CASE STUDY RESEARCH Design and Methods Second Edition Robert K. Yin Applied Social Research Methods Series Volume 5 SAGE Publications International Educational and Professional Publisher Thousand Oaks London New Delhi Introduction The case study is but one of several ways of doing social science research. Other ways include experiments, surveys, histories, and the analysis of archival information (as in economic studies). Each strategy has peculiar advantages and disadvantages, depending upon three conditions: (a) the type of research question, (b) the control an investigator has over actual behavioral events, and (c) the focus on contemporary as opposed to historical phenomena. In general, case studies are the preferred strategy when "how" or "why" questions are being posed, when the investigator has little control over events, and when the focus is on a contemporary phenomenon within some real-life context. Such "explanatory" case studies also can be complemented by two other types—"exploratory1* and "descriptive" case studies. Regardless of the type of case study, investigators must exercise great care in designing and doing case studies to overcome the traditional criticisms of the method. THE CASE STUDY AS A RESEARCH STRATEGY This book is about the design and conduct of case studies for research purposes. As a research strategy, the case study is used in many situations, including: • Policy, political science, and public administration research • Community psychology and sociology • Organizational and management studies • City and regional planning research, such as studies of plans, neighborhoods, or public agencies • The conduct of dissertations and theses in the social sciences—the academic disciplines as well as professional fields such as business administration, management science, and social work This book covers the distinctive characteristics of the case study strategy, compared with other types of research. Importantly, the book deals with 1 2 CASE STUDY RESEARCH design, analysis, and reporting issues—and not merely the more traditional focus on data collection or fieldwork. The overall goal of this book is to help investigators deal with some of the more difficult questions commonly neglected by available research texts. So often, for instance, the author has been confronted by a student or colleague who has asked (a) how to define the case being studied, (b) how to determine the relevant data to be collected, or (c) what should be done with the data, once collected. This book, it is hoped, answers these questions. However, this book does not cover all uses of case studies. For example, it is not intended to help those who might use case studies as teaching devices, popularized in the fields of law, business, medicine, or public policy (see Llewellyn, 1948; Stein, 1952; Towl, 1969; Windsor & Greanias, 1983) but now prevalent in virtually every academic field, including the natural sciences. For teaching purposes, a case study need not contain a complete or accurate rendition of actual events; rather, its purpose is to establish a framework for discussion and debate among students. The criteria for developing good cases for teaching—usually of the single- and not multiple-case variety—are far different than those for doing research (e.g., Caulley & Dowdy, 1987). Teaching case studies need not be concerned with the rigorous and fair presentation of empirical data; research case studies need to do exactly that. Similarly, this book is not intended to cover those situations in which cases are used as a form of record keeping. Medical records, social work files, and other case records are used to facilitate some practice, such as medicine, law, or social work. Again, the criteria for developing good cases for practice are different than those for designing case studies for research. In contrast, the rationale for this book is that case studies are increasingly used as a research tool (e.g., Hamel, 1992; Perry & Kraemer, 1986) and that you—who may be a seasoned or budding social scientist—would like to know how to design and conduct single- or multiple-case studies to investigate a research issue. This book concentrates heavily on the problem of designing and analyzing case studies and is not merely a guide to collecting case study evidence. In this sense, the book fills a void in social science methodology, which is dominated by texts on 'Tield methods " offering few guides on how to start a case study, how to analyze the data, or even how to minimize the problems of composing the case study report. This book covers all of the phases of design, data collection, analysis, and reporting. As a research endeavor, the case study contributes uniquely to our knowledge of individual, organizational, social, and political phenomena. Not surprisingly, the case study has been a common research strategy in psychology, sociology, political science, business, social work, and planning (Yin, INTRODUCTION 3 1983), Case studies are even found in economics, in which the structure of a given industry, or the economy of a city or a region, may be investigated by using a case study design. In all of these situations, the distinctive need for case studies arises out of the desire to understand complex social phenomena. In brief, the case study allows an investigation to retain the holistic and meaningful characteristics of real-life events—such as individual life cycles, organizational and managerial processes, neighborhood change, international relations, and the maturation of industries. COMPARING CASE STUDIES WITH OTHER RESEARCH STRATEGIES When and why would you want to do case studies on some topic? Should you consider doing an experiment instead? A survey ? A history? A computer-based analysis of archival records such as student records? These and other choices represent different research strategies. (The following discussion focuses only on five choices and does not attempt to catalog all of them, however.) Each is a different way of collecting and analyzing empirical evidence, following its own logic. And each strategy has its own advantages and disadvantages. To get the most out of using the case study strategy, you need to know these differences. A common misconception is that the various research strategies should be arrayed hierarchically. We were once taught to believe that case studies were appropriate for the exploratory phase of an investigation, that surveys and histories were appropriate for the descriptive phase, and that experiments were the only way of doing explanatory or causal inquiries. The hierarchical view reinforced the idea that case studies were only an exploratory tool and could not be used to describe or test propositions (Piatt, 1992a). This hierarchical view, however, is incorrect. Experiments with an exploratory motive have certainly always existed. In addition, the development of causal explanations has long been a serious concern of historians, reflected by the subfield known as historiography. Finally, case studies are far from being only an exploratory strategy. Some of the best and most famous case studies have been both descriptive (for example, Whyte's Street Corner Society, 1943/1955; see BOX 1) and explanatory (see Allison's Essence of Decision: Explaining the Cuban Missile Crisis, 1971 [emphasis added to title]; see BOX 2). The more appropriate view of these different strategies is a pluralistic one. Each strategy can be used for all three purposes—exploratory, descriptive, or 4 CASE STUDY RESEARCH BOX1 A Famous Descriptive Case Study Street Corner Society (1943/1955), by William R Whyte, has for decades been recommended reading in community sociology. The book is a classic example of a descriptive case study. Thus it traces the sequence of interpersonal events over time, describes a subculture that had rarely been the topic of previous study, and discovers key phenomena—such as the career advancement of lower income youths and their ability (or inability) to break neighborhood ties. The study has been highly regarded despite its being a single-case study, covering one neighborhood ("Cornerville") and a time period now more than 50 years old. The value of the book is, paradoxically, its generalizability to issues on individual performance, group structure, and the social structure of neighborhoods. Later investigators have repeatedly found remnants of Cornerville in their work, even though they have studied different neighborhoods and different time periods. explanatory. There may be exploratory case studies, descriptive case studies, or explanatory case studies (Yin, 1981a, 1981b). There also may be exploratory experiments, descriptive experiments, and explanatory experiments. What distinguishes the strategies is not this hierarchy but three other conditions, discussed below. Nevertheless, this does not imply that the boundaries between the strategies—or the occasions when each is to be used—are always clear and sharp. Even though each strategy has its distinctive characteristics, there are large areas of overlap among them (e,g.t Sieber, 1973). The goal is to avoid gross misfits—that is, when you are planning to use one type of strategy but another is really more advantageous. When to Use Each Strategy The three conditions consist of (a) the type of research question posed, (b) the extent of control an investigator has over actual behavioral events, and (c) the degree of focus on contemporary as opposed to historical events. Figure 1.1 displays these three conditions and shows how each is related to five major research strategies in the social sciences: experiments, surveys, archival analysis, histories, and case studies. The importance of each condition, in distinguishing among the five strategies, is discussed below. INTRODUCTION 5 BOX 2 An Explanatory Case Study Even a single-case study can often be used to pursue an explanatory, and not merely exploratory (or descriptive), purpose. The analyst's objective should be to pose competing explanations for the same set of events and to indicate how such explanations may apply to other situations. This strategy was followed by Graham Allison in Essence of Decision: Explaining the Cuban Missile Crisis (1971). The single case is the confrontation between the United States and the Soviet Union over the placement of offensive missiles in Cuba. Allison posits three competing theories or models to explain the course of events, including answers to three key questions: why the Soviet Union placed offensive (and not merely defensive) missiles in Cuba in the first place, why the United States responded to the missile deployment with a blockade (and not an air strike or invasion), and why the Soviet Union eventually withdrew the missiles. By comparing each theory with the actual course of events, Allison develops the best explanation for this type of crisis. Allison suggests that this explanation is applicable to other situations, thereby extending the usefulness of his single-case study. Thus Allison cites the U.S. involvement in Vietnam, nuclear confrontation more generally, and the termination of wars by nations as other situations for which the theory can offer useful explanation. Types of research questions (Figure 1.1, column 1). The first condition covers your research questions) (Hedrick, Bickman, & Rog, 1993). A basic categorization scheme for the types of questions is the familiar series: 'Vho," "what," "where," "how," and "why." If research questions focus mainly on **what" questions, either of two. possibilities arises. First, some types of "what" questions are exploratory, such as this one: "What are the ways of making schools effective?" This type of question is a justifiable rationale for conducting an exploratory study, the goal being to develop pertinent hypotheses and propositions for further inquiry. However, as an exploratory study, any of the five research strategies can be used—for example, an exploratory survey, an exploratory experiment, or an exploratory case study. The second type of "what" question is actually a form of a "how many" or "how much" line of inquiry—for example, "What have been the outcomes from a particular managerial reorganization?" Identifying such outcomes is more likely to favor survey or archival strategies than others. For example, a survey can be readily designed to enumerate the 6 CASE STUDY RESEARCH strategy farm of research question requires control over behavioral eventsT focuses on contemporary events? experiment faowi why yes yes surrey who, what, wiiere, hownuaj, how much no yes archival analysis who> what, where* how ntany> how mach no yes/no hlilory how* why - no esse a lady how* why no yes Figure 1.1. Relevant Situations for Different Research Strategies SOURCE: COSMOS Corporation. "whats," whereas a case study would not be an advantageous strategy in this situation. Similarly, like this second type of 4twhať' question, "who" and "where" questions (or their derivatives—"how many" and "how much") are likely to favor survey strategies or the analysis of archival records, as in economic research. These strategies are advantageous when the research goal is to describe the incidence or prevalence of a phenomenon or when it is to be predictive about certain outcomes. The investigation of prevalent political attitudes (in which a survey or a poll might be the favored strategy) or of the spread of a disease like AIDS (in which an analysis of health statistics might be the favored strategy) would be typical examples. In contrast, "how" and "why" questions are more explanatory and likely to lead to the use of case studies, histories, and experiments as the preferred research strategies. This is because such questions deal with operational links needing to be traced over time, rather than mere frequencies or incidence. Thus, if you wanted to know how a community successfully thwarted a proposed highway (see Lupo et al, 1971), you would be less likely to rely on a survey or an examination of archival records and might be better off doing a history or a case study. Similarly, if you wanted to know why bystanders fail to report emergencies under certain conditions, you could design and conduct a series of experiments (see Látané & Dariey, 1969). INTRODUCTION 7 Let us take two more examples. If you were studying "who" participated in riots, and "how much" damage had been done, you might survey residents, examine business records (an archival analysis), or conduct a "windshield survey*' of the riot area. In contrast, if you wanted to know "why" riots occurred, you would have to draw upon a wider array of documentary information, in addition to conducting interviews; if you focused on the "why" question in more than one city, you would probably be doing a multiple-case study. Similarly, if you wanted to know "what" the outcomes of a new governmental program had been, you could answer this frequency question by doing a survey or by examining economic data, depending upon the type of program involved. Thus consider such questions as these: How many clients did the program serve? What kinds of benefits were received? How often were different benefits produced? These could all be answered without doing a case study. But if you needed to know "how" or "why" the program had worked (or not), you would lean toward either a case study or a field experiment. Some "how" and "why" questions are ambivalent and need clarification. "How" and "why" Bill Clinton got elected in 1992 can be studied by either a survey or a case study. The survey migjit examine voting patterns, showing that voters for Ross Perot drew largely from supporters of then President Bush, and this could satisfactorily address the how and why questions. In contrast, the case study might examine how Clinton conducted his campaign to achieve the necessary nomination and to manipulate public opinion in his favor. The study would cover the potentially helpful role of the weak U.S. economy in denying support for the Bush-Quayle ticket as incumbents. This approach also would be an acceptable way of addressing the "how" and "why" questions but would be different than the survey study. To summarize, the first and most important condition for differentiating among the various research strategies is to identify the type of research question being asked. In general, **what" questions may either be exploratory (in which case any of the strategies could be used) or about prevalence (in which surveys or the analysis of archival records would be favored). "How" and "why" questions are likely to favor the use of case studies, experiments, or histories. Defining the research questions is probably the most important step to be taken in a research study, so patience and sufficient time should be allowed for this task. The key is to understand that research questions have both substance—for example, What is my study about?—andform—for example, Am I asking a "who," "what," "where," "why" or "how" question? Others have focused on some of the substantively important issues (see Campbell, 8 CASE STUDY RESEARCH Daft, & Hulin, 1982); the point of the preceding discussion is that the form of the question provides an important clue regarding the appropriate research strategy to be used. Remember, too, the large areas of overlap among the strategies, so that, for some questions, a choice among strategies might actually exist. Remember, finally, that you may be predisposed to pursue a particular strategy regardless of the study question. If so, be sure to create the form of the study question best matching the strategy you were inclined to pursue in the first place. Extent of control over behavioral events (Figure 1.1, column 2) and degree of focus on contemporary as opposed to historical events (Figure J. lt column 3). Assuming that "how" and "why" questions are to be the focus of study, a further distinction among history, case study, and experiment is the extent of the investigator's control over and access to actual behavioral events. Histories are the preferred strategy when there is virtually no access or control. Thus the distinctive contribution of the historical method is in dealing with the "dead" past—that is, when no relevant persons are alive to report, even retrospectively, what occurred, and when an investigator must rely on primary documents, secondary documents, and cultural and physical artifacts as the main sources of evidence. Histories can, of course, be done about contemporary events; in this situation, the strategy begins to overlap with that of the case study. The case study is preferred in examining contemporary events, but when the relevant behaviors cannot be manipulated. The case study relies on many of the same techniques as a history, but it adds two sources of evidence not usually included in the historian's repertoire: direct observation and systematic interviewing. Again, although case studies and histories can overlap, the case study's unique strength is its ability to deal with a full variety of evidence—documents, artifacts, interviews, and observations—beyond what might be available in the conventional historical study. Moreover, in some situations, such as participant-observation, informal manipulation can occur. Finally, experiments are done when an investigator can manipulate behavior directly, precisely, and systematically. This can occur in a laboratory setting, in which an experiment may focus on one or two isolated variables (and presumes that the laboratory environment can "contror* for all the remaining variables beyond the scope of interest), or it can be done in a field setting, where the term social experiment has emerged to cover research in which investigators "treat" whole groups of people in different ways, such as providing them with different kinds of vouchers (Boruch, forthcoming). Again, the methods overlap. The full range of experimental science also INTRODUCTION 9 includes those situations in which the experimenter cannot manipulate behavior (see Blalock, 1961; Campbell & Stanley, 1966; Cook & Campbell, 1979) but in which the logic of experimental design may still be applied. These situations have been commonly regarded as "quasi-experimental" situations. The quasi-experimental approach can even be used in a historical setting, in which, for instance, an investigator may be interested in studying race riots or lynchings (see Spilerman, 1971) and may use a quasi-experimental design because no control over the behavioral event was possible. Summary. We can identify some situations in which all research strategies might be relevant (such as exploratory research), and other situations in which two strategies might be considered equally attractive (such as how and why Clinton got elected). We also can use more than one strategy in any given study (for example, a survey within a case study or a case study within a survey). To this extent, the various strategies are not mutually exclusive. But we can also identify some situations in which a specific strategy has a distinct advantage. For the case study, this is when • a "how" or "why" question is being asked about a contemporary set of events over which the investigator has little or no control. To determine the questions that are most significant for a topic, and to gain some precision in formulating these questions, requires much preparation. One way is to review the literature on the topic (Cooper, 1984). Note that such a literature review is therefore a means to an end, and not—as most students think—an end in itself. Budding investigators think that the purpose of a literature review is to determine the answers about what is known on a topic; in contrast, experienced investigators review previous research to develop sharper and more insightful questions about the topic. Traditional Prejudices Against the Case Study Strategy Although the case study is a distinctive form of empirical inquiry, many research investigators nevertheless have disdain for the strategy. In other words, as a research endeavor, case studies have been viewed as a less desirable form of inquiry than either experiments or surveys. Why is this? Perhaps the greatest concern has been over the lack of rigor of case study research. Too many times, the case study investigator has been sloppy and has allowed equivocal evidence or biased views to influence the direction of the findings and conclusions. 10 CASE STUDY RESEARCH The possibility also exists that people have confused case study teaching with case study research. In teaching, case study materials may be deliberately altered to demonstrate a particular point more effectively. In research, any such step would be strictly forbidden. Every case study investigator must work hard to report all evidence fairly, and this book will help him or her to do so. What is often forgotten is that bias also can enter into the conduct of experiments (see Rosenthal, 1966) and the use of other research strategies, such as designing questionnaires for surveys (Sudman & Bradburn, 1982) or conducting historical research (Gottschalk, 1968). The problems are not different, but in case study research, they may have been more frequently encountered and less frequently overcome. A second common concern about case studies is that they provide little basis for scientific generalization. "How can you generalize from a single case?" is a frequently heard question. The answer is not a simple one (Kennedy, 1976). However, consider for the moment that the same question had been asked about an experiment: "How can you generalize from a single experiment?" In fact, scientific facts are rarely based on single experiments; they are usually based on a multiple set of experiments, which have replicated the same phenomenon under different conditions. The same approach can be used with multiple-case studies but requires a different concept of the appropriate research designs; this is discussed in detail in Chapter 2. The short answer is that case studies, like experiments, are generalizable to theoretical propositions and not to populations or universes. In this sense, the case study, like the experiment, does not represent a "sample " and the investigator's goal is to expand and generalize theories (analytic generalization) and not to enumerate frequencies (statistical generalization). Or, as three notable social scientists describe in their single case study, the goal is to do a "generalizing" and not a "particularizing" analysis (Lipset, Trow, & Coleman, 1956, pp. 419-420). A third frequent complaint about case studies is that they take too long, and they result in massive, unreadable documents. This complaint may be appropriate, given the way case studies have been done in the past (e.g., Feagin, Oram, & Sjoberg, 1991), but this is not necessarily the way case studies must be done in the future. Chapter 6 discusses alternative ways of writing the case study—including ones in which the traditional, lengthy narrative can be avoided altogether. Nor need case studies take a long time. This incorrectly confuses the case study strategy with a specific method of data collection, such as ethnography or participant-observation. Ethnographies usually require long periods of time in the "field" and emphasize detailed, observational evidence. Participant-observation may not require the INTRODUCTION 11 same length of time but still assumes a hefty investment of field efforts. In contrast, case studies are a form of inquiry that does not depend solely on ethnographic or participant-observer data. One could even do a valid and high-quality case study without leaving the library and the telephone, depending upon the topic being studied. Despite the fact that these common concerns can be allayed, as above, one major lesson is still that good case studies are very difficult to do. The problem is that we have little way of screening or testing for an investigator's ability to do good case studies. People know when they cannot play music; they also know when they cannot do mathematics; and they can be tested for other skills, such as by the bar examination in law. Somehow, the skills for doing good case studies have not yet been defined, and as a result, most people feel that they can prepare a case study, and nearly all of us believe we can understand one. Since neither view is well founded, the case study receives a good deal of approbation it does not deserve. (Hoaglin, Light, McPeek, Mosteller, & Stoto, 1982, p. 134) This quotation is from a book by five prominent statisticians. Surprisingly, even from another field, they recognize the challenge of doing good case studies. DIFFERENT TYPES OF CASE STUDIES, BUT A COMMON DEFINITION Tlie discussion has progressed without a formal definition of case studies. Moreover, commonly asked questions about case studies have still been unanswered. For example, is it still a case study when more than one case is included in the same study? Do case studies preclude the use of quantitative evidence? Can case studies be used to do evaluations? Can case studies include journalistic accounts? Let us now attempt to define the case study strategy and answer these questions. Definition of the Case Study as a Research Strategy The most frequently encountered definitions of case studies have merely repeated the types of topics to which case studies have been applied. For example, in the words of one observer, 12 CASE STUDY RESEARCH the essence of a case study, the central tendency among all types of case study, is that it tries to illuminate a decision or set of decisions: why they were taken, how they were implemented, and with what result (Schramm, 1971, emphasis added) This definition thus cites the topic of "decisions" as the major focus of case studies. Similarly, other topics have been listed, including "individuals," "organizations " "processes," "programs," "neighborhoods," "institutions," and even "events." However, citing the topic is surely insufficient for establishing the needed definition. Alternatively, most social science textbooks have failed to consider the case study a formal research strategy at all (the major exception is the book by five statisticians from Harvard University—Hoaglin et al., 1982). As discussed earlier, one common flaw was to consider the case study as the exploratory stage of some other type of research strategy, and the case study itself was only mentioned in a line or two of text. Another common flaw has been to confuse case studies with ethnographies (Fetterman, 1989) or with participant-observation (Jorgensen, 1989), so that a textbook's presumed discussion of case studies was in reality a description either of the ethnographic method or of participant-observation as a data collection technique. The most popular contemporary texts (e.g., Kidder & Judd, 1986; Nachmias & Nachmias, 1992), in fact, still cover 'field-work" only as a data collection technique and omit any further discussion of case studies. In a historical overview of the case study in American methodological thought, Jennifer Piatt (1992a) explains the reasons for these treatments. She traces the practice of doing case studies back to the conduct of life histories, the work of the Chicago school of sociology, and casework in social work. She then shows how "participant-observation" emerged as a data collection technique, leaving the further definition of any distinctive case study strategy in suspension. Finally, she explains how the first edition of this book (1984) definitively dissociated the case study strategy from the limited perspective of doing participant-observation (or any type of fieldwork). The case study strategy, in her words, begins with "a logic of design ... a strategy to be preferred when circumstances and research problems are appropriate rather than an ideological commitment to be followed whatever the circumstances" (Hatt, 1992a, p. 46). And just what is this logic of design? The technically critical features had been worked out prior to the first edition of this book (Yin, 1981a, 1981b) but now may be restated in two ways. First, the technical definition begins with the scope of a case study: INTRODUCTION 13 1. A case study is an empirical inquiry that • investigates a contemporary phenomenon within its real-fife context, especially when • the boundaries between phenomenon and context are not clearly evident. In other words, you would use the case study method because you deliberately wanted to cover contextual conditions—believing that they might be highly pertinent to your phenomenon of study. Hiis first part of our logic of design therefore helps us to understand case studies by continuing to distinguish them from the other research strategies that have been discussed. An experiment, for instance, deliberately divorces a phenomenon from its context, so that attention can be focused on only a few variables (typically, the context is "controlled" by the laboratory environment), A history, by comparison, does deal with the entangled situation between phenomenon and context, but usually with noncontemporary events. Finally, surveys can try to deal with phenomenon and context, but their ability to investigate the context is extremely limited. The survey designer, for instance, constantly struggles to limit the number of variables to be analyzed (and hence the number of questions that can be asked) to fall safely within the number of respondents that can be surveyed. Second, because phenomenon and context are not always distinguishable in real-life situations, a whole set of other technical characteristics, including data collection and data analysis strategies, now become the second part of our technical definition: 2. The case study inquiry • copes with the technically distinctive situation in which there will be many more variables of interest than data points, and as one result • relies on multiple sources of evidence, with data needing to converge in a triangulating fashion, and as another result • benefits from the prior development of theoretical propositions to guide data collection and analysis. In other words, the case study as a research strategy comprises an all-encompassing method—with the logic of design incorporating specific approaches to data collection and to data analysis. In this sense, the case study is not either a data collection tactic or merely a design feature alone (Stoecker, 1991) but a comprehensive research strategy.1 How the strategy is defined and implemented is the topic of this entire book. 14 CASE STUDY RESEARCH Certain other features of the case study strategy are not critical for defining the strategy but may be considered variations within case study research and also provide answers to common questions. Variations Within Case Studies as a Research Strategy Yes, case study research can include both single- and multiple-case studies. Though some fields, such as political science and public administration, have tried to delineate sharply between these two approaches (and have used such terms as the comparative case method as a distinctive form of multiple-case studies; see Agranoff & Radin, 1991; George, 1979; Lijphart, 1975), single-and multiple-case studies are in reality but two variants of case study designs (see Chapter 2 for more). And, yes, case studies can include, and even be limited to, quantitative evidence. In fact, the contrast between quantitative and qualitative evidence does not distinguish the various research strategies. Note that, as analogous examples, some experiments (such as studies of psychophysical perceptions) and some survey questions (such as those seeking categorical rather than numerical responses) rely on qualitative, and not quantitative, evidence. Likewise, historical research can include enormous amounts of quantitative evidence. As a related but important note, the case study strategy should not be confused with "qualitative research" (see Schwartz & Jacobs, 1979; Strauss &Corbin, 1990; VanMaanen, 1988; Van Maanen, Dabbs, & Faulkner, 1982). Some qualitative research follows ethnographic methods and seeks to satisfy two conditions: (a) the use of close-up, detailed observation of the natural world by the investigator and (b) the attempt to avoid prior commitment to any theoretical model (Jacob, 1987, 1989; Lincoln & Guba, 1986; Stake, 1983; Van Maanen et al„ 1982, p. 16). However, ethnographic research does not always produce case studies (for example, see the brief ethnographies in G. Jacobs, 1970), nor are case studies limited to these two conditions. Instead, case studies can be based on any mix of quantitative and qualitative evidence. In addition, case studies need not always include direct, detailed observations as a source of evidence. As a further note, some investigators distinguish between quantitative research and qualitative research—not on the basis of the type of evidence but on the basis of wholly different philosophical beliefs (e.g., Guba & Lincoln, 1989; Lincoln, 1991; Sechrest, 1991; Smith & Heshusius, 1986). These distinctions have produced a sharp debate within the field of evaluation research. Although some believe that these philosophical beliefs are irrecon- INTRODUCTION 15 cilable, the counterargument can still be posed—that regardless of whether one favors qualitative or quantitative research, there is a strong and essential common ground between the two (Yin, 1994). And, yes, case studies have a distinctive place in evaluation research (see Cronbach et aL, 1980; Guba & Lincoln, 1981; Patton, 1980; U.S. General Accounting Office, 1990; Yin, 1993, chap. 4). There are at least five different applications. The most important is to explain the causal links in real-life interventions that are too complex for the survey or experimental strategies. In evaluation language, the explanations would link program implementation with program effects (U.S. General Accounting Office, 1990). A second application is to describe an intervention and the real-life context in which it occurred. Third, case studies can illustrate certain topics within an evaluation, again in a descriptive mode—even from a journalistic perspective. Fourth, the case study strategy may be used to explore those situations in which the intervention being evaluated has no clear, single set of outcomes. Fifth, the case study may be a "meta-evaluation"—a study of an evaluation study (N. Smith, 1990; Stake, 1986). Whatever the application, one constant theme is that program sponsors—rather than research investigators alone—may have the prominent role in defining the evaluation questions and relevant data categories (U.S. General Accounting Office, 1990). And, finally, yes, certain journalistic efforts can qualify as case studies. Actually, one of the best written and most interesting case studies is about the Watergate scandal, by two reporters from The Washington Post (see BOX 3). SUMMARY This chapter has introduced the importance of the case study as a research strategy. The case study, like other research strategies, is a way of investigating an empirical topic by following a set of prespecified procedures. These procedures will largely dominate the remainder of this book. The chapter also has attempted to distinguish thecase study from alternative research strategies in social science, indicating the situations in which doing a single- or multiple-case study may be preferred, for instance, to doing a survey. Some situations may have no clearly preferred strategy, as the strengths and weaknesses of the various strategies may overlap. The basic approach, however, is to consider all the strategies in a pluralistic fashion—as part of a repertoire for doing social science research from which the investigator may draw according to a given situation. 16 CASE STUDY RESEARCH BOX 3 A Journalistic Case Study Although public memory of President Richard M. Nixon's resignation has receded, Bernstein and Woodward's All the President's Men (1974) remains a fascinating account of the Watergate scandal. The book is dramatic and suspenses, relies on solid journalistic methods, and serendipitously represents a common design for case studies. The "case," in this book, is not the Watergate burglary itself, or even the Nixon administration more generally. Rather, the case is the "coverup," a complex set of events that occurred in the aftermath of the burglary. Bernstein and Woodward continually confront the reader with two "how" and "why" questions: How did the coverup occur, and why did it occur? Neither is answered easily, and the book's appeal lies in its piecing together of fact after fact, each piece adding up curiously and then potently to an explanation for the coverup. Establishing the how and why of a complex human situation is a classic example of the use of case studies, whether done by journalists or social scientists. If the case involves a significant public event and an appealing explanation, the ingredients may add up, as in All the President's Men, to a best-seller. Finally, the chapter has discussed some of the major criticisms of case study research and has suggested that these criticisms are misdirected. However, we must all work hard to overcome the problems of doing case study research, including the recognition that some of us were not meant, by skill or disposition, to do such research in the first place. Case study research is remarkably hard, even though case studies have traditionally been considered to be "soft4* research. Paradoxically, the "softer" a research strategy, the harder it is to do. EXERCISES 1, Defining a case study question. Develop a question that would be the rationale for a case study you might conduct. Instead of doing a case study, now imagine that you could only do a history, a survey, or an experiment (but not a case study) in order to answer this question. What aspects of the question, if any, could not be answered through these other research strategies? What would be the distinctive advantage of doing a case study to answer this question? 2. Defining, "significant" case study questions. Name a topic you think is worthy of making the subject of a case study. Identify the three major questions your case INTRODUCTION 17 study would try to answer. Now assume that you were actually able to answer these questions with sufficient evidence (i.e., that you had successfully conducted your case study). How would you justify, to a colleague, the significance of your findings? Would you have advanced some major theory? Would you have discovered something rare? (If you are unimpressed by your answers, perhaps you should consider redefining the major questions of your case.) 3. Identifying "significant" questions in other research strategies. Locate a research study based solely on the use of survey, historical, or experimental (but not case study) methods. Describe the ways in which the findings of this study are significant. Does it advance some major theory? Has it discovered something rare? 4. Examining case studies used for teaching purposes: Obtain a copy of a case study designed for teaching purposes (e.g,v a case in a textbook used in a business school course). Identify the specific ways in which this type of ''teaching" case is different than research case studies. Does the teaching case cite primary documents, contain evidence, or display data? Does the teaching case have a conclusion? What appears to be the main objective of the teaching case? 5. Defining different types of case studies used for research purposes. Define the three types of case studies used for research (but not teaching) purposes: (a) explanatory or causal case studies, (b) descriptive case studies, and (c) exploratory case studies. Compare the situations in which these different types of case studies would be most applicable, and then name a case study you would like to conduct. Would it be explanatory, descriptive, or exploratory? Why? NOTE 1. Robert Stake (1994) has yet another approach for defining case studies. He considers them not to be "a methodological choice but a choice of object to be studied." Further, the object must be a "functioning specific" (such as a person or classroom) but not a generality (such as a policy). This definition is too broad. Every study of entities qualifying as objects (e.g., people, organizations, and countries) would then be a case study, regardless of the methodology used (e.g., psychological experiment, management survey, economic analysis). Designing Case Studies A research design is the logic that links the data to be collected (and the conclusions to be drawn) to the initial questions of a study. Every empirical study has an implicit, if not explicit, research design. For case studies, four major types of designs are relevant, following a 2 x 2 matrix. The first pair of categories consists of single-case and multiple-case designs. The second pair, which can occur in combination with either of the first pair, is based on the unit or units of analysis to be covered—and distinguishes between holistic and embedded designs. The case study investigator also must maximize four aspects of the quality of any design: (a) construct validity, (b) internal validity (for explanatory or causal case studies only), (c) external validity, and (d) reliability. How the investigator should deal with these four aspects of quality control is summarized in Chapter 2 but also is a major theme throughout the remainder of the book. GENERAL APPROACH TO DESIGNING CASE STUDIES In identifying the research strategy for your research project, Chapter 1 has shown when you should select the case study strategy, as opposed to other strategies. The next task is to design your case study. For this purpose, as in designing any other type of research investigation, a plan, or research design, is needed. The development of this research design is a difficult part of doing case studies. Unlike other research strategies, a comprehensive "catalog" of research designs for case studies has yet to be developed. There are no textbooks like those in the biological and psychological sciences, covering such design considerations as the assignment of subjects to different "groups," the selection of different stimuli or experimental conditions, or the identification of various response measures (see Cochran & Cox, 1957; Fisher, 1935, cited in Cochran & Cox, 1957; Sidowski, 1966). In a laboratory experiment, each of these choices reflects an important logical connection to the issues being studied. Similarly, there are not even textbooks like the well-known volumes 18 DESIGNING CASE STUDIES 19 by Campbell and Stanley (1966) or by Cook and Campbell (1979), which summarize the various research designs for quasi-experimental situations. Nor have there emerged any common designs—for example, "panel" studies—such as those now recognized in doing survey research (see Kidder & Judd, 1986, chap. 6). One pitfall to be avoided, however, is to consider case study designs to be a subset or variant of the research designs used for other strategies, such as experiments. For the longest time, scholars incorrectly thought that the case study was but one type of quasi-experimental design (the one-shot posttest-only design). This misperception has Finally been corrected, with the following statement appearing in a revision on quasi-experimental designs: "Certainly the case study as normally practiced should not be demeaned by identification with the one-group post-test-only design" (Cook & Campbell, 1979, p. 96). In other words, the one-shot, posttest-only design as a quasi-experimental design still may be considered flawed, but the case study has now been recognized as something different. In fact, the case study is a separate research strategy that has its own research designs. Unfortunately, case study research designs have not been codified. The following chapter therefore expands on the new methodological ground broken by the fust edition of this book and describes a basic set of research designs for doing single- and multiple-case studies. Although these designs will need to be continually modified and improved in the future, in their present form they will nevertheless help you to design more rigorous and methodologically sound case studies. Definition of Research Designs Every type of empirical research has an implicit, if not explicit, research design. In the most elementary sense, the design is the logical sequence that connects the empirical data to a study's initial research questions and, ultimately, to its conclusions. Colloquially, a research design is an action plan for getting from here to there> where here may be defined as the initial set of questions to be answered, and there is some set of conclusions (answers) about these questions. Between "here" and "there" may be found a number of major steps, including the collection and analysis of relevant data. As a summary definition, another textbook has described a research design as a plan that guides the investigator in the process of collecting, analyzing, and interpreting observations. It is a logical model of proof that allows the researcher to draw 20 CASE STUDY RESEARCH inferences concerning causal relations among the variables under investigation. The research design also defines the domain of generalizability, that is, whether the obtained interpretations can be generalized to a larger population or to different situations. (Nachmias & Nachmias, 1992, pp. 77-78, emphasis added) Another way of thinking about a research design is as a "blueprint" of research, dealing with at least four problems: what questions to study, what data are relevant, what data to collect, and how to analyze the results (see F. Borum, personal communication, Copenhagen Business School, Copenhagen, Denmark, 1991; Philliber, Schwab, & Samsloss, 1980). Note that a research design is much more than a work plan. The main purpose of the design is to help to avoid the situation in which the evidence does not address the initial research questions. In this sense, a research design deals with a logical problem and not a logistical problem. As a simple example, suppose you want to study a single organization. Your research questions, however, have to do with the organization's relationships with other organizations—their competitive or collaborative nature, for example. S uch questions can be answered only if you collect information directly from the other organizations and not merely from the one you started with. If you complete your study by examining only one organization, you cannot draw accurate conclusions about interorganizational partnerships. This is a flaw in your research design, not in your work plan. The outcome could have been avoided if you had developed an appropri ate research design in the first place. Components of Research Designs For case studies, five components of a research design are especially important: 1. a study's questions, 2. its propositions, if any, 3. its unit(s) of analysis, 4. the logic linking the data to the propositions, and 5. the criteria for interpreting the findings. Study questions. This first component has already been described in Chapter 1. Although the substance of your questions will vary, Chapter 1 suggested that the form of the question—in terms of "who," "what," "where," "how," and "why"—provides an important clue regarding the most relevant research strategy to be used. The case study strategy is most likely to DESIGNING CASE STUDIES 21 be appropriate for "how" and "why" questions, so your initial task is to clarify precisely the nature of your study questions in this regard. Study propositions. As for the second component, each proposition directs attention to something that should be examined within the scope of the study. For instance, assume that your research, on the topic of interorganiza-tional partnerships, began with the question; How and why do organizations collaborate with one another to provide joint services (for example, a manufacturer and a retail store collaborating to sell certain computer products)? These "how" and "why** questions, capturing what you are really interested in answering, led you to the case study as the appropriate strategy in the first place. Nevertheless, these "how" and "why*' questions do not point to what you should study. Only if you are forced to state some propositions will you move in the right direction. For instance, you might think that organizations collaborate because they derive mutual benefits. This proposition, in addition to reflecting an important theoretical issue (that other incentives for collaboration do not exist or are unimportant), also begins to tell you where to look for relevant evidence (to define and ascertain the extent of specific benefits to each organization). At the same time, some studies may have a legitimate reason for not having any propositions. This is the condition—which exists in experiments, surveys, and the other research strategies alike—in which a topic is the subject of "exploration/* Every exploration, however, should still have some purpose-Instead of stating propositions, the design for an exploratory study should state a purpose, as well as the criteria by which an exploration will be judged successful. Consider the analogy in BOX 4 for exploratory case studies. Can you imagine how you would ask for support from Queen Isabella to do your exploratory study? Unit of analysis. This third component is related to the fundamental problem of defining what the "case" is—a problem that has plagued many investigators at the outset of case studies. For instance, in the classic case study, a "case" may be an individual. Jennifer Piatt (1992a, 1992b) has noted how the early case studies in the Chicago school of sociology were life histories of such roles as juvenile delinquents or derelict men. You also can imagine case studies of clinical patients, of exemplary students, or of certain types of leaders. In each situation, an individual person is the case being studied, and the individual is the primary unit of analysis. Information about each relevant individual would be collected, and several such individuals or "cases" might be included in a multiple-case study. Propositions would still be needed to help identify the relevant information about this individual or 22 CASE STUDY RESEARCH BOX 4 "Exploration" as an Analogy for an Exploratory Case Study When Christopher Columbus went to Queen Isabella to ask for support for his "exploration" of the New Woridt he had to have some reasons for asking for three ships (Why not one? Why not five?), and he had some rationale for going westward (Why not south? Why not south and then east?). He also had some (mistaken) criteria for recognizing the Indies when he actually encountered them. In short, his exploration began with some rationale and direction, even if his initial assumptions might later have been proved wrong (Wilford, 1992). This same degree of rationale and direction should underlie even an exploratory case study. individuals. Without such propositions, an investigator might be tempted to collect "everything," which is impossible to do. For example, the propositions in studying these individuals might involve the influence of early childhood or the role of peer relationships. Such topics already represent a vast narrowing of the relevant data. The more a study contains specific propositions, the more it will stay within feasible limits. Of course, the "case" also can be some event or entity that is less well defined than a single individual. Case studies have been done about decisions, about programs, about the implementation process, and about organizational change. Feagin, Orum, & Sjoberg (1991) contains some classic examples of these single cases in sociology and political science. Beware of these types of topics—none is easily defined in terms of the beginning or end points of the "case." For example, a case study of a specific program may reveal (a) variations in program definition, depending upon the perspective of different actors, and (b) program components that existed prior to the formal designation of the program. Any case study of such a program would therefore have to confront these conditions in delineating the unit of analysis. As a general guide, the definition of the unit of analysis (and therefore of the case) is related to the way the initial research questions have been defined. Suppose, for example, you want to study the role of the United States in the world economy, Peter Dmcker (19$6) has writt&n a provocative essay about fundamental changes in the world economy, including the importance of "capital movements" independent of the flow of goods and services. The unit of analysis for your'case study might be a country's economy, an industry in DESIGNING CASE STUDIES 23 BOX 5a What Is the Unit of Analysis? The Sold of a New Machine (1981) was a Pulitzer prize-winning book by Tracy Kidder. The book, also a best-seller, is about the development of a new minicomputer produced by Data General Corporation, intended to compete directly with one produced by Digital Equipment Corporation. This easy-to-read book describes how Data General's engineering team invented and developed the new computer. The book begins with the initial conceptualization of the computer and ends when the engineering team relinquishes control of the machine to Data General's marketing staff. The book is an excellent example of a case study. However, the book also illustrates a fundamental problem in doing case studies—that of defining the unit of analysis. Is the case study about the minicomputer, or is it about the dynamics of a small group—die engineering team? The answer is critical if we want to understand how the case study relates to a broader body of knowledge—that is, whether to geneialize to a technology topic or to a group dynamics topic. Because the book is not an academic study, it does not need to, nor does it, provide an answer. the world marketplace, an economic policy, or the trade or capital flow between two countries. Each unit of analysis would call for a slightly different research design and data collection strategy. Selection of the appropriate unit of analysis results from your accurately specifying the primary research questions. If your questions do not lead to the favoring of one unit of analysis over another, your questions are probably either too vague or too numerous— and you may have trouble conducting your case study. Sometimes, the unit of analysis may have been defined one way, even though the phenomenon being studied calls for a different definition. Most frequently, investigators have confused case studies of neighborhoods with case studies of small groups (for another example, confusing an innovation with a small group in organizational studies, see BOX 5a). How a general area such as a neighborhood copes with racial transition, upgrading, and other phenomena can be quite different than how a small group copes with these same phenomena. Street Corner Society (Whyte, 1943/1955—also see BOX 1 in Chapter 1 of this book) and Tally's Corner (Liebow, 1967—also see BOX 9, this chapter), for instance, have often been mistaken for being case studies of neighborhoods when in fact they are case studies of small groups (note that in neither book is the neighborhood geography described, even though 24 CASE STUDY RESEARCH BOX 5b A Clearer Choice Among Units of Analysis Ira Magaziner and Mark Patinkin's book The Silent War: Inside the Global Business Battles Shaping America's Future (1989) presents nine case studies. Each case study helps the reader to understand a real-life situation of international economic competition. Two of the cases appear similar but in fact have different main units of analysis. One case, about the Korean firm Samsung, is a case study of the critical policies that make the firm competitive. Understanding Korean economic development is part of the context, and the case study also contains an embedded unit—Samsung's development of the microwave oven as an illustrative product The other case, about the development of an Apple computer factory in Singapore, is in fact a case study of Singapore's critical policies mat make the country competitive- The Apple computer factory experiences—an embedded unit of analysis—is actually an illustrative example of how national policies affect foreign investments. These two cases show how the definition of the main and embedded units of analyses, as well as the definition of the contextual events surrounding these unitsi depends on the level of inquiry. The main unit of analysis is likely to be at the level being addressed by the main study questions. the small groups lived in a small area with clear neighborhood implications). BOX 5b, however, presents a good example of how units of analyses can be defined in a more discriminating manner—in the field of world trade. Most investigators will encounter this type of confusion in defining the unit of analysis. To reduce the confusion, one good practice is to discuss the potential case with a colleague. Try to explain to that person what questions you are trying to answer and why you have chosen a specific case or group of cases as a way of answering those questions. This may help you to avoid incorrectly identifying the unit of analysis. Once the general definition of the case has been established, other clarifications in the unit of analysis become important. If the unit of analysis is a small group, for instance, the persons to be included within the group (the immediate topic of the case study) must be distinguished from those who are outside it (the context for the case study). Similarly, if the case is about services in a specific geographic area, decisions need to be made about public services whose district boundaries do not coincide with the area. Finally, for almost any topic that might be chosen, specific time boundaries are needed to define the beginning and end of the case. All of these types of questions need to be DESIGNING CASE STUDIES 25 considered and answered to define the unit of analysis and thereby to determine the limits of the data collection and analysis. One final point needs to be made about defining the case and the unit of analysis, pertaining to the role of the available research literature. Most researchers will want to compare their findings with previous research; for this reason, the key definitions should not be idiosyncratic. Rather, each case study and unit of analysis either should be similar to those previously studied by others or should deviate in clear, operationally defined ways. In this manner, the previous literature therefore also can become a guide for defining the case and unit of analysis. Unking data to propositions, and criteria for interpreting the findings. The fourth and fifth components have been the least well developed in case studies. These components represent the data analysis steps in case study research, and a research design should lay the foundations for this analysis. Linking data to propositions can be done any number of ways, but none has become as precisely defined as the assignment of subjects and treatment conditions in psychological experiments (which is the way that hypotheses and data are connected in psychology). One promising approach for case studies is the idea of "pattern-matching" described by Donald Campbell (1975), whereby several pieces of information from the same case may be related to some theoretical proposition. In a related article on one type of pattern—a time-series pattern—Campbell (1969) illustrated this approach but without labeling it as such. In his article, Campbell first showed how the annual number of traffic fatalities in Connecticut had seemed to decline after the passage of a new state law limiting the speed to 55 miles per hour. However, further examination of the fatality rate, over a number of years before and after the legal change, showed unsystematic fluctuation rather than any marked reduction. A simple eyeball test was all that was needed to show that the actual pattern looked unsystematic rather than following a downtrend (see Figure 2.1), and thus Campbell concluded that the speed limit had had no effect on the number of traffic fatalities. What Campbell did was describe two potential patterns and then show that the data matched one better than the other. If the two potential patterns are considered rival propositions (an "effects" proposition and a "no effects" proposition, regarding the impact of the new speed limit law), the pattern-matching technique is a way of relating the data to the propositions, even though the entire study consists of only a singlecase(the state of Connecticut). This article also illustrates the problems in dealing with the fifth component, the criteria for interpreting a study's findings, Campbell's data matched 26 CASE STUDY RESEARCH a priori propositions t an "effect*" pattern number of fataJittea 1] ■ * ■ * ■ 1114 1(1 TEARS actual observationsi (Campbell, 1969) 325 900 of falalitte* **° 22» (- 200 a "no effect*" pattern 1 2 3 4 5 0 7 TEARS '51 '82 TS3 »84 'BS 'M '87 'SS 'S» TEARS *.. a "no effect**' pattern Figure 2.1. An Example of Pattern-Matching SOURCE: COSMOS Corporation. one pattern much better than they matched the other. But how close does a match have to be so as to be considered a match? Note that Campbell did not do any statistical test to make the comparison. Nor would a statistical test have been possible, because each data point in the pattern was a single number—the number of fatalities for that year—for which one could not calculate a variance and could not conduct any statistical test. Currently, there is no precise way of setting the criteria for interpreting these types of findings.. One hopes that the different patterns are sufficiently contrasting that (as in Campbell's case) the findings can be interpreted in terms of comparing at least two rival propositions. Summary. A research design should include five components. Although the current state of the art does not provide detailed guidance on the last two, the complete research design should not only indicate what data are to be collected—as indicated by (a) a study's questions, (b) its propositions, and (c) its units of analysis. The design also should tell you what is to be done after the data have been collected—as indicated by (d) the logic DESIGNING CASE STUDIES 27 linking the data to the propositions and (e) the criteria for interpreting the findings. The Role of Theory in Design Work Covering these preceding five components of research designs will effectively force you to begin constructing a preliminary theory related to your topic of study. This role of theory development prior to the conduct of any data collection, is one point of difference between case studies and related methods such as ethnography (Lincoln & Guba, 1985, 1986; Van Maanen, 1988; Van Maanen et al, 1982) and "grounded theory" (Strauss & Corbin, 1990), Typically, these related methods deliberately avoid specifying any theoretical propositions at the outset of an inquiry. As a result, students wrongly think that by using the case study method, they can proceed quickly into the data collection phase of their work, and they have been encouraged to make their "field contacts" as quickly as possible. No guidance could be more misleading. Among other considerations, the relevant field contacts depend upon an understanding—or theory—of what is being studied. Theory development. For case studies, theory development as part of the design phase is essential, whether the ensuing case study's purpose is to develop or to test theory. Using a case study on the implementation of a new management information system (MIS) as an example (Markus, 1983), the simplest ingredient of a theory is a statement such as the following: The case study will show why implementation only succeeded when the organization was able to re-structure itself, and not just overlay the new MIS on the old organizational structure. (Markus, 1983) The statement presents the nutshell of a theory of MIS implementation— that is, that organizational restructuring is needed to make MIS implementation work. Using the same case, an additional ingredient might be the following statement: The case study will also show why the simple replacement of key persons was not sufficient for successful implementation. (Markus, 1983) This second statement presents the nutshell of a theory—that is, that MIS implementation fails because of the resistance to change on the part of 28 CASE STUDY RESEARCH individual people, and (hat the replacement of such people is the only requirement for implementation to succeed. You can see that, as these two initial ingredients are elaborated, the stated ideas will increasingly cover the questions, propositions, units of analysis, logic connecting data to propositions, and criteria for interpreting the findings—that is, the five components of the needed research design. In this sense, the complete research design embodies a ''theory** of what is being studied. This theory should by no means be considered with the formality of grand theory in social science, nor are you being asked to be a masterful theoretician. Rather, the simple goal is to have a sufficient blueprint for your study, and this requires theoretical propositions. Then, the complete research design will provide surprisingly strong guidance in determining what data to collect and the strategies for analyzing the data. For this reason, theory devel opment prior to the collection of any case study data is an essential step in doing case studies. However, theory development takes time and can be difficult (Eisenhardt, 1989). For some topics, existing works may provide a rich theoretical framework for designing a specific case study. If you are interested in international i economic development, for instance, Peter Drucker's "The Changed World Economy" (1986) is an exceptional source of theories and hypotheses. j Omcker claims that the world economy has changed significantly from the j past. He points to the "uncoupling" between the primary products (raw materials) economy and the industrial economy, a similar uncoupling between low labor costs and manufacturing production, and the uncoupling between financial markets and the real economy of goods and services. To test these propositions might require different studies, some focusing on the different uncouplings, others focusing on specific industries, and yet others explaining the plight of specific countries. Each different study would likely call for a different unit of analysis. Drucker's theoretical framework would provide guidance for designing these studies and even for collecting relevant data, j In other situations, the appropriate theory may be a descriptive theory (see j BOX 6, and also BOX 1 for another example), and your concern should focus I on such issues as (a) the purpose of the descriptive effort, (b) the full but 1 realistic range of topics that might be considered a "complete" description of | what is to be studied, and (c) the likely topic(s) that will be the essence of the j description. Good answers to these questions, including the rationales under- i lying the answers, will help you go a long way toward developing the needed \ theoretical base—and research design—for your study. I For yet other topics, the existing knowledge base may be poor, and the ! available literature will provide no conceptual framework or hypotheses of j note. Such a knowledge base does not lend itself to the development of good : DESIGNING CASE STUDIES 29 BOX6 Using a Metaphor to Develop Descriptive Theory Whether four countries—the American colonies, Russia, England, and France—all underwent similar courses of events during their major political revolutions is the topic of Crane Brinton's famous historical study—The Anatomy of a Revotuthn (1938). Tracing and analyzing these events is done in a descriptive manner, as the author's purpose is not so much to explain the revolutions as to tetermine whether they followed similar courses. The "cross-case" analysis reveals major similarities: All societies were on the upgrade, economically,* there were bitter class antagonisms; the intellectuals deserted from positions of leadership; government machinery was inefficient; and the ruling class exhibited immoral, dissolute, or inept behavior (or all three). However, rather than relying solely on this "factors" approach to description, the author also develops the metaphor of a human body suffering from a fever as a way of describing the pattern of events over time. The author adtptly uses the cyclic pattern of fever and chills, rising to a critical point and followed by a false tranquility, to describe the ebb and flow of events in the four revolutions. theoretical statements, and any new empirical study is likely to assume the characteristic of being an "exploratory" study. Nevertheless, as noted earlier with the illustrative case in BOX 4, even an exploratory case study should be preceded by statements about (a) what is to be explored, (b) the purpose of the exploration, and (c) the criteria by which the exploration will be judged successful. Illustrative types of theories. In general, to overcome the barriers to theory development, you should try to prepare for your case study by doing such things as reviewing the literature related to what you would like to study (also see Cooper, 1984); discussing your topic and ideas with colleagues or teachers; and asking yourself challenging questions about what you are studying, why you are proposing to do the study, and what you hope to learn as a result of the study. As a further reminder, you should be aware of the full range of theories that might be relevant to your study. For instance, note that the MIS example illustrates MIS (iimplementation" theory, and that this is but one type of theory that can be the subject of study. Other types of theories for you to consider include the following: 30 CASE STUDY RESEARCH • Individual theories—for example, theories of individual development, cognitive behavior, personality, learning and disability, individual perception, and interpersonal interactions * Group theories—for example, theories of family functioning, informal groups, work teams, supervisory-employee coordination, and interpersonal networks • Organizational theories—for example, theories of bureaucracies, organizational structure and functions, excellence in organizational performance (e.g., Harrison, 1987), and interorganizational partnerships * Societal theories—for example, theories of urban development, international behavior, cultural institutions, technological development, and marketplace functions Other examples cut across some of these illustrative types. Decisionmaking theory (Carroll & Johnson, 1992), for instance, can involve individuals, organizations, or social groups. As another example, a common topic of case studies is the evaluation of publicly supported programs, such as federal, state, or local programs. In this situation, the development of a theory of how a program is supposed to work is essential to the design of the evaluation but has been commonly underemphasized in thepast (Bickman, 1987). According to Bickman, analysts have frequently confused the theory of the program (e.g., how to make education more effective) with the theory of program implementation (e.g., how to install an effective program). Where policymakers want to know the desired substantive steps (e.g., describe a newly effective curriculum), the analysts unfortunately recommend managerial steps (e.g., hire a good project director). This mismatch can be avoided by giving closer attention to the substantive theory. Generalizing from case study to theory. Theory development does not only facilitate the data collection phase of the ensuing case study. The appropriately developed theory also is the level at which the generalization of the case study results will occur. This role of theory has been characterized throughout this book as "analytic generalization" and has been contrasted with another way of generalizing results, known as "statistical generalization." Understanding the distinction between these two types of generalization may be your most important challenge in doing case studies. Let us take the more commonly recognized way of generalizing—"statistical generalization"—first, although it is the less relevant one fordoing case studies. In statistical generalization, an inference is made about a population (or universe) on the basis of empirical data collected about a sample. This is shown as a Level One Inference in Figure 2.2.1 This method of generalizing DESIGNING CASE STUDIES 31 LEVEL TWO r theory policy implication rival theory rtvul policy implfotipn SURVEY ,' rt i I population cft* r»