In this work we study the relation between investment in R&D, the technological innovation, diffusion, fluctuations and growth of output. Technological innovation is the result of a process (investment in R&D) whose final outcome is fundamentally uncertain. We model innovation as a Polya urn...

In the following Part II the deterministic and stochastic laws of motion arising from the processes depicted in Part I (particulary Section 2), are analyzed in detail. In section 4 we study the typical non-linear logistic model emerging as the deterministic equivalent of the diffusion processes...

We propose a hypothesis testing procedure to investigate whether the same growth rate distribution is shared by all the firms in a balanced panel or, more generally, whether they share the same functional form for this distribution, without necessarily sharing the same parameters. We apply the...

Empirical study of firms' growth and fluctuation requires the understanding of the dynamics of labor and productivity among firms by using large-scale data including that of small and medium-sized enterprises (SMEs). Specifically, the key to such understanding is the findings in statistical...