Datenerhebung bei Mietspiegeln: Überblick und Einordnung aus Sicht der Statistik

Der Artikel diskutiert die verschiedenen Methoden bei der Datenerhebung von Mietspiegeln. Es werden Vor- und Nachteile der in der Praxis zu findenden Methoden diskutiert und aus dem statistischen Blickwinkel beleuchtet. Dabei gehen wir den drei Fragen nach: Wer wird befragt? Wie wird befragt? Wie erfolgt die Stichprobenziehung? Neben statistischen Aspekten werden die Mietspiegel der 30 größten Städte als Beispiel herangezogen, um aufzuzeigen, dass die angewandte Methodik in der Praxis sehr heterogen ist

Immune suppression of vaccine-induced CD8+ T-cell responses by gamma retrovirus envelope is mediated by interleukin-10-producing CD4+ T cells

Retroviral envelope (Env) proteins have long been recognized to exhibit immunosuppressive properties, which affect the CD8+ T-cell response to an infection but also to immunization. Interestingly, we previously showed in the Friend murine leukemia virus (F-MuLV) model that the surface Env protein gp70 also plays a role in immunosuppression, in addition to the immunosuppressive function attributed to the transmembrane Env protein. We now demonstrate that immunization with F-MuLV Env leads to a significant increase in interleukin-10 (IL-10)-producing CD4+ T cells and that the induction of CD8+ T-cell responses in the presence of Env is rescued if the capacity of CD4+ T cells to produce IL-10 is abrogated, indicating a mechanistic role of IL-10-producing CD4+ T cells in mediating the Env-induced suppression of CD8+ T-cell responses in Env co-immunization. We found that CD8+ T-cell responses against different immunogens are not all equally affected. On the other hand, suppression of immunity was observed not only in co-immunization experiments but also for immune control of subcutaneous tumor growth after an Env immunization. Finally, we show that suppression of CD8+ T cells by the surface Env protein is observed not only for Friend MuLV Env but also for the Env proteins of other gamma retroviruses. Taken together, our results show that IL-10-producing CD4+ T cells mechanistically underlie the Env-mediated suppression of CD8+ T-cell responses and suggest the presence of an immunosuppressive motif in the surface Env protein of gamma retroviruses

Statistische Beratung

Windmann M. Statistische Beratung. QM - Quantitative Methoden in Forschung und Praxis. Vol 26. Hamburg: Dr. Kovac; 2010

Functional Hourly Forecasting of Water Temperature

Mestekemper T, Windmann M, Kauermann G. Functional Hourly Forecasting of Water Temperature. International Journal of Forecasting. 2010;26(4):684-699

Functional hourly forecasting of water temperature

The paper describes the problem of forecasting water temperatures on an hourly basis using previous water and air temperatures as predictors. Both time series are decomposed using functional principal components, leading to low dimensional vector autoregressive modeling. The principal component scores mirror serial correlation, which is also incorporated in the model. The modeling exercise is motivated by and demonstrated with data collected in the German river Wupper, and the approach is contrasted to alternative routines which have been suggested in statistics and hydrology.

Regulation of Water Temperature of River Wupper

Windmann M, Kauermann G, Hoffmann A, Tischbierek J, Leonhard V. Regulation of Water Temperature of River Wupper. WASSERWIRTSCHAFT. 2011;101(9):25-29.The introduction of a forecasting based temperature management in the river Wupper in Germany has significantly improved the general living conditions of the native fish population in downstream locations of two thermal power plants. This advancement is achieved by fixing ecologically justified upper thresholds for the water temperature and by implementing a statistical forecasting tool for the water temperature with consideration of the discharge of cooling water

Temperaturmanagement der Wupper im Bereich der Kraftwerke Barmen und Elberfeld

Windmann M, Kauermann G, Hoffmann A, Tischbierek J, Leonhard V. Regulation of Water Temperature of River Wupper. WASSERWIRTSCHAFT. 2011;101(9):25-29.The introduction of a forecasting based temperature management in the river Wupper in Germany has significantly improved the general living conditions of the native fish population in downstream locations of two thermal power plants. This advancement is achieved by fixing ecologically justified upper thresholds for the water temperature and by implementing a statistical forecasting tool for the water temperature with consideration of the discharge of cooling water