| since 2003 | Lecturer in Empirical Sociology, Department of Social Science, University of Duisburg-Essen |
| 2003 | Postdoctoral lectureship status (habilitation) in empirical sociology, University of Duisburg-Essen |
| 1987-1996 | Supervisor of the computer department, MPI for the Study of Societies, Cologne |
| since 1987 | Research Fellow, Max Planck Institute for the Study of Societies, Cologne |
| 1985-1986 | Visiting Fellow, Department of Sociology, Stanford University |
| 1984 | Doctorate in political science, University of Duisburg |
| 1981-1987 | Research Associate in the Department of Sociology, University of Duisburg |
| 1978-1980 | Research Fellow, German Research Foundation project "The Analysis of Social Networks," University of Duisburg |
| 1976-1978 | Psychologist for the educational service of the Westphalian Miners’ Union in Bochum |
| 1970-1976 | Studied psychology and social sciences, Ruhr-Universität Bochum; Diplom |