Designing the sampling frame

Thus far in the research process, the research problem under investigation and the research objectives have been highlighted, the information types and sources have been identified, the research design has been determined and the steps undertaken in the preparation of the research design have been presented. Figure 5.6 illustrates the process that the researcher followed when drawing a sample of the population.

Figure 5.6: The sampling process

Adapted from: Iacobucci and Churchill (2010:283); Tustin et al. (2005:96)

Phase1

• Define the target population

Phase 2

• Specify the sampling frame

Phase 3

• Select the sampling method

Phase 4

• Determine the sample size

Phase 5

• Draw the sample

Phase 1: Define the target population

From Figure 5.6, it can be seen that the first phase in the sampling process is defining the target population. Iacobucci and Churchill (2010:282) define a target population as the entirety of cases that match some chosen requirements. Malhotra (2012:369) describes a target population as the collection of elements or objects that possess the information the researcher is seeking. Defining the target population, in other words, entails translating the research problem into a precise statement of who should and should not be included in the sample for the study (Malhotra, 2012:369).

According to Barbour (2007:59), it is essential that the members of the target population share at least one important characteristic. The target population in this study was defined as any person who had been exposed to a Springbok rugby match through any medium in the Tshwane region. The term ‘exposed’ in this context can be delineated to include the following:

• Individuals who have watched a Springbok match at any rugby stadium or on a television set;

• Individuals who have seen sponsor branding on the Springbok playing attire;

• Individuals who have seen sponsor messages on a television set or at any rugby stadium;

• Individuals who may have attended a Springbok match as a social activity and in the process were exposed to sponsor messages and branding.

Phase 2: Specify the sampling frame

The sampling frame is referred to as a list of the members of the population from which units to be sampled are to be selected (McDaniel & Gates, 2010a:330). In an ideal situation, a precise sampling frame would include a complete list of individuals who would participate in the study. However, this list is not always available. The sampling frame will therefore specify the procedure that will produce a representative sample with the desired characteristics (McDaniel & Gates, 2010a:331).

The study conducted by Repucom (2012) found that 20% of the South African population

92.8% of the population were interested in rugby and had access to a television through which they could be exposed to rugby. Since the study at hand was an exploratory study, using non-probability sampling, it was not necessary to draw up a sampling frame.

Exploratory research is conducted on a small and non-representative sample, so findings should be regarded as tentative and can be used as building blocks for further research (Malhotra, 2012:100).

Phase 3: Select the sampling method

The sampling methods available to the researcher can be divided into two types, namely probability sampling and non-probability sampling. In essence, probability sampling means that it is possible to answer research questions and to achieve objectives that require the researcher to estimate statistically the characteristics of the population from the sample (Saunders et al., 2009:213). However, in non-probability sampling, the probability of each case being selected from the total population is not known and it is impossible to answer research questions or address objectives that require statistical inferences about the population under investigation (Saunders et al., 2009:213). These sampling methods can further be divided into various categories which are illustrated in Figure 5.7. The discussion will now focus on these categories.

Figure 5.7: Types of sampling methods

Adapted from: Iacobucci and Churchill (2010:285); Saunders et al. (2009:213)

• Probability sampling

Probability sampling offers a number of advantages, as discussed by McDaniel and Gates (2010a:334). These include that the researcher can be sure of obtaining information from a representative cross-section of the population, sampling errors that may occur can be computed and the survey results can be generalised to the entire population. As can be seen from Figure 5.7, probability sampling comprises simple random sampling, stratified sampling, cluster sampling and systematic sampling.

• Simple random sampling: This is a sampling method in which units of the population are randomly selected individually and directly (Wiid & Diggines, 2013:192). Each unit is selected in such a manner that it has an equal probability of being selected for the sample.

• Stratified sampling: According to Wiid and Diggines (2013:195), stratification is a two-step process where the diverse population is firstly grouped into identical groups that

are mutually exclusive as well as comprehensive, and then a random sample of units is drawn independently from each group using either random or systematic sampling.

• Cluster sampling: This is much like stratified sampling where the first step is to divide the population into mutually exclusive and extensive groups which are referred to as clusters (Shukla, 2008:61). Nargundhar (2008:103) states that a cluster could be established on the basis of any criterion, but marketers could establish clusters in terms of geographical areas, membership to sports team supporter clubs or positions of influence held within a household.

• Systematic sampling: This is a flexible form of probability sampling (Cooper & Schindler 2011:378). In this approach, every n^th unit in the population is sampled. The selection begins with a random start of a unit in the range of 1 to n.

The above sampling methods each offer their unique advantages, but it is important to take note of their disadvantages. These probability sampling methods can take more time to implement and the relative magnitude of sampling errors is large (Malhotra, 2012:383).

The next sampling method that can be identified, as illustrated in Figure 5.7, is non-probability sampling.

• Non-probability sampling

Kapoor and Kulshrestha (2010:142) explain that in non-probability sampling, units in the population have an unequal or zero chance of being selected as a sample element. This therefore means that findings cannot be generalised beyond the sample. Non-probability sampling methods include:

• Convenience sampling: Units or participants are obtained according to how conveniently available they are (Zikmund & Babin, 2010b:423).

• Quota sampling: This involves precise characteristics that the units must possess. The aim of this sampling method is to produce a sample that reflects a population in terms of the relative proportions of people in different categories such as gender, cultural groups, age and geographic locations (Zikmund & Babin, 2010b:425).

• Snowball sampling: A form of judgement sampling that is appropriate to use when a small and specialised population is targeted (Aaker et al., 2011:350). The researcher purposefully chooses a number of units with the qualities that are particularly essential

and these units are then used to further identify other units that encompass the same qualities (Wiid & Diggines, 2013:190).

• Judgement sampling: The researcher selects the sample based on their judgement about some appropriate qualities needed from a member of the sample population (Zikmund & Babin, 2010b:424).

For the purpose of this study, a non-probability sampling method was employed. This method was deemed suitable because the aim of the study was to explore the effects of sponsorship on the consumers’ decision to purchase the sponsors’ product. Due to the exploratory nature of the study, the main aim was not to make statistical inferences and therefore it was not necessary to have a representative sample (Malhotra, 2012:100). It is for this reason that a non-probability sampling method was suitable as the researcher could rely on her own judgement as to who should be included in the target population (Zikmund & Babin, 2010b:424). Another reason for the use of non-probability sampling is that costs are lowered and procedures required to develop a sampling frame are eliminated (Aaker et al., 2011:349). As much as non-probability sampling was suitable for the study, it is not without fault. A major disadvantage of non-probability sampling that should be noted is that the accuracy with which the consequential information can be presented is uncertain (Aaker et al., 2011:349). In addition, results in this study may contain hidden biases and uncertainties. The research findings of the study also cannot be generalised to the entire population.

The non-probability sampling method that was employed in this study is snowball sampling. This method was used as it enabled the researcher to handpick the target population. The researcher relied on her own judgement to select initial individuals who conformed to the predetermined qualities (the individuals in the population must have been exposed to a Springbok match). The remainder of the population was identified from the initial individuals selected. The inclusion criteria were the following:

• Males and females who were 18 years or older;

• Any person who had been exposed to a Springbok rugby match (discussed more in the section that follows);

• Any person who resided in the Tshwane area within Gauteng;

• Any individual who was able to understand, read, write and speak English.

Although individuals younger than 18 years old were eligible to participate in the study, only individuals who were 18 years or older were included in the study as the study received ethical clearance from the university to have direct involvement only with persons over the age of 18.

The next phase in the sampling process is determining the sample size chosen for the proposed study.

Phase 4: Determine the sample size

A sample size can be defined as the number of participants that ought to be integrated in the research to ensure that the results are representative of the entire population, provided that the purpose of the study is to do so (Kolb, 2008:187). According to Wiid and Diggines (2013: 200), the researcher is therefore required to select a sample that is sufficiently large to yield a moderately specific estimation of the population values but that can simultaneously be executed economically and practically. Kolb (2008:188) has identified a number of factors that researchers should consider when determining the sample size:

• The more variation there is within the population, the larger the population will need to be

For example, suppose a sponsor of the Springboks is considering introducing a new cellular phone to the market. They would need to know the technological preferences of consumers who are technologically savvy, those who may not be technologically savvy, those who can afford the latest technological gadgets and those who may not be able to afford them.

• The thoroughness in the exhaustiveness between the given answer by the participant and the reality of the population as a whole

For example, a question posed to respondents might ask them how much they would be willing to pay for a particular new cellular phone with added features. In this case the researcher would need to establish the range or interval amount that they are willing to accept when considering the true characteristic of the population in its entirety.

• The need for assurance that the research conclusions truly reveal authentic data about the population

Complete accuracy would entail a census study to be conducted. Since this is not always possible, the researcher must decide what level of confidence is needed to determine whether there is sufficient statistical power to indicate whether a result such as a relationship between two variables is statistically significant. This can be remedied by means of a larger sample. In the case of the study at hand, data was collected until saturation was reached. This means that focus groups were conducted with consumers until no new information was obtained from the participants.

Two focus group sessions were held with six participants in each group. The participants were asked to complete naïve sketches prior to the focus group sessions. The total of the naïve sketches used in the analysis was twelve and the transcriptions from the focus group interviews were also used. Since the study at hand was an exploratory study with the sole purpose of merely exploring the purchase decisions of consumers, two focus groups were deemed acceptable when the point of data saturation was reached (Sage Encyclopedia, 2008:3). In Chapter 4, various types of sports consumers were identified, which include players, patriots, appreciators, socialites, friends and voyeurs (see section 4.2.2). Each type of consumer would have a different reaction to sponsorship as each consumer’s consumption of a sporting service is motivated by varying factors. It is therefore essential that individuals within these consumer segments be included in the sample size in order to obtain data that explores the purchase decisions of consumers within the target population. In order to achieve this diversification, participants were asked to categorise themselves in the naïve sketches according to the consumer segments identified in Chapter 4.

The last phase in the sampling process as illustrated in Figure 5.6 is to draw the sample.

Phase 5: Draw the sample

According to Wiid and Diggines (2013:204), this phase in the sampling process involves selecting the participants from which data will be collected. For the purpose of this study, the specific sample unit was identified and selected as per the inclusion criteria. The initial sample unit was specific as the aim was to identify individuals with specific characteristics.

have known who could participate in the study (also referred to as snowball non-probability sampling). The participants were then invited by means of an email to participate in the study. The topic and aim of the study, the date as well as the time of the focus group were communicated to the participants.

The discussion thus far has led to the sixth step in the research process, designing the research instrument, as indicated in Figure 5.2.