This article was originally published with incorrect affiliations for two authors.
The affiliation of Christoph Kern was originally given as Michigan Program in Survey and Data Science, University of Michigan, Ann Arbor, USA. The correct affiliation is University of Mannheim, Mannheim, Germany
The affiliation of Nicolas Rodriguez was originally given as Department of Statistics, University of Munich (LMU), Munich, Germany. The correct affiliation is Michigan Program in Survey and Data Science, University of Michigan, Ann Arbor, USA.
The errors have been corrected and the online HTML and PDF versions updated.
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