This article needs attention from an expert in research methods. The specific problem is: Case studies have numerous definitions in different fields and are intertwined with similar concepts in those fields.January 2020)(
A case study involves an up-close, in-depth, and detailed examination of a particular case or cases, within a real-world context. For example, case studies in medicine may focus on an individual patient or ailment; case studies in business might cover a particular firm's strategy or a broader market; similarly, case studies in politics can range from a narrow happening over time (e.g., a specific political campaign) to an enormous undertaking (e.g., a World War).
Generally, a case study can highlight nearly any individual, group, organization, event, belief system, or action. A case study does not necessarily have to be one observation (N=1), but may include many observations (one or multiple individuals and entities across multiple time periods, all within the same case study).
Case Study Research Designs
As with other social science methods, no single research design dominates case study research. Case studies can use at least four types of designs. First, there may be a "no theory first" type of case study design, which is closely connected to Kathleen M. Eisenhardt's methodological work. A second type of research design highlights the distinction between single- and multiple-case studies, following Robert K. Yin's guidelines and extensive examples. A third design deals with a "social construction of reality", represented by the work of Robert E. Stake. Finally, the design rationale for a case study may be to identify "anomalies". A representative scholar of this design is Michael Burawoy. Each of these four designs may lead to different applications, and understanding their sometimes unique ontological and epistemological assumptions becomes important. However, although the designs can have substantial methodological differences, the designs also can be used in explicitly acknowledged combinations with each other.
While case studies can be intended to provide bounded explanations of single cases or phenomena, they are often intended to theoretical insights about the features of a broader population.
Case Selection and Structure
Case selection in case study research is generally intended to both find cases that are a representative sample and which have variations on the dimensions of theoretical interest. Using that is solely representative, such as an average or typical case is often not the richest in information. In clarifying lines of history and causation it is more useful to select subjects that offer an interesting, unusual or particularly revealing set of circumstances. A case selection that is based on representativeness will seldom be able to produce these kinds of insights.
While random selection of cases is a valid case selection strategy in large-N research, there is a consensus among scholars that it risks generating serious biases in small-N research. Cases should generally be chosen that have a high expected information gain. For example, outlier cases (those which are extreme, deviant or atypical) can reveal more information than the potentially representative case. A case may also be chosen because of the inherent interest of the case or the circumstances surrounding it. Alternatively it may be chosen because of researchers' in-depth local knowledge; where researchers have this local knowledge they are in a position to "soak and poke" as Richard Fenno put it, and thereby to offer reasoned lines of explanation based on this rich knowledge of setting and circumstances.
Beyond decisions about case selection and the subject and object of the study, decisions need to be made about purpose, approach and process in the case study. Gary Thomas thus proposes a typology for the case study wherein purposes are first identified (evaluative or exploratory), then approaches are delineated (theory-testing, theory-building or illustrative), then processes are decided upon, with a principal choice being between whether the study is to be single or multiple, and choices also about whether the study is to be retrospective, snapshot or diachronic, and whether it is nested, parallel or sequential.
John Gerring and Jason Seawright list seven case selection strategies:
- Typical cases are cases that exemplify a stable cross-case relationship. These cases are representative of the larger population of cases, and the purpose of the study is to look within the case rather than compare it with other cases.
- Diverse cases are cases that have variation on the relevant X and Y variables. Due to the range of variation on the relevant variables, these cases are representative of the full population of cases.
- Extreme cases are cases that have an extreme value on the X or Y variable relative to other cases.
- Deviant cases are cases that defy existing theories and common sense. They not only have extreme values on X or Y (like extreme cases), but defy existing knowledge about causal relations.
- Influential cases are cases that are central to a model or theory (for example, Nazi Germany in theories of fascism and the far-right).
- Most similar cases are cases that are similar on all the independent variables, except the one of interest to the researcher.
- Most different cases are cases that are different on all the independent variables, except the one of interest to the researcher.
For theoretical discovery, Jason Seawright recommends using deviant cases or extreme cases that have an extreme value on the X variable.
- In atheoretical (or configurative idiographic) case studies the goal is to describe a case very well, but not to contribute to a theory.
- In interpretative (or disciplined configurative) case studies the goal is to use established theories to explain a specific case.
- In hypothesis-generating (or heuristic) case studies the goal is to inductively identify new variables, hypotheses, causal mechanisms and causal paths.
- In theory testing case studies the goal is to assess the validity and scope conditions of existing theories.
- In plausibility probes the goal is to assess the plausibility of new hypotheses and theories.
- In building block studies of types or subtypes the goal is to identify common patterns across cases.
In terms of case selection, Gary King, Robert Keohane, and Sidney Verba warn against "selecting on the dependent variable". They argue for example that researchers cannot make valid causal inferences about war outbreak by only looking at instances where war did happen (the researcher should also look at cases where war did not happen). Scholars of qualitative methods have disputed this claim, however. They argue that selecting on the dependent variable can be useful depending on the purposes of the research. Barbara Geddes shares KKV's concerns with selecting on the dependent variable (she argues that it cannot be used for theory testing purposes), but she argues that selecting on the dependent variable can be useful for the purposes of theory creation and theory modification.
King, Keohane and Verba argue that there is no methodological problem in selecting on the explanatory variable, however. They do warn about multicollinearity (choosing two or more explanatory variables that perfectly correlate with each other).
Uses and Limits
Case studies have commonly been seen as a fruitful way to come up hypotheses and generate theories. Case studies are also useful for formulating concepts, which are an important aspect of theory construction. The concepts used in qualitative research will tend to have higher conceptual validity than concepts used in quantitative research (due to conceptual stretching: the unintentional comparison of dissimilar cases). Case studies add descriptive richness. Case studies are suited to explain outcomes in individual cases, which is something that quantitative methods are less equipped to do. Through fine-gained knowledge and description, case studies can fully specify the causal mechanisms in a way that may be harder in a large-N study. In terms of identifying "causal mechanisms", some scholars distinguish between "weak" and "strong chains". Strong chains actively connect elements of the causal chain to produce an outcome whereas weak chains are just intervening variables.
Case studies of cases that defy existing theoretical expectations may contribute knowledge by delineating why the cases violate theoretical predictions and specifying the scope conditions of the theory. Case studies are useful in situations of causal complexity where there is equifinality, complex interaction effects and path dependency. Case studies can identify necessary and insufficient conditions, as well as complex combinations of necessary and sufficient conditions. They argue that case studies may also be useful in identifying the scope conditions of a theory: whether variables are sufficient or necessary to bring about an outcome.
Designing Social Inquiry, an influential 1994 book written by Gary King, Robert Keohane, and Sidney Verba, primarily applies lessons from regression-oriented analysis to qualitative research, arguing that the same logics of causal inference can be used in both types of research. The authors' recommendation is to increase the number of observations (a recommendation that Barbara Geddes also makes in Paradigms and Sand Castles), because few observations make it harder to estimate multiple causal effects, as well as increase the risk that there is measurement error, and that an event in a single case was caused by random error or unobservable factors. KKV sees process-tracing and qualitative research as being "unable to yield strong causal inference" due to the fact that qualitative scholars would struggle with determining which of many intervening variables truly links the independent variable with a dependent variable. The primary problem is that qualitative research lacks a sufficient number of observations to properly estimate the effects of an independent variable. They write that the number of observations could be increased through various means, but that would simultaneously lead to another problem: that the number of variables would increase and thus reduce degrees of freedom.
The purported "degrees of freedom" problem that KKV identify is widely considered flawed; while quantitative scholars try to aggregate variables to reduce the number of variables and thus increase the degrees of freedom, qualitative scholars intentionally want their variables to have many different attributes and complexity. For example, James Mahoney writes, "the Bayesian nature of process tracing explains why it is inappropriate to view qualitative research as suffering from a small-N problem and certain standard causal identification problems." By using Bayesian probability, it may be possible to makes strong causal inferences from a small sliver of data.
As small-N research should not rely on random sampling, scholars must be careful in avoiding selection bias when picking suitable cases. A common criticism of qualitative scholarship is that cases are chosen because they are consistent with the scholar's preconceived notions, resulting in biased research.
Alexander George and Andrew Bennett note that a common problem in case study research is that of reconciling conflicting interpretations of the same data.
Teaching case studies
Teachers may prepare a case study that will then be used in classrooms in the form of a "teaching" case study (also see case method and casebook method). For instance, as early as 1870 at Harvard Law School, Christopher Langdell departed from the traditional lecture-and-notes approach to teaching contract law and began using cases pled before courts as the basis for class discussions. By 1920, this practice had become the dominant pedagogical approach used by law schools in the United States.
Outside of law, teaching case studies have become popular in many different fields and professions, ranging from business education to science education. The Harvard Business School has been among the most prominent developers and users of teaching case studies. Teachers develop case studies with particular learning objectives in mind. Additional relevant documentation, such as financial statements, time-lines, short biographies, and multimedia supplements (such as video-recordings of interviews) often accompany the case studies. Similarly, teaching case studies have become increasingly popular in science education, covering different biological and physical sciences. The National Center for Case Studies in Teaching Science has made a growing body of teaching case studies available for classroom use, for university as well as secondary school coursework.
- Bromley, D.B. (1986) The Case-Study Method in Psychology and Related Disciplines. (Chichester, England: Wiley)|ISBN-13=978-0471908531
- Feagin, J.R. Orum, A.M., & Sjoberg, G. (Eds.)(1991). A Case for the Case Study. (Chapel Hill, NC: University of North Carolina Press)|ISBN 978-0807843215
- Geddes, Barbara (2003). Paradigms and Sand Castles. Ann Arbor, MI: University of Michigan Press. p. 117. doi:10.3998/mpub.11910. ISBN 978-0-472-09835-4.
- King, Gary; Keohane, Robert O.; Verba, Sidney (1994). Designing Social Inquiry. Princeton, New Jersey: Princeton University Press. pp. 52–53. doi:10.1515/9781400821211. ISBN 978-1-4008-2121-1.
- Thies, Cameron G. (2002). "A Pragmatic Guide to Qualitative Historical Analysis in the Study of International Relations". International Studies Perspectives. 3 (4): 351–372. ISSN 1528-3577.
- Mills, Albert J.; Durepos, Gabrielle; Wiebe, Elden, eds. (2010). Encyclopedia of Case Study Research. Thousand Oaks, CA: SAGE Publications. p. xxxi. ISBN 978-1-4129-5670-3.
- Yin, Robert K. (2018). Case Study Research: Design and Methods (6th ed.). Thousand Oaks, CA: SAGE Publications. ISBN 978-1-5063-3616-9.
- Rolls, Geoffrey (2005). Classic Case Studies in Psychology. Abingdon, England: Hodder Education.
- Taylor, Marilyn L. and Søndergaard, Mikael (2017). Unraveling the Mysteries of Case Study Research: A Guide for Business and Management Students. Edward Elgar Publishing. ISBN 978-1786437235.
- Ridder, Hans-Gerd (October 2017). "The theory contribution of case study research designs". Business Research. 10 (2): 281–305. doi:10.1007/s40685-017-0045-z. ISSN 2198-2627.
- Eisenhardt, Kathleen M. (1991). "Better Stories and Better Constructs: The Case for Rigor and Comparative Logic". The Academy of Management Review. 16 (3): 620–627. doi:10.5465/amr.1991.4279496. JSTOR 258921.
- Stake, Robert E. (1995). The Art of Case Study Research. Thousand Oaks, CA: SAGE Publications. pp. 99–102. ISBN 978-0-8039-5767-1.
- Burawoy, Michael (2009). The Extended Case Method: Four Countries, Four Decades, Four Great Transformations, and One Theoretical Tradition. Berkeley: University of California Press. ISBN 978-0-520-94338-4.
- Seawright, Jason; Gerring, John (2014), "Case Selection Techniques in Case Study Research: A Menu of Qualitative and Quantitative Options", Political Research Quarterly, doi:10.4135/9781473915480.n31, ISBN 978-1-4462-7448-4
- Levy, Jack (2014), "Case Studies: Types, Designs, and Logics of Inference", Case Studies, SAGE Publications Ltd, pp. II113, doi:10.4135/9781473915480.n26, ISBN 978-1-4462-7448-4
- King, Gary/ Keohane, Robert O./ Verba, Sidney: Designing Social Inquiry. Scientific Inference in Qualitative Research. Princeton University Press, 1994.
- Flyvbjerg, Bent (2007). "Five Misunderstandings About Case-Study Research Inquiry". In Seale, Clive; Silverman, David; Gobo, Giampietro; Gubrium, Jaber F. (eds.). Qualitative Research Practice: Concise Paperback Edition. Qualitative Inquiry. 12. Thousand Oaks, CA: SAGE Publications. p. 390. arXiv:1304.1186. doi:10.1177/1077800405284363. ISBN 978-1-4129-3420-6. S2CID 62807147.
- George, Alexander L.; Bennett, Andrew (2005). Case Studies and Theory Development in the Social Sciences. MIT Press. ISBN 978-0-262-30307-1. OCLC 944521872.
- Seawright, Jason (2016), "Case Selection after Regression", Multi-Method Social Science: Combining Qualitative and Quantitative Tools, Cambridge University Press, pp. 75–106, doi:10.1017/cbo9781316160831.004, ISBN 978-1-107-09771-1, retrieved 2021-02-11
- Huang, Huayi (2015). Development of New Methods to Support Systemic Incident Analysis (PDF) (Doctoral dissertation). London: Queen Mary University.[page needed]
- Underwood, Peter; Waterson, Patrick; Braithwaite, Graham (2016). "'Accident investigation in the wild' – A small-scale, field-based evaluation of the STAMP method for accident analysis". Safety Science. 82: 129–43. doi:10.1016/j.ssci.2015.08.014.
- Fenno, Richard F. (2014). "Observation, Context, and Sequence in the Study of Politics". American Political Science Review. 80 (1): 3–15. doi:10.2307/1957081. JSTOR 1957081.
- Thomas, Gary (2011). "A Typology for the Case Study in Social Science Following a Review of Definition, Discourse, and Structure". Qualitative Inquiry. 17 (6): 511–21. doi:10.1177/1077800411409884. S2CID 144895919.
- George, Alexander L.; Bennett, Andrew (2005). Case Studies and Theory Development in the Social Sciences. MIT Press. pp. 74–76, 213. ISBN 978-0-262-30307-1. OCLC 944521872.
- Goertz, Gary; Mahoney, James (2012-09-09). A Tale of Two Cultures. Princeton University Press. pp. 221–227. ISBN 978-0-691-14970-7.
- Brady, Henry E. Collier, David (2010). Rethinking social inquiry : diverse tools, shared standards (2 ed.). Rowman & Littlefield Publishers. ISBN 1-4422-0343-9. OCLC 838295613.CS1 maint: multiple names: authors list (link)
- Geddes, Barbara (2003). Paradigms and Sand Castles: Theory Building and Research Design in Comparative Politics. University of Michigan Press. pp. 129–139. doi:10.3998/mpub.11910. ISBN 978-0-472-09835-4. JSTOR 10.3998/mpub.11910.
- Flyvbjerg, Bent; Flyvbjerg, Bent (2014), "Five Misunderstandings About Case-Study Research" (PDF), Case Studies, SAGE Publications Ltd, pp. III33, doi:10.4135/9781473915480.n40, ISBN 978-1-446274484
- Mahoney, James (2010). "After KKV: The New Methodology of Qualitative Research". World Politics. 62 (1): 120–147. doi:10.1017/S0043887109990220. ISSN 1086-3338. S2CID 43923978.
- Collier, David (2011). "Understanding Process Tracing". PS: Political Science & Politics. 44 (4): 823–830. doi:10.1017/s1049096511001429. ISSN 1049-0965.
- Bennett, Andrew; Elman, Colin (2006). "Qualitative Research: Recent Developments in Case Study Methods". Annual Review of Political Science. 9 (1): 455–476. doi:10.1146/annurev.polisci.8.082103.104918. ISSN 1094-2939.
- Braumoeller, Bear and Anne Sartori. 2004. “The Promise and Perils of Statistics in International Relations.” in Cases, Numbers, Models: International Relations Research Methods. Ann Arbor: University of Michigan Press: ch. 6.
- Waldner, David (2015-06-22). "Process Tracing and Qualitative Causal Inference". Security Studies. doi:10.1080/09636412.2015.1036624. ISSN 0963-6412.
- Humphreys, Macartan; Jacobs, Alan M. (2015). "Mixing Methods: A Bayesian Approach". American Political Science Review. 109 (4): 654. doi:10.1017/s0003055415000453. ISSN 0003-0554.
- Bennett, Andrew (2008-08-21). "Process Tracing: a Bayesian Perspective". The Oxford Handbook of Political Methodology. doi:10.1093/oxfordhb/9780199286546.001.0001/oxfordhb-9780199286546-e-30. Retrieved 2021-02-19.
- Mahoney, James (2016-09-02). "Mechanisms, Bayesianism, and process tracing". New Political Economy. 21 (5): 493–499. doi:10.1080/13563467.2016.1201803. ISSN 1356-3467.
- Bennett, Andrew (2008). "Process Tracing: a Bayesian Perspective". The Oxford Handbook of Political Methodology. doi:10.1093/oxfordhb/9780199286546.001.0001/oxfordhb-9780199286546-e-30.
- Kimball, B. A. (2009). The Inception of Modern Professional Education: C. C. Langdell, 1826–1906 (Chapel Hill: University of North Carolina Press, 2009)[page needed]
- Jackson, Giles (2011). "Rethinking the case method". Journal of Management Policy and Practice. 12 (5): 142–64.
- Garvin, David A. (2003). "Making the Case: Professional Education for the World of Practice". Harvard Magazine. 106 (1): 56–107.
- Ellet, W. (2007). The Case Study Handbook: How to Read, Write, and Discuss Persuasively about Cases. Boston, MA: Harvard Business School Press. ISBN 978-1-422-10158-2.[page needed]
- Palmer, Grier; Iordanou, Ioanna (2015). Exploring Cases Using Emotion, Open Space and Creativity. Case-based Teaching and Learning for the 21st Century. Libri. pp. 19–38. ISBN 978-1-909818-57-6.
- Herreid, Clyde F.; Schiller, Nancy A.; Wright, Carolyn; Herreid, Ky (eds.). "About Us". National Center for Case Study Teaching in Science (NCCSTS). University at Buffalo. Retrieved 2018-09-12.
- Baskarada, Sasa (October 19, 2014). "Qualitative Case Study Guidelines". The Qualitative Report. 19 (40): 1–25. SSRN 2559424.
- Bartlett, L. and Vavrus, F. (2017). Rethinking Case Study Research. Routledge.
- Baxter, Pamela; Jack, Susan (2008). "Qualitative Case Study Methodology: Study Design and Implementation for Novice Researchers". The Qualitative Report. 13 (4): 544–59.
- Eisenhardt, Kathleen M. (1989). "Building Theories from Case Study Research". The Academy of Management Review. 14 (4): 532–50. doi:10.2307/258557. JSTOR 258557.
- George, Alexander L. and Bennett, Andrew. (2005) Case studies and theory development in the social sciences. MIT Press. ISBN 0-262-57222-2
- Gerring, John. (2005) Case Study Research. New York: Cambridge University Press. ISBN 978-0-521-67656-4
- Kyburz-Graber, Regula (2004). "Does case-study methodology lack rigour? The need for quality criteria for sound case-study research, as illustrated by a recent case in secondary and higher education". Environmental Education Research. 10 (1): 53–65. doi:10.1080/1350462032000173706.
- Mills, Albert J.; Durepos, Gabrielle; Wiebe, Elden, eds. (2010). Encyclopedia of Case Study Research. SAGE Publications. ISBN 978-1-4129-5670-3.
- Ragin, Charles C. and Becker, Howard S. Eds. (1992) What is a Case? Exploring the Foundations of Social Inquiry. Cambridge University Press. ISBN 0-521-42188-8
- Scholz, Roland W. and Tietje, Olaf. (2002) Embedded Case Study Methods. Integrating Quantitative and Qualitative Knowledge. Sage. ISBN 0-7619-1946-5
- Straits, Bruce C. and Singleton, Royce A. (2004) Approaches to Social Research, 4th ed. Oxford University Press. ISBN 0-19-514794-4.
- Thomas, Gary (2011). How to Do Your Case Study: A Guide for Students and Researchers. SAGE Publications.
- Yin, Robert K. (2018). Case Study Research and Applications: Design and Methods (6th ed.). SAGE Publications. ISBN 978-1-5063-3616-9.
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