Authors: H. Eto 1 and K. Makino 2
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  • 1 The University of Tsukuba Institute of Socio-Technology 305 Sakura, Ibaraki (Japan) 305 Sakura, Ibaraki (Japan)
  • | 2 Chuo University Department of Mathematics Kasuga, Bunkyo-ku 112 Tokyo (Japan) Kasuga, Bunkyo-ku 112 Tokyo (Japan)
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Technological resources are shown to be more concentrated to a few firms than economic wealth. To explain such concentrations, the self-multiplication process with cycle between the innovative and stagnant ages is modeled in terms of the stochastic process. This yields a family of new distributions which is named the ultra-Yule distribution. This new distribution which is quite skew is show to fit the real distributions of patents and of R & D expenditure in the Japanese industry better than the Yule distribution. The properties of this new distribution is discussed.