Identifying and Selecting the Data

Figure 9 – Selecting Sources of Evidence

A. The Ice Cream Report, 1979

The use of secondary archival documents in the form of full market regulatory investigations was considered to be the most appropriate source of evidence given the research objectives. The investigation is called Ice-cream and Water Ices: A Report on the Supply in the United Kingdom of Ice-cream and Water Ices and was published in 1979 by the Monopolies and Mergers Commission. The report is in the public domain and narrates the findings of a full market inquiry conducted by the Commission into the market practices of the subsidiaries and associated companies of Unilever (including T Wall and Sons (Ice Cream Ltd), Wall’s) and those of J. Lyons & Company (JLC, including Glacier Foods Ltd and Lyons Maid Ltd) as national ice cream manufacturers, and of companies classed as secondary manufacturers. This is the first in a series of four investigations into the ice cream market by the Commission.

Vella and Foxall (2011) utilised the evidence from the final investigation, Competition Commission (2000), as the basis for their research⁸¹.

Case studies are especially susceptible to two important threats: (a) finding out in later stages of the research that the selected cases were

inappropriate or irrelevant to addressing the research objectives and, therefore, not viable (Vella and Foxall 2011; Yin 2014); and, (b) the cases did not contain the main variables of theoretical interest (Bryman and Bell 2007; Vella and Foxall 2011). There was sufficient familiarity with the case material to establish

81 It should also be noted that since the research did not make use of primary data involving human participation (e.g., focus groups, surveys, workplace observation and so on), Cardiff University does not require the need to gain ethical approval. Besides, the data is within the public domain and relates to events that occurred several decades ago. In addition, the Commission omitted any information that might have been confidential or commercially sensitive at the time.

early in the process whether the dataset had potential to accomplish the research goals (Eisenhardt 1989). Despite this familiarity, however, a number of similar reports were also screened according to a set of selection criteria to judge whether other more appropriate material was available (Vella and Foxall 2011; Yin 2014)⁸².

The ice cream report is the most appropriate to the research objectives for several reasons: (1) Familiarity with the Competition Commission (2000) investigation was believed to facilitate a quicker and deeper understanding of the dynamics in the ice cream industry and to enhance theory development by continuing along one path where earlier research left off. (2) The investigation is bound by a consistent theme and provides an extremely rich and detailed historical narrative of real world business activity (Vella and Foxall 2011) including the marketing practices of key rival manufacturing firms within their channels combined with detailed descriptions of patterns of wholesale and retail behaviours, and consumer choice. Thus, the report tracks continuity of

behaviour and the dynamics of change within the ice-cream industry in a

relatively comprehensive way. (3) The evidence in the report was compiled and analysed by several experts rather than a single researcher. (4) The report was generated and compiled by an unrelated third party and for purposes different to those that govern this research. Therefore, the case study is populated by evidence that has not been biased in any way by the researcher’s own

theoretical perspectives, expectations, assumptions, and otherwise. (5) The evidence contains highly specialised information that is generally not within the public domain or accessible to a single researcher (Vella and Foxall 2011). (6) The evidence appeared to hold features that are similar to the theories and perspectives under consideration (Rose 1991; Vella and Foxall 2011).

B. Single versus Multiple Sources of Evidence

The general prescription for conducting qualitative research is to use multiple sources of evidence and methods, i.e., triangulation (Eisenhardt 1989;

82 Appendix A2.3 provides an overview of the various possible sources of evidence screened as candidates for populating the research. Section A2.3.1 details the selection criteria used.

These criteria were based on theoretical considerations.

Pettigrew 1990; Miles and Huberman 1994; Patton 2002; Bryman and Bell 2007; Creswell 2009; Yin 2009; Miles et al. 2013; Yin 2014; cf. Mason 2002)⁸³.

The most significant benefits that are derived from multiple sources of evidence lie in (a) drawing upon the particular and varied strengths of the different instruments of data collection (e.g. Pettigrew 1990), (b) developing

“converging lines of inquiry” (Yin 2014, p. 122) or “cross-checks” (Pettigrew 1990, p. 277), (c) corroborating and enhancing the data collected (e.g.

Pettigrew 1990; Yin 2014), and, (d) construct validity (Yin 2014)⁸⁴. Essentially, a corroborative strategy strengthens confidence in one’s findings and enhances the accuracy of conclusions (Yin 2014). Conflicting or inconsistent evidence, on the other hand, aid in identifying issues regarding the integrity of the data

sources, data collection instruments and the evidence itself (Miles et al. 2013).

This research relies entirely on the extent of triangulation used by the Commission (Vella and Foxall 2011). The investigation demonstrates a strong emphasis on triangulating from a variety of sources⁸⁵.

C. Limitations of the Evidence

There are several limitations arising from the use of secondary archival qualitative data and of a single source of evidence threatening the validity and reliability of the research.

The Commission’s investigation was produced for different research objectives and audiences (Stewart and Kamins 1993; Yin 2009; Vella and

83 For example, a single study may use a mix of interviews, archival evidence, documents, and direct observations. Even when using a single source of data, say interviews, some

researchers collect their data from multiple informants from any single site.

84 Mason (2002), on the other hand, is reluctant to place great importance on triangulation of method to establish validity: she correctly points out that triangulation of methods and sources imply a single and objective social reality that may be known through using different methods and sources of data (Yin (2014) seems aware of this assumption). And, therefore, cautions researchers to pay very close attention to the consistency between method and

ontological/epistemological assumptions. Mason (2002) suggests that explaining how researchers arrive at the conclusion of validity is more recommendable than using a wider variety of methods and sources of data. At best, methods triangulation captures the multi-dimensional aspects of the social world.

85 Section A5.8.2 in Appendix 5 details the sources of evidence used by the Commission to conclude its inquiry. Section A5.6.4 in Appendix 5 details the problems faced by the

Commission in generating certain quantitative data for estimating market size and share and the describes how it used a variety of sources to produce the estimates required at law.

Foxall 2011; Yin 2014) and from the value lens of a regulator (Vella and Foxall 2011, 2013). The evidence presented in the report is comprised of information collected from several third parties on a set of observable events. The evidence may not narrate the unfolding of events literally and objectively (Mason 2002;

Yin 2009; Vella and Foxall 2011; Yin 2014) and may be deliberately edited (Yin 2009, 2014). The report was constructed through the input of several officials and the authors may have not necessarily been the same persons who

conducted the actual investigations. Therefore, authors may have inadvertently or deliberately introduced their own biases, errors, subjective assessments, and interpretations of the original investigators. In addition, they may have missed some of the insights investigators may have developed during fieldwork. The latter may have also introduced similar biases, errors, and subjectivity in data instrument design and data gathering (Vella and Foxall 2011)⁸⁶. In addition, the report may contain biased, erroneous, and subjective opinions of the industry players themselves. Data unimportant to the investigation but critical to the present research may have been omitted. The Commission is the sole

‘narrator’ of events and, although there is significant evidence to demonstrate a fair degree of impartiality, the threat of being inadvertently influenced by the insights generated and conclusions drawn by the authors and the investigators remains possible.

Despite the initial screening of alternative reports and the iterative strategy, there remains a distinct possibility of an incomplete picture emerging (Vella and Foxall 2011). Certain theoretical propositions may not be examined because there is a lack of sufficient data. Also, relying on a single source of evidence might lead to wrong conclusions. However, given the overall quality and integrity of the data (including the extensive level of triangulation used by the Commission), the extensive historical coverage of events within the report, and the empirical quandary originally motivating the research, the option of populating the research with primary evidence was rejected (Vella and Foxall

86 For example, (Miles and Huberman 1994, p. 35) point out that in conducting open ended or semi-structured interviews, the interviewer may summarize the verbal reports of third party already at source or in the process of transcription. In this sense all interviews are open to this element of subjectivity; however, single source research is highly susceptible to the errors that arise from the particular source of data (Patton 2002, p. 556).

2011)⁸⁷. A strategy that involves actively and continually searching for evidence that may counter such insights and conclusions is followed during the analysis and interpretation (Miles et al. 2013; Yin 2014). Further, an awareness of all biases and retaining a critical perspective on the data reduces the threat of being misled by the evidence (Yin 2009; Vella and Foxall 2011; Miles et al.

2013; Yin 2014).