This article describes a method – called here “the method of Stretching Alongthe Paths” (SAP) – to prove the existence of chaotic sets in discrete-time dy-namical systems. The method of SAP, although mathematically rigorous, isbased on some elementary geometrical considerations and is relatively easy toapply to models arising in applications. The paper provides a description...

The paper considers random economic systems generating nonlinear time series on the positive half-ray R+. Using Lyapunov techniques, new conditions for existence, uniqueness and stability of stationary equilibria are obtained. The conditions generalize earlier results from the mathematical literature, and extend to models outside the scope of existing economic methodology. Applications to growt...

The paper discusses results of comparative surveys from years 2009-2011 which aimed at determining how the recent economic crisis influenced informatization strategies in Polish companies and institutions. The obtained results supported a working hypothesis that the economic crisis affected – to smaller or greater extent – shortand long-term informatization strategies in majority of companies o...