Thirty-two of Japan’s 47 prefectures, or 68 percent, are considering the introduction of Level 4 self-driving buses — vehicles fully automated under certain conditions — a Kyodo News survey showed, reflecting growing expectations for the new technology as a way to tackle the worsening driver shortage. The number rose to 36 prefectures when asked if they plan to experiment with or use less autonomous Level 2 buses, which allow human drivers to take their hands off the wheel and get assistance in braking and acceleration. Japan revised its road traffic law in last April, paving the way for Lev…