Purpose of our Review
The purpose of our review is to engage the reader in further discourse on this topic of qualitative confirmation. We will use Miller and Fredericks' (M&F) work as a vehicle to initiate debate and demonstrate its usefulness for critiquing published qualitative research studies.
Review Method
Following a review of the historical roots of confirmation theory and a description of M&F's method for establishing qualitative confirmation, we will apply the method to a journal article by Sandra Rubin Glass (1997), an extensive investigation of teacher and principal autonomy in both private and public schools. Her article is an attractive example because she offers readers ready access to much of her original data.
Historical Roots of Qualitative Confirmation
From a historical perspective, M&F take advantage of the logic provided by positivist theories of confirmation (e.g., Carnap, 1962, Hempel, 1965; Swinburne, 1973) and apply it to qualitative research. The authors argue that the use of a hypothesis and numerical probability statements continues to lend weight and credibility to conventional research and they seek to persuade us to transfer elements of the positivist paradigm to qualitative research. They recognize that "confirmation theory" involves complex issues and its application in the postpositivist arena is not a simple matter. Swinburne(1973) claimed that confirming one's findings must be reduced to probability (computational) statements, but M&F suggest that reducing qualitative research to quantitative calculations would overlook the advantages that naturalistic inquiry has to offer. From Carnap (1962), the term "confirmation" involves issues of classification (what is evidence), quantity (how much is good evidence) and comparison (what is the degree of firmness among the evidence).
In M&F's eyes, this raises important questions: whether numericallybased evidence is an option and whether the term confirmation can have different connotations. From Hempel's (1965) constitutive and regulative rules of confirmation, M&F recognize that hypotheses can be further supported by propositions if the propositions are defined legally and/or operationally. Again borrowing from the positivist school, issues related to indeterminacy and incommensurability (Quine, 1963, p.5,9) are introduced. If there is no objective reality and several data collection methods are allowed, triangulation is just as likely to yield contradictory views as it is to produce supportive ones. Which translation manual (2) should one use (indeterminacy)? Similarly, if competing translation theories inform the observations, and therefore cannot logically be used to determine which theory is correct (incommensurability), what does one use to make a decision? Charting the logic underlying one's inquiry process lends validity or correctness to the inferences (see also LeCompte & Preissle, 1993). They do not require translation manuals congruent with one's epistemological and ontological assumptions, but instead prompt the researcher to outline what other translations are possible and determine which one or ones would be valid and why. Most qualitative researchers select their preferred method of inquiry, make a general statement about the data and show a few excerpts; this does not mean, however, that the selected process or the inferences are valid. M&F believe that in every study there is an a priori or a posteriori hypothesis, whether explicitly stated or nor, and that there can and should be a demonstration of how one's epistemological and ontological assumptions, triangulation approach, translation manuals and weighing of evidence link the evidence to that hypothesis. They adapt Hempel's rules to qualitative research (Hempel , 1965) and introduce the term, "qualitative confirmation."
Definition of Qualitative Confirmation
M&F define the term as: "those logical conditions that must obtain between the evidence and hypothesis" (p. 11). The authors admit that the term is an "oxymoronicsounding label" (p.1). However, they argue that their adaptation of the Hempel rules helps decide whether the logic underlying the methods chosen and the sampling and the weighing system for the evidence satisfies the conditions of qualitative confirmation. The rules are also expected to help one minimize the influence of personal bias. M&F recommend a systematic way of conducting and critiquing qualitative research that makes explicit the researcher's process from start to finish and highlights where pitfalls can be prevented. As already noted, one begins with an a priori or a posteriori hypothesis, which may be a transformation of the research question. This emphasis on a hypothesis would seem to set M&F apart from other qualitative research theorists (e.g., Glaser and Strauss, 1967; Stake, 1995), but we think not. See, for example, Strauss and Corbin (1990) on "The Research Question" (pp. 36-39), and Stake, Chapter 2 (pp. 15-33).
The overt thinking that guides the process and the resulting evidenceinstances (3) will ultimately be used to support or reject the hypothesis. This act of specifying one's logic, guided by rules, touches all phases of the qualitative research process; it is a demonstration why the planned activities and resulting evidence support the hypothesis. M&F state: " In other words, qualitative data have to 'demonstrate' their utility as potential evidential candidates for confirmation. It is not simply a matter of amassing positive evidence-instances for a hypothesis, but also showing why they contribute to supporting a given hypothesis" (p. 33, emphasis in original). Thus, qualitative confirmation provides a way of reporting the researcher's thought processes, helps promote a constructivist approach to qualitative research and answers the demand for increased rigor that Miles and Huberman (1984) identify: "Despite a growing interest in qualitative studies, we lack a body of clearly-defined methods for drawing valid meaning from qualitative data. We need methods that are practical, communicable, and not selfdeluding; scientific in the positivist's sense of the word, and aimed toward interpretive understanding in the best sense of that term" (p. 21).