ABSTRACT
Polls based on a good questionnaire and simple random sampling makes it possible to compute valid estimates of population characteristics. The poll will produce valid and reliable results that can be generalized to the target population. There are always practical problems that affect the outcomes of polls. One of the most important problems is nonresponse. Nonresponse occurs when people in the selected sample do not provide the requested information, or when the provided information is unusable. This chapter presents some more background about the nonresponse problem. It focuses on the possible effects of nonresponse. The chapter expresses that it is important to take a look at nonresponse in polls. It contains a simple introduction to weighting adjustment techniques. The three main causes of nonresponse are noncontact, refusal, and not-able. Nonresponse is a serious problem. To assess the quality of a poll, one must always take a look at the nonresponse situation.
