Phase 2 Retail and Distribution Audit

Theoretical sampling. The participant observation was conducted in the downstream section of the automotive aftermarket. The retail stores, DIY stores, super stores, distributors, car dealers, independent garages, motor factors and shops in petrol stations in the Bedfordshire area, in England, UK, provided the population interest, each representing a high management

position at each site. The area, being a fairly industrial/auto-related area, provided a good location for data collection for representativeness of concepts for this study. In order to identify and locate the relevant sites to choose for the participant observation, theoretical sampling was employed.

As mentioned in section 4.2.1, this study was designed in accordance with the grounded theory approach, which seemed to be particularly suitable to capture complex and problematic nature of motor oil branding. The data collection was conducted through the participant observations on a sample of marketing managers purposely selected according to the theoretical sampling criteria (Glaser, 1978; Strauss and Corbin, 2008). In accordance with the grounded theory criteria, theoretical sampling implies selecting participants on the basis of the developing analysis and the developed theory emerging from the data is successively modified from data attained from the next participant. In this study, rather than establish samples prior to data collection, the theoretical samples were responsive to the concepts derived from data allowing flexible and open sampling (Glaser and Strauss, 1967; Strauss and Corbin, 2008).

Sample size. In total, and with the concept driven nature of theoretical sampling, 57 companies in the UK (eight motor factors, twelve service stations, twelve independent garages, thirteen dealers, four DIY, three super stores, five middlemen) and 61 companies in Nigeria (eleven independent garages, thirteen service station, seven independent retail, twenty one dealers, nine middlemen) provided the sample size for this study. Consequently, this number of sites in the two countries allowed reaching data saturation (Strauss and Corbin, 2008).

Table 4.8: Table of different locations for the participant observations

Locations UK Nigeria

Service stations 12 13

Dealers 13 21

Independent garages 12 11

Middlemen 5 9

Motor factors 8 -

Super stores 3 -

DIY stores 4 -

Independent retailers - 7

Total sample 57 61

The choice to sample the different players in the automotive supply chain (manufacturers, suppliers, retailers and garages) was due to the fact that the members of the supply chain encompasses the companies involved with manufacturing, assembling and selling from the manufacture to the customer. The role of brand managers and developers are complementary in defining brand performance across the supply chain. Thus, their views, experiences and expectations related to motor oil were explored in order to develop a comprehensive understanding of motor oil branding phenomena. The variety of sites (see Table 4.8) allowed sampling a multiplicity of experiences that were significant and prototypical of the industries, to develop a deeper understanding of the branding phenomenon. Consistent with the UK study, theoretical sampling provided a guide to the Nigerian data collection. Furthermore, a checklist was designed by the researcher serving as units of analysis to serve as a preliminary guide.

In order to gain further insight the study used semi-structured interviews with seven Nigerian motor oil brand managers. This sample of brand manager’s accounted for 35% of the total population interest of the Nigerian brands. These respondents were ‘information rich’, in that they provided valuable information about branding in their companies. Table 4.9 shows the different interview sites. Additionally, as mentioned in Section 4.4.2, with a lack of interviewing brand managers in the UK, advertising copies allowed for gaining further insight. Table 4.10 shows the number of advertising copies obtained from Autocar, a weekly

Table 4.9: Different interview sites

Company Location Number

Total Nigeria PLC Abuja 1

Conoil Lagos 1

Oando Kaduna 1

Mubeco Petroleum Company Ltd

Kaduna 1

AZ Petroleum Products Kano 1

Lubcon Abuja 1

Castrol Lagos 1

Table 4.10: Number of advertising copies

Magazine Brands Number of copies

Autocar Castrol (EDGE, Magnate, GTX),

Mobil 1, Petronas

52

Rather than conventional qualitative sampling where the entire data is collected prior to analysis, theoretical sampling provides opportunities to sample concepts, which leads to more data collection, analysis, concept development and more questions until saturation is reached.

Researchers purposefully look for indicators of the concepts to allow examining the data to discover how the concepts vary in different settings (Strauss and Corbin, 2008). Figure 4.1 shows an example of the circular process of multiple comparisons of the theoretical sampling.

Among its advantages, it enables the discovery of concepts relevant to the set problems, therefore allowing exploring the concepts in depth. As it allows for discovery, it is important in studying new or unexplored areas to help strengthen the rigor of the study. Also, as new concepts emerge from the data, sampling becomes more specific allowing the use of unexpected events that may arise (Strauss and Corbin, 2008). Furthermore, theoretical sampling provides structure to collection and analysis of data.

Figure 4.1: Theoretical sampling process

Despite these various advantages, theoretical sampling indeed has some limitations. Due to its highly systematic process, the application of theoretical sampling requires more time and money compared to other qualitative sampling techniques. Also, its systematic process makes it more difficult to understand than the other sampling. More often, early researchers may mistake theoretical sampling to purposive sampling. However, unlike purposive sampling, it attempts to discover categories and their elements so that interrelationships between them can be detected and explained. Due to its focus on specificity, theoretical sampling does not allow a general understanding of the phenomena, but rather specific areas of the research interest.

Furthermore, as making theoretical sensitive judgement on saturation is not defined, knowing when to stop collecting data becomes difficult for early researchers (Seale, 2004).