentions. This is due to the scope of query depends to the user location. In this paper, we propose an algorithm by using a square as a query scope. The aim is to increase chances to find rare targets. We assume that the client is at the corner boundary of the square when it receives the answer. Our results show that using a square is more efficient in finding the target if the target is rare instead of using other shapes, especially circle.