handset manufacturers in U.S.A, Europe, and Japan. We choose the "event study" methodology to evaluate the impact of iPhone … carriers and the handset manufactures in U.S.A, Europe and Japan?" The results show that the impacts of iPhone present … results of financial profits show that almost of all telecommunications carriers in U.S.A and Japan grow their profits after …

with the size of production units. These distortions lead to sharp reductions in plant productivity and the fraction of … are critical in accounting for the differences in size distribution between the U.S. and Japan. -- distortions ; size … ; skill investments ; productivity differences …