Sampling in Research

Abstract

Research is aimed at the discovery and interpretation of facts, revision of accepted theories or laws in the light of new facts or practical application of such new or revised theories or laws. A sample provides needed information about the population quickly. However, there is no guarantee that any sample will be precisely representative of the population from which it comes. It is cheaper to observe a part rather than the whole. This chapter is a discussion on sampling in research and it is mainly designed to equip researchers with knowledge of the general issues to consider when sampling. The purpose of sampling in research, dangers of sampling and how to minimize them, types of sampling and guides for deciding the sample size are discussed. For a clear flow of ideas, a few definitions of the terms used are given. They highlight the types and methods of sampling, sampling errors and discusses techniques of sample size determination. Different types of sampling technique, how to carry them out, and their advantages and disadvantages are also introduced.

Homeowner perceptions and responses to buffelgrass invasion risk in the Tucson, Arizona Wildland-Urban Interface

“…Information gathered from the website of the City of Tucson indicated that there are a total of 146 HOAs in the city, out of which 38 of them were chosen for this study based on their location within the city's WUI, as well as the consent of their leadership to participate in the study. Respondents were recruited using self-selection sampling, a sampling technique that is used when the researcher wants members of a population of interest to choose to participate in the study on their own accord ( Mujere 2006 ). The researchers identified the contact information of the representatives of all HOAs within the Tucson WUI by visiting the websites of each organization and these representatives were contacted to solicit the involvement of their members in the study.…”

An Assessment of Climate Change Response Strategies In The Water Sector In Mutirikwi Sub-Catchment, Masvingo, Zimbabwe

“…A mixed-methods research design was adopted. According to Johnson and Onwuegbuzie [37], this model generally uses separate quantitative and qualitative where the strength of one adds to the strength of the other. Figure 2 below shows the procedure followed using the mixed methods approach.…”

“…The purposive and convenience sampling methods were used to select the participants. As purported by Modal [39] and Mujere [37] purposive sampling is sometimes known as judgmental, selective or subjective sampling. Occasionally known as grab or opportunity sampling is a non-probability sampling method that involves the sample being drawn from that part of the population that is close to the researcher.…”

“…Expert sampling was done where the researcher looked for individuals who have particular expertise in water resources management. Mujere [37] puts it that expert sampling is a keystone of a research design and is known as expert elicitation. This implies that the participants were tied to the objectives.…”

“…200 questionnaires were distributed, with 100 representing rural areas. The purposive and convenience method was chosen because it saves costs and time and allows fast data collection while the integrity and quality of data is maintained, Mujere [37].…”