ABSTRACT
This chapter focuses on Internet surveys as part of a mixed-mode design. In survey research there are two basic forms of data collection, self-administered questionnaires and standardized interviews, and these are mainly characterized by the absence or presence of an interviewer. Interviews can be performed face-to-face or over the telephone, and self-administered questionnaires can be handed over by an interviewer during an interview or sent by paper mail or through the Internet. The goal of mixed-mode surveys is to combine data from different sources into one data matrix for analysis. The fact that respondents to different modes may have different background characteristics and therefore provide different answers is an advantage of mixed-mode surveys. The importance of the medium of administration for data quality has long been recognized in diagnosing and assessment. Self-administered questionnaires have been found again and again to lead to less social desirability bias and more openness in answering sensitive questions when compared to interview surveys.
