Tokkyo seido no henkō wa kakaku kyōsō o kanwashi kigyō no kenkyū kaihatsu o unagashita no ka? 1998-nen kara 2013-nen no seido henkō ga jidōsha mēkā ni ataeta eikyō = Did modifications of the Japanese patent system lead to a reduction in price competition and the promotion of R&D activities? : the impacts of some modifications between 1998 and 2013 on the Japanese automobile industry