Statistical Views on Disasters with Reference to Marine Disaters near by Japan

Disasters have complicated causes and effects. Various parameters on disasters such as the ratio of the wounded to the dead (referred to as the W-to-D ratio), the mean time between accident (referred to as MTBA), the parametermof Weibull distribution give insight into the characteristics of various disasters.Recent statistics on marine disasters near by Japan are analyzed to find such parameters mentioned above. The result is compared with the similar analysis on other disasters on the street, railroad, air traffic, and also with similar analysis on fire hazards, typhoon damages and earthquakes. The MTBA of marine disasters are around 20 years per one accident and 200 years per one death. Both numbers are of the same order-of-magnitude as other means of traffic. However, the W-to-D ratio is nearly unity and next to the worst, which is the air accident. The Weibull parametermis of the same order-of-magnitude as other means of traffic, which is worse than fire hazards but better than earthquakes.