Earthquake disaster risk map in east Java, Indonesia, using analytical hierarchy process — Natural break classification

East Java Province is one of potential disasters area in Indonesia such as earthquakes, tsunamis, landslides, floods, droughts, hurricanes, fires, terror and volcanic eruptions that was recorded in the study of disaster risks. East Java with an area of 47,799.75 km² and high population about 39,107,095 inhabitants, the government must make decisions quickly in disaster emergency system and good mitigation planning to reduce disaster victims. One of the frequent disasters in East Java is an earthquake, that can not be avoided and cause many casualties. In this paper, we build a system to calculate the risk of earthquakes in the districts of East Java. There are three criterias to determine the risk level of the earthquake, that consist of threats, vulnerabilities and capacities. Index method calculate the disaster risk value based on a threshold nominal value of the certain range, even though some of the criterias involve preference values. The proposed systems is developed using the analytical hierarchy process (AHP) based on those criteria that can solve the combination of nominal and preference values of criterias. AHP produce priority value and then it classify the earthquake disaster risk into three level of low, medium and high using natural break classification method. The system generate disaster risk map to visualize the level of earthquake risk.