Regional innovation processes, regional innovation systems, RIS, regional knowledge networks, social network analysis, SNA, network structures. - Regionale Innovationsprozesse, regionale Innovationssysteme, regionale Wissensnetzwerke, soziale Netzwerkanalyse, Netzwerkstrukturen

We present a descriptive analysis of stylized facts for the German business cycle. We demonstrate that simple ad-hoc instructions for identifying univariate rules characterizing the German business cycle 1955-1994 lead to an error rate comparable to standard multivariate methods.

We derive conditions for decomposition and collapsibility of graphical interaction models for multivariate time series. These properties enable us to perform stepwise model selection under certain restrictions. For illustration, we apply the results to a multivariate time series describing the...