Читать книгу Handbook of Web Surveys - Jelke Bethlehem - Страница 41

A major problem of web‐based surveys is sample selection. For research applications, a random sample is desirable and often essential, and researchers may simply not have a comprehensive sampling frame of e‐mail addresses for people who drink fruit juices or go to church. Despite the huge growth of the Internet, there are still many people who do not have access to, or choose not to use, the Internet. There are also wide disparities in Internet access among ethnic, socioeconomic, and demographic groups. A sampling frame, including e‐mail addresses, of all members of the target population should be available to draw a random sample. In practice, this list is very rarely available. Therefore, large coverage problems arise, and this is the most relevant issue.

Sampling problems may particularly be an issue for general population surveys. For many specific populations, there are no problems. Examples are companies collecting customer satisfaction data, employers measuring job satisfaction, educators collecting course evaluations and conducting examinations, bloggers wanting to consult with their readers, and event organizers checking proposed attendance and meal and other preferences. While there is still a need for some caution, in terms of learning how to use the new technology with confidence, the use of web surveys has been growing rapidly and will clearly continue to grow. Inside the innovative contest web surveys present new methodological challenges, like the integration with other data sources.

A disappointing aspect of web surveys is that they do not contribute to solving the problem of decreasing response rates. It is widely recognized that they usually result in a rather low response rates. It should be noted that, despite low response rates, the use of server‐side and client‐side paradata can help to focus efforts on specific population that most need it.