A philosophical basis for mixed methods research

In human geography, a “divisive gulf” has traditionally been perceived between the quantitative and qualitative research traditions (Philip, 1998: 261) with this division

underpinned by the ‘incompatibility thesis’, which posits that these diverse research positions preclude one another (see Howe, 1988 for a discussion). As indicated in Table 3.5, each ‘paradigm’ is thought to be associated with specific ontological and epistemological

foundations and therefore incongruent with the other (McEvoy and Richards, 2006). The use of mixed methods has nevertheless become widespread in social science and, in recent years, writers in both geography and cognate disciplines, such as sociology and psychology, have advocated a move beyond this “myopic dualism” (Philip, 1998:273; Sui and DeLyser, 2011; Barnes, 2009; Goetz, Vowles and Tierney, 2009; Teddlie and Tashakkori, 2009; Bryman, 2006). Nevertheless, some, such as Sale, Lohfield and Brazil (2002:44), claim that mixed methods have been “adopted uncritically” and their validity has thus been called into question by suggestions that their use has expanded without resolution of debate surrounding conflicting philosophical underpinnings. This highlights the importance of making the philosophical basis for the use of mixed methods explicit in any study taking this approach.

Table 3.5: Traditional distinctions drawn between the qualitative and quantitative ‘paradigms’

(adapted from McEvoy and Richards 2006:68; Sale et al, 2002)

Quantitative paradigm Qualitative paradigm Ontology Tangible reality Intangible reality

Epistemology Positivism - Regularities established via empirical research and

deductive/inductive reasoning

Interpretivism - Knowledge constructed via social interaction/hermeneutic understanding

Methodology Hypothesis testing In depth fieldwork

Data analysis Verification/falsification Interpretation of meaning

The primary philosophical approach drawn on in the quest to look beyond the quantitative- qualitative divide has been pragmatism (Johnson, Onwuegbuzie, and Turner, 2007; Johnson and Onwuegbuzie, 2004) and a summary of the key rationales for and critiques of its use as a basis for mixed methods research are provided below. Evidently, however, this philosophical tradition has a long history and features marked diversity. A more complete summary of this epistemology and its evolution is given in Smith (2009). Nevertheless, for some, mixed

56 to form a key part of this (Denscombe, 2008:280). Termed ‘compatibilist’ by some, in the context of mixed methods research, pragmatists have advocated the choice of research methods on the basis of the research problem being addressed (Johnson et al., 2007; McEvoy and Richards, 2006) and this approach has gained popularity by emphasising the

commonalities between the quantitative and qualitative research traditions (Greene and Caracelli, 1997; Johnson and Onwuegbuzie, 2004; Johnson et al. 2007).

However, in spite of its popularity, critics have argued that the epistemological and ontological issues related to mixed methods (highlighted in Table 3.5) are marginalised rather than

resolved by this philosophical standing (Bryman, 2007; McEvoy and Richards, 2006; Sale et al., 2002; Philip, 1998). In some instances, it has been termed an “anti-philosophy” (Johnson and Onwuegbuzie, 2004:18) and pragmatists have been accused of ‘paradigm switching’ by authors who question their academic credibility (Howe, 1988; Bryman, 2006). While pragmatists themselves may see this switching as an important benefit of their approach, allowing an emphasis on practicality, it has enabled opponents to argue that mixing methods on this basis “often diminishes the value of both methods” (Sale et al., 2002:50). As Elwood (2010:100) notes, the pragmatist approach “enables us to do mixed methods” but there appears to be a need to consider an alternative philosophical basis for mixed methods research which views philosophy as a more integral part of research.

The call for increased variety in the philosophical foundation for mixed methods research (Johnson et al. 2007) provides an impetus to search for a middle ground between the aforementioned epistemological ‘incompatibility thesis’ and the ‘compatibilist’ disregard of these concerns, considered by some (such as Sale et al., 2002) to form part of the pragmatist approach. However, for this to occur a “fluidity and multiplicity in relating epistemology and methodology” (Elwood, 2010:97) is required. Epistemology has traditionally been conflated with research method in a dictatorial manner implying that those who follow a particular research philosophy must accordingly use certain methods, and that those who use particular methods must adhere to a certain worldview (Sale et al,. 2002). However, in the context of mixed methods research, it is more useful to not conflate philosophy and method,

acknowledging that while epistemology influences research methods, specific techniques are not determined by it (Bryman, 2008; Johnson and Onwuegbuzie, 2004; Greene and Caracelli, 1997). Most mixed methods researchers highlight that, in actuality, the division between quantitative and qualitative methods is in many ways artificial. Bryman (2006) has noted, for

57 example, that qualitative data can derive from a quantitative method and vice versa and geographers, such as Philip (1998), have highlighted that the focus on the difference between qualitative and quantitative methods has obscured the commonalities between them. What becomes important is finding an epistemological stance which incorporates a view of the world and gathering of knowledge that enables quantitative and qualitative data be related and be considered equally valid.

Drawing on an anti-conflationist stance, this thesis engages with a critical realist perspective as the foundation for a mixed methods approach. McEvoy and Richards (2006:69) suggest that critical realism offers a “more principled” philosophical basis for mixed methods than pragmatism, by enabling the researcher to view both quantitative and qualitative data as useful and analyse them without the need for the ‘paradigm switching’. This relatively new research philosophy emerged in the 1970s with the writings of Roy Bhaskar, whose works, A Realist Theory of Science (1975) and The Possibility of Naturalism (1979),are considered cornerstones of its foundation (Baert, 2005). Since its inception, critical realism has increased in popularity, offering a way to view social research as scientific whilst simultaneously offering a critique of existing positivist and interpretivist approaches (Baert, 2005). Situating itself on the middle ground it draws on aspects from both established approaches, working to overcome what it sees at their key flaws. It may therefore prove particularly useful in well- established disciplines such as human geography as is it not entirely dismissive of established approaches (Baert, 2005). Evidently, however, as with any epistemological stance, there is diversity within the critical realist approach (Danermark, Ekström, Jakobsen and Karlsson, 2002) which may have been exacerbated, to some extent, by its application to both natural and social sciences. Different aspects are adhered to more or less stringently by different authors (for instance, contrast Sayer (1992), Yeung (1997) and Bhaskar (1975)). The key aspects of the approach, engaged with in this thesis are outlined below (for a more extended introduction see Baert (2005) or for a more detailed discussion of critical realism in social science see Danermark et al. (2002)).

As indicated by its name, critical realism adopts a realist ontological foundation, advocating that a real world does exist external to people’s perceptions of it. Together with this it is suggested that researchers can in principle access this reality. A notion of human fallibility is, however, encompassed as it is acknowledged that social scientists can be mistaken within this. This is where this perspective differs notably from postivism which suggests that “the

58 scientist’s conceptualisation of reality actually directly reflects that reality” (Bryman, 2008:14). The incorporation of human fallibility is enabled by the “stratified notion of reality” that is the foundation of the critical realist approach (Baert, 2005:92).This view of reality differentiates between the level of the actual (observable events), the empirical (people’s perceptions of these events) and the real (underlying structures and generative mechanisms for these events). It is this stratified reality that appears to open the door most readily to a mixed methods approach as quantitative methods can be employed to glean data on observable events while qualitative methods can be utilised to access people’s perceptions of these at the empirical level. This view of reality also forms a middle ground between structure and agency and allows for the idea that the mechanisms generating events may not be, and often are not, observable.

Retroduction, the critical realist view of causation, engages with the search for these unseen mechanisms, its logic examining causal processes rather than looking for commonalities between different variables. As McEvoy and Richards (2006:71) emphasise it “involves moving from the level of observations and lived experience to postulate about the underlying

structures and mechanisms that account for the phenomena involved”. This form of reasoning appears very worthwhile as it leaves space for inconsistencies between what happens, what people think about events and the causes of these events. The attention to generative mechanisms in this thesis allows for the consideration of contexts, narratives and societal norms that may influence how people use and experience their local green spaces and shape the importance of locality and greenery in the lives of individuals. These two aspects, use and perception, taken together can be framed theoretically within the notion of value.

While this study retains a broad affinity with a critical realist approach, this is not to say that I see no problems with this stance. It has been highlighted by authors, such as McEvoy and Richards (2006,) that from a critical realist perspective the most valid account is the one with the most explanatory power. However, while I can accept the potential benefits of

retroductive reasoning and the notion of searching for causal processes or mechanisms, I struggle to see how the decision can be made than one account contains greater explanatory power than another. In this work, any explanation is considered to contain greater

explanatory power where it accounts theoretically for more of the data in the course of analytical generalisation. This work engages more readily the second key aim of critical realism, identified in the literature, which is to gain a more complete understanding of the

59 world. In looking to do this, it has been highlighted that some have struggled to put the critical realist perspective into practice (Baert, 2005) and, where this has been achieved, it has been more common for critical realists to utilise solely qualitative methods due to their potential flexibility (Baert, 2005). However, writers in critical realism have highlighted the benefits of quantitative knowledge, allowing for the development of a mixed methods research design (McEvoy and Richards, 2006). The design of this study is explored in the section the follows.