An information processing device comprising: an accident notification accepting unit configured to accept from a plurality of mobile objects an accident notification including site information indicating the site where impact greater than or equal to a threshold has occurred and a withdrawal notification for withdrawing said accident notification; an area identifying unit, and a transmitting unit, characterized in that the area identifying unit is configured to identify a withdrawal prone area based on the site information included in the accident notification withdrawn by accepting said withdrawal notification; the transmitting unit is configured to transmit information about said withdrawal prone area to said plurality of mobile objects, and said area identifying unit is configured to calculate the proportion of the number of accident notifications withdrawn by said withdrawal notifications to the number of accident notifications accepted by said notification accepting unit as a withdrawal rate for each area and to identify an area where said withdrawal rate is greater than or equal to a predetermined value as said withdrawal prone area, wherein said accident notification includes an information about an impact value of the impact, and wherein the information processing device comprises a threshold calculating unit configured to correct said threshold for each area based on information about impact values and the site information contained in not-withdrawn accident notifications, and wherein said transmitting unit is configured to transmit said corrected threshold to said plurality of mobile objects. an accident notification accepting unit configured to accept from a plurality of mobile objects an accident notification including site information indicating the site where impact greater than or equal to a threshold has occurred and a withdrawal notification for withdrawing said accident notification; an area identifying unit, and a transmitting unit, characterized in that the area identifying unit is configured to identify a withdrawal prone area based on the site information included in the accident notification withdrawn by accepting said withdrawal notification; the transmitting unit is configured to transmit information about said withdrawal prone area to said plurality of mobile objects, and said area identifying unit is configured to calculate the proportion of the number of accident notifications withdrawn by said withdrawal notifications to the number of accident notifications accepted by said notification accepting unit as a withdrawal rate for each area and to identify an area where said withdrawal rate is greater than or equal to a predetermined value as said withdrawal prone area, wherein said accident notification includes an information about an impact value of the impact, and wherein the information processing device comprises a threshold calculating unit configured to correct said threshold for each area based on information about impact values and the site information contained in not-withdrawn accident notifications, and wherein said transmitting unit is configured to transmit said corrected threshold to said plurality of mobile objects.