Kumar P

In this chapter you will learn about:

• The differences between sampling in qualitative and quantitative research • Definitions of sampling terminology
• The theoretical basis for sampling
• Factors affecting the inferences drawn from a samp le
• Different types of sampling including:
- Random/ probability sampling designs
- Non-random/ non-probability sampling designs
- The 'mixed' sampling design
• The calculation of sample size
• The concept of saturation point

Keywords: accidental sampling, cluster sampling, data saturation point, disproportionate sampling, equal and independent, estimate, information-rich, judgemental sampling, multi-stage cluster sampling, non-random sample, population mean, population parameters, quota sampling, random numbers, random sample, sample statistics, sampling, sampling design, sampling element, sampling error, sampling frame, sampling population, sampling unit, sample size, sampling strategy, saturation point, snowball sampling, study population, stratified sampling, systematic sampling.

RESEARCH METHODOLOGY

The differences between sampling in quantitative and qualitative research
The selection of a sample in quantitative and qualitative research is guided by two opposing philosophies. In quantitative research you attempt to select a sample in such a way that it is unbiased and represents the population from where it is selected. In qualitative research, number considerations may influence the selection of a sample such as: the ease in accessing the potential respondents; your judgement that the person has extensive knowledge about an episode, an event or a situation of interest to you; how typical the case is of a category of individuals or simply that it is totally different from the others. You make every effort to select either a case that is similar to the rest of the group or the one which is totally different. Such considerations arc not acceptable in quantitative research.
The purpose of sampling in quantitative