Nonresponse in surveys may result in a distortion of the distribution of interest. In a panel survey the participation behavior in later waves is different from the participation behavior at the start. With register data that cover also the information for non-respondents one can observe a fade...

We propose a novel view of selection bias in longitudinal surveys. Such bias may arise from initial nonresponse in a probability sample, or it may be caused by self-selection in an internet survey. A contraction theorem from mathematical demography is used to show that an initial bias can...

Flexibles Carsharing bietet in den Städten eine Alternative zum privaten PKW-Besitz. Der mögliche Beitrag dieser Dienstleistungen zu einer Reduktion der Autoanzahl wird aber immer wieder kontrovers diskutiert. Die empirische Datenbasis zu dieser Frage ist bisher noch relativ klein. Die...

A large literature studies subjective beliefs about economic facts using unincentivized survey questions. We devise randomized experiments in a representative online survey to investigate whether incentivizing belief accuracy affects stated beliefs about average earnings by professional degree...

A general concern with the representativeness of online surveys is that they exclude the "offline" population that does not use the internet. We run a large-scale opinion survey with (1) onliners in web mode, (2) offliners in face-to-face mode, and (3) onliners in face-to-face mode. We find...

This report describes the design, data, and main results of an online survey (i.e., the "Judging Without Knowing" survey) that was conducted between October 2017 and June 2018 with more than 2,000 registered members on Clickworker (a commercial survey company in Germany). The survey was...