Case design, case selection, types of case studies

Question 1

Why is it important to select cases purposefully in qualitative research?

Answer 1

1. To avoid selection bias and faulty generalisations
2. Random sampling is often not an option in qualitative research, due to the small number of cases or because it is theoretically not desirable
3. The cases you choose determine the answer you get

Question 2

Case selection on the dependent variable

Answer 2

Can lead to jumping to conclusions that any characteristic that the selected cases share is a cause. It can be useful for the development of new theories or the indentification of plausible causal variables.

Question 3

Types of case study designs

Answer 3

1. Case-centred case studies
2. Theory centered case studies

Question 4

Case-centred case studies

Answer 4

1. The aim is to describe, explain, interpret, and/or understand a single case as an end in itself and not as a way for developing broader theoretical generalisations
2. Should still be theory-guided
3. Mainly uses within-case evidence
4. Usually Y-centred
5. More deterministic way of understanding causal relations
6. Often focuses on rare events

Question 5

Theory centred case studies

Answer 5

1. A case study is theory centred when it contributes to the advancement of a general theory
2. Exploratory/hypothesis generating or modifying case study
3. Confirmatory/hypothesis testing case studies

Question 6

Hypothesis building

Answer 6

No existing theory you build on
1. Formulating concepts
2. Selecting case
3. Exploratory empirical analysis
4. Formulating hypothesis

Question 7

Hypothesis testing

Answer 7

(No) theory to build on
1. Formulating concepts
2. Formulating hypothesis
3. Selecting cases
4. Confirmatory empirical analysis
5. Evaluating hypothesis

Question 8

Theory based case selection strategies

Answer 8

1. Most similar (different outcome) case study design
2. Most different (same outcome) case study design
3. Crucial case study designs
   a. Most likely case study design
   b. Least likely case study design

Question 9

Distribution based case selection strategies

Answer 9

1. Typical case study design
2. Diverse case study design
3. Extreme case study design
4. Deviant case study design (partly theory-based as well)
5. Influential case study design

Question 10

Hypothesis modifying

Answer 10

Theory to build on
1. Formulating concepts
2. Choosing hypothesis for modification
3. Selecting cases
4. Exploratory empirical analysis
5. Refining hypothesis

Question 11

How to choose a case for case study analysis?

Answer 11

1. Useful variation on the dimensions of theoretical interest in X and Y
2. Represenativeness (external validity)
3. There is a theoretical or empirical puzzle

Question 12

Most similar (different outcome) case studies

Answer 12

Look at cases that are most similar on most of the independent variables, but have a different outcome and one different independent variable. This one different independent variable would then be the causal factor.
1. Objective for case selection is variation
2. Selection of at least 2 cases
3. Used to identify and test causal effects between X and Y
4. Identification of most similar cases is done through crosstabulation for small-N studies (two criterias and select cases from that). For large-N studies matching strategies vs. control variable approach.

Question 13

Most different (similar outcome) case study designs

Answer 13

Same outcome with very different cases. The cases differ on everything, except for one independent variable. This is then the factor that makes it so the outcome is the same.
1. Objective for case selection is variation
2. Selection of at least 2 cases
3. Used to identify and test causal effects between X and Y
4. Identification of most similar cases is done through crosstabulation for small-N studies (two criterias and select cases from that). For large-N studies matching strategies vs. control variable approach.

Question 14

Crucial case study designs

Answer 14

Based on most-likely or least-likely study designs. They can be useful for testing theories (exploratory research design).
1. Objective for case selection is (un)representativeness.
2. Based on the assumption that most cases are more important for testing theories than others
3. Best to test hypotheses of the necessary/sufficient condition type
4. Sinatra inference; If I can make it there, I can make it anywhere. Least likely cases would be used to confirm a theory, most likely cases would be used to disconfirm a theory (Reverse Sinatra).
5. Identifying most/least likely cases is based on prior theoretical expectations as how how X and Y should relate, and scope conditions (subset of cases to which theory applies) the original theory states.

Question 15

Typical case study

Answer 15

Focuses on a case that is an example of a stable cross-case relationship.
1. Objective for case selection is representativeness.
2. Puzzle of interest is within-case. It is the identification of causal mechanism, validation of a causal mechanism or disconfirmation of a causal mechanism.
3. Typical cases are identified by a theoretically expected score on X and Y and have a high representativeness of other cases in the population for small-N studies. For large-N studies they are identified by a random selection of cases based on the smallest possible distance between the predicted value and the actually measured value.

Question 16

Diverse case study design

Answer 16

Main goal is to get a maximum variance along different relevant dimensions. Cover the distribution of the pattern out there.
1. Objective for case selection is variation.
2. At least 2 cases needed
3. Can be used for both exploratory and confirmatory research.

Question 17

Extreme case study designs

Answer 17

Extreme case method selects a case because it is an extreme value of the X or Y variable you’re interested in.
1. Objective for case selection is the rareness of the case on X or Y.
2. Aims at maximizing the variance on the dimension of interest between the case and the population/sample.
3. used for exploratory research, mainly generating hypotheses.

Question 18

Deviant case study designs

Answer 18

Deviant cases are cases that show a surprising value.
1. Objective for case selection is atypicality
2. Deviant cases are not representative of the population/sample
3. Goal is to identify factors that make it so this case is deviant. Understand why the theory is wrong for this case.
4. Useful for investigating theoretical anomalies. You can then identify new or modified hypotheses (exploratory research) and disconfirm deterministic propositions.

Question 19

Influential case study designs

Answer 19

Cases that influence overall findings from research. Study them to find out why they influence these studies so much.
1. Objective for case selection is checking theoretical assumptions.
2. If these cases would be excluded from the analysis of the results, the conclusions of the analysis would change.
3. Used to address concerns that the results of a study are driven by one or a few influential cases.