Organizational characteristics explaining participation in sustainable business models in the sharing economy: Evidence from the fashion industry using conjoint analysis

Environmental and social challenges require new sustainable business models, like sharing platforms. However, sharing platforms differ widely in their contribution to a more sustainable society. Whereas idealistic sharing platforms have dominant social goals, other sharing platforms are, or became, commercial. We explore the attractiveness of the typical organizational characteristics of idealistic sharing platforms in the fashion industry context, an industry with negative environmental and social impacts. Based on a literature review and exploratory focus groups, we conduct an online survey using conjoint analysis, completed by 1,512 respondents. Our results reveal that potential users prefer clothes sharing platforms to be small, to not partner with large clothing retailers, to have the possibility to participate in decision‐making, but to not require shareholding.     

Regression analysis on serial dilution data from virus validation robustness studies

To ensure the safety of plasma-derived medicinal products, the Dutch Blood Supply Foundation (Sanquin) performs virus validation experiments. Data from these experiments are based on serial dilution assays. Regression analysis on assay data faces several problems: only a small number of data points are available, data contain censoring and are subject to sampling error. Furthermore, the process variability inherent to the experiments is not evident. In this paper we address these problems by introducing a regression model for serial dilution data and by analyzing how validation experiments and simulation techniques can help elucidate various sources of variability the experiments are subject to. These are then incorporated into the regression model.     

Preisdeterminanten des Stromgroßhandels in Frankreich

This article provides a model-based analysis of the French spot market for electricity. Therefore a cost optimizing dispatch model is applied in order to derive a broader understanding of the liberalized electricity market in France considering empirical spot market prices in 2009. At first analysis of market structure and power plant mix is done in accordance with the european framework. The state of supply side competition is suggested as well. Due to the high portion of nuclear energy in the French energy mix the technical availability forecast of the plants plays a crucial role during the price formation on the wholesale market. As a result prices determined by the model are highly correlated with the French spot market. The results suggest a functioning pricing mechanism although deviations occur by ex-ante uncertain demand or unscheduled non-usability of generating units.     

Purchasing power parity as an approximation to the equilibrium exchange ratio

Purchasing power parity (PPP) is re-examined in models with trade impediments and intermediate products that are not traded. A distinction is made between ‘local consumption PPP’ and ‘total consumption PPP’. These are tested on several data sets, with largely negative results.     

Fair ranking of teachers

Economic theory suggests that it is optimal to reward teachers depending on the relative performance of their students. We develop an econometric approach, based on stochastic frontier analysis, to construct a fair ranking that accounts for the socio-economic background of students and schools and the imprecision inherent in achievement data. Using German PIRLS (IGLU) data, we exploit the hierarchical structure of the data to estimate the efficiency of each teacher. A parsimonious set of control variables suffices to get a “fair” estimate of unobserved teacher quality. A Hausman–Taylor type estimator is the preferred estimator because teacher efficiency and some exogenous variables may be correlated.