Business formation — a network approach

This article suggests that the key to entrepreneurial success is to be found in the ability to develop and maintain a personal network. In elaborating this proposition I regard the environment of the business venture as “enacted”. The inexperienced new entrepreneur needs support to create a personal network and to manage the enacted environment. The concept of the “organizing context”, defined as a clustered sociocentric network, is introduced to provide a tool with which the entrepreneur can deal more efficiently with the different subprocesses that create his or her reality. The approach supplies a framework within which various forms of entrepreneurship — indigenous, corporate, etc. — can be compared and analysed beyond their institutional differences. The interaction between various forms of entrepreneurship and organizing contexts is empirically illustrated from case studies.     

Transforming the Energy System—the Evolution of the German Technological System for Solar Cells

To improve our understanding of processes involved in the formation and growth of new technological systems in the energy sector and to identify the associated key challenges for policy makers managing the transformation process, we examine the development of the German technological system for solar cells over the past 25 years. We use a "technological system' approach in which we will trace the evolution of actors, networks and institutions that have a bearing on the generation and diffusion of solar cells. An initial preparatory stage lasted until about 1989 and was mainly characterized by knowledge build-up induced by a Federal RDD programme. This was followed by a second stage characterized by political struggle over the regulatory framework and a subsequent beginning of a virtuous circle for solar cells. In the concluding discussion, we emphasize four key features of the evolution of the technological system: (1) the role of a coalition of system builders that successfully influenced the regulatory framework so that markets could be formed: (2) the considerable length of the learning period and the large number of actors that need to learn; (3) the importance of policies that form early markets (not only early niche markets, but beyond those) as only markets may induce firms to enter and learn, and (4) the need to run market formation policies simultaneous to policies that maintain technological variety.     

Forecasting nonstationary time series—Some methodological aspects

The Box-Jenkins approach to time series analysis, which is an efficient way of analyzing stationary time series, recommends differencing as a general method for transforming a nonstationary time series into a stationary one. This paper gives a methodological discussion of some other ways of transforming a nonstationary series, in particular removing linear trends. It is argued that in many cases removing trends is superior to differencing in several respects. For example, when the process generating the time series is an ARMA(p,q) process added to a linear trend, differencing will produce an ARMA(p,q + 1) process that violates the invertibility conditions and is therefore difficult to estimate. The discussion is extended to time series with seasonal patterns.