Changes in quality in information technology products provoke that compilation of their price indexes represent a major challenge. In this respect, the aims of this study are three. First, to build price indexes for personal computers during 1990-2004. Second, to compare our price indexes with...

Information on the number of interviewer contacts allows insights into how people's responses to questions on happiness are connected to the difficulty of reaching potential participants. Using the paradata of the German Socio-Economic Panel Study (SOEP), this paper continues such research by...

Our aim is to quantify the GDP measurement bias derive from quality improvements in information technology sector. Using hedonic price indexes for IT goods, our results show that between 2000 and 2004 economic growth rate was, at most, approximately 2% on average per year -and not 1.60% as is...

Differential item functioning (DIF) can lead to an unfair advantage or disadvantage for certain subgroups in educational and psychological testing. Therefore, a variety of statistical methods has been suggested for detecting DIF in the Rasch model. Most of these methods are designed for the...

Mixtures of item response theory models have been proposed as a technique to explore response patterns in test data related to cognitive strategies, instructional sensitivity, and differential item functioning (DIF). Estimation proves challenging due to difficulties in identification and...

Research on subjective wellbeing typically assumes that responses to survey questions are comparable across respondents and across time. However, if this assumption is violated, standard methods in empirical research may mislead. I address this concern with three contributions. First, I give a...

Nur wenige Studien geben Aufschluss über den Gesundheitszustand der in Deutschland lebenden Migrantenbevölkerung und beschränken sich meist auf rein medizinische Kriterien. Die vorliegende Arbeit vergleicht auf Grundlage von Daten des Sozio-oekonomischen Panels (SOEP) den Gesundheitszustand...