The philosophy of mixed methods research

THE PHILOSOPHY OF MIXED METHODS RESEARCH

This section covers the research philosophies that inform the mixed methods approach, specifically its epistemological and ontological underpinnings. As mixed methods is neither solely quantitative nor qualitative, the traditional (if contested) divisions between positivism and interpretivism and objectivism and constructivism are not especially useful in this setting. As such, the focus will be on pragmatism

(Tashakkori and Teddlie, 1998; Denscombe, 2002) as the most appropriate episte- mological approach and the notion of multiple realities (Onwuegbuzie et al., 2009) as constituting the ontological framework for mixed methods. The section ends by suggesting how pragmatism and multiple realities can be brought together under the mixed methods banner into a coherent overall approach.

Pragmatism

Epistemology is the branch of philosophy concerned with the theory of knowledge, and as such investigates our methods of acquiring knowledge, how we come to ‘know’ things and what justifications we have for considering something as ‘truth’ and accepting it as valid ‘knowledge’ within a particular discipline such as criminol- ogy (Bryman, 2016). In terms of truth, it would be useful to think about what is meant by ‘truth’ and how we know something to be ‘true’. For example, do you view the world as something that you can see and measure independently of your exist- ence in it? Or, is the world something that you can interact with and influence? Criminologists often define valid knowledge as evidence produced by rigorous and systematic research (although the exact nature of this can be contested and is deter- mined by one’s epistemology), rather than hearsay or ‘common sense’ knowledge which could be based on supposition or rumour. What you see as truth and valid knowledge will reflect your epistemological stance (your understanding of the world). Pragmatism tends to be the preferred epistemological standpoint of mixed methods research – what Denscombe (2014: 158) calls its ‘epistemological partner’. For the pragmatist, knowledge ‘is both constructed and based on the reality of the world we experience and live in’ (Onwuegbuzie et al., 2009: 122).

Pragmatism is not the only epistemology to be linked with mixed methods work.

Researchers have shown how mixed methods can be related to phenomenology (Mayoh and Onwuegbuzie, 2015), critical realism (Denscombe, 2014; Harrits, 2011; Layder, 1993, 1998; Lipscomb, 2008; Pawson and Tilley, 1997), constructivism (Denzin, 2012) or ‘transformative’ and ‘emancipatory’ epistemologies (Mertens, 2009; Onwuegbuzie and Frels, 2013). However, pragmatism is the most commonly adopted epistemology in such work.

One advantage of pragmatism is that it assists us in moving beyond the ‘paradigm wars’ (Bryman, 2016; Hammersley, 1992; Oakley, 1999) that pitch qualitative against quantitative and positivism against interpretivism. Instead, pragmatism encourages the researcher to take a more practical approach to their work, driven primarily by the needs of the research question at hand. So, whilst ‘the “theory” might say that positivism and interpretivism are incompatible in terms of their basic beliefs about social reality, in practice social researchers have tended to pick and choose from the array of methods at their disposal’ (Denscombe, 2002: 23). Pragmatism takes the philosophical stance that ‘good social research depends on […] what it is practical to accomplish and what kind of data are required’ (Denscombe,

2002: 24). For example, if you wanted to research female prisoners you could exam- ine official statistics from the Ministry of Justice (quantitative), but this would only provide a partial picture. You could also carry out interviews with female prisoners (qualitative), but this alone would give limited insight. With pragmatism, combining quantitative and qualitative data gives you a fuller picture and a greater depth of understanding. Furthermore, the practicalities associated with completing an under- graduate dissertation differ greatly to a multi-million pound international research project. For both of these, you might use mixed methods and take a pragmatic approach, but these projects would look quite different due to the scale, scope and means (time and money) of the research questions being investigated. An under- graduate dissertation studying female prisoners might contain a small-scale non-probability questionnaire of people’s perceptions of female prisoners, alongside a handful of interviews on the same topic. In contrast, a fully funded international research project could use Ministry of Justice statistics, as well as interviews with prisoners and prison officers, case studies and documentary analysis.

The guiding principle for pragmatists is not how well a piece of research adheres to ‘its “positivistic” or “interpretivistic” epistemology, but how well it addresses the topic it is investigating’ (Denscombe, 2002: 23). This is why pragmatism is so useful for mixed methods research: it puts the research question(s) at the heart of the research process and allows the researcher to move beyond the traditional qualitative/ quantitative divide. It focuses on utilizing the best research tools for the problem at hand and how to get the most from them. It recognizes the strengths and weaknesses of different strategies and seeks to combine them in such a way as to accentuate their positives and compensate for their negatives, all the while being driven by a desire to provide an answer to the research question(s). Pragmatists therefore ‘con- sider the research question to be more important than either the method they use or the worldview that is supposed to underlie the method’ (Tashakkori and Teddlie, 1998: 21).