What are the Criteria for a PhD?
PhD students often worry about whether their research will be good enough for a PhD. It's useful to remember the criteria which most universities have at the core of their PhD assessment: 'original work' which makes 'a significant contribution to knowledge'. It is no coincidence that most refereed journals and conferences use similar criteria - such publications are notionally how the research community communicates and continues to build knowledge. Therefore, you can provide evidence of 'significance', 'originality' and 'contribution to knowledge' in advance of submission of your thesis by publishing your work in refereed journals or conferences. There is more on this at various places later in this book. You don't need to make a major discovery to get a PhD - you just need to show that you're able to do good enough research independently.
Key dissertation ingredients
A number of ingredients are essential for a satisfactory dissertation:
- A thesis: one coherent over-riding 'story' or argument that embodies a research insight
- Situation in existing knowledge: a critical review of prior research which motivates and justifies the research question
- Contribution of something new (the 'significant contribution to knowledge')
- Appropriate voice and argument: the provision of clear and explicit evidence, substantiation and chain of inference
More hangs on the student's ability to demonstrate intellectual maturity and critical depth - and through them to provide insight - than on the scale or scope of the research findings. A good PhD is based on an honest report of research that reflects sound practice and well articulated critical thinking.
What is a 'significant' contribution?
Most students, when they hear the phrase ‘significant contribution’, think in terms of a new theory, crucial experiments, technological breakthroughs- the stuff of Nobel Prizes. For a PhD, the truth is that 'significant' need not mean 'revolutionary' or 'major' or even 'large'. The phrase might be more accurately read as 'significant - albeit modest - contribution'.
Characterizing your contribution means answering 'So what?', which means articulating:
- The importance of the question (Why is it worth asking?)
- The significance of the findings (Why should anyone care? Why do they matter?)
- Their implications for theory
- The limitations to generalization
Making a 'significant contribution' means 'adding to knowledge' or 'contributing to the discourse' - that is, providing evidence to substantiate a conclusion that's worth making. Research is not something done in isolation; it is a discourse among many researchers, each providing evidence and argument that contributes to knowledge and understanding, each critiquing the available evidence. Research is about the articulation and analysis of phenomena observed and investigated through a variety of techniques. It's about 'making sense' of the world: not just describing it, but also analysing and explaining it. As more evidence is presented, the analysis and explanations are re-evaluated. Knowledge claims can be small and still have a role in the discourse.
What sorts of contribution are typically made in dissertations?
- Re-contextualization of an existing technique, theory or model (applying a technique in a new context, testing a theory in a new setting, showing the applicability of a model to a new situation): showing it works - or that it doesn't - and why
- Corroboration and elaboration of an existing model (e.g. evaluating the effects of a change of condition; experimental assessment of one aspect of a model)
- Falsification or contradiction of an existing model, or part of one
- Drawing together two or more existing ideas and showing that the combination reveals something new and useful
- Demonstration of a concept: showing that something is feasible and has utility (or showing that something is infeasible and explaining why it fails)
- Implementation of theoretical principle: showing how it can be applied in practice; making concrete someone else's idea, and hence showing how it works in practice and what its limitations are
- Codification of the 'obvious': providing evidence about what 'everyone knows' (possibly providing evidence that received wisdom is incorrect)
- Empirically-based characterization of a phenomenon of interest (e.g. detailed, critical, analytic account of the evolution of an idea; detailed analytic characterization of a crucial case study or a novel chemical compound, or a new planet)
- Providing a taxonomy of observed phenomena
- Well-founded critique of existing theory or evidence (e.g. correlating the results of a number of existing studies to show patterns, omissions or etc.)