None — Most Americans do not even know what their blood type is, but people in Japan can rattle it off as quickly as they can tell you their address. Many in Japan believe that a person's blood type is an indicator of their personality. They look at it similarly to how some Americans view horoscopes. According to Melanie Shintaku, BellaOnline's Japanese Culture Editor, people with type A blood are thought to be organized, perfectionists and self restrained. Those with type A are the most artistic of the blood groups. They are most compatible with other type A's or AB's. Blood type B personalities are stereotypically easy going, strong minded and individualists. They are most compatible with people who also have type B blood or AB. People with AB blood are thought to have split personalities. They can be both outgoing and shy, and tend to be trustworthy. AB's are thought to be compatible with every blood type. O type personalities are outgoing and creative, but they don't always finish what they start. Type O's are compatible with other O's and AB's. In the United States, internet dating sites currently allow people to narrow down the selection by age, race, religion and even income. Perhaps one day blood type will become a desired standard.