Trends and volatility in Japanese patenting in the USA: An analysis of the electronics and transport industries

This paper analyses trends and volatility in patenting in USA by Japan in the electronics/electrical and motor vehicle/transport epuiqment industries. The number of patents has increased steadily, with the two industries accounting in 1997 for one-half of Japanese patents in USA. The electronics/electrical industry has been a much stronger performer, with a share of 30% of US patents, compared with 20% for motor vehicle/transport epuiqment. Using monthly data for 1975-1997, the time-varying nature of the volatility of patents registered in the USA is examined. The asymmetric AR(1)-GJR(1,1) model is found to be suitable for motor vehicle/transport epuiqment, whereas the AR(1)-GARCH(1,1,) and AR(1)-GJR(1,1) models provide interesting results for electronics/electrical