Respondent driven sampling (RDS) is a network sampling technique typically employed for hard-to-reach populations (e.g. drug users, men who have sex with men, people with HIV). Similar to snowball sampling, initial seed respondents recruit additional respondents from their network of friends....

Mit prozessproduzierten Daten des Forschungsdatenzentrums der Rentenversicherung (FDZ-RV) werden soziale Unterschiede beim Zugang in die Erwerbsminderungsrente (EM-Rente) untersucht, wobei auch die zugrunde liegenden und für die Rentenbewilligung maßgeblichen Krankheitsdiagnosen...

The current economic crisis requires fast information to predict economic behavior early, which is difficult at times of structural changes. This paper suggests an innovative new method of using data on internet activity for that purpose. It demonstrates strong correlations between keyword...

Technology has always introduced changes in the way researchers administer surveys. A new technology known as virtual worlds has now emerged that promises to change data collection once again. Virtual worlds are persistent, online, computer-rendered spaces populated by hundreds, thousands, or...