Richard de Neufville's TPP SM Thesis Manual - Title Page - MIT

effectiveness of a design process in two companies will be different. In one itmight be a success, in the other not. Such a contradiction poses a problem.If you had only one case, you might have thought - erroneously - that the designprocess was clearly either successful or not. With two (or more) cases; youcannot tell. To what factor can you ascribe the differences between the results?To differences in the size of the companies? In their location? Mix of products?Management? You need to consider these inevitable questions before you beginyour case studies.When you plan to do several case studies you need to identify the factors thatare most interesting or important. In thinking about a case study of a refinery inIndonesia for example, you would need to decide whether it is most interesting tofocus on refineries, on cultural differences, on the effect of size, etc. This choicedetermines the kind of additional cases you should select.You should choose complementary cases to span the dimension that is importantto you. Thus if you are interested in the effect of size of a company, your casesshould cover the possible range of that factor, from a small company to a largeone.The complementary cases should at the same time be as alike as possible and inthe other dimensions. The reason is that when you observe differences betweenthe results of case studies, you want to minimize the possibility that thesedifferences are caused by secondary factors. So if in your case of an oil refineryin Indonesia you were interested in the effect of size, your complementary casesshould concern differently sized oil companies in Indonesia. You would not wantto look at different sized companies in different countries, because then youwould not know if the differences you observe were due to size or location.In short, your choice of multiple case studies should mimic laboratory researchas closely as practical. You should control for as much as possible whileexamining differences across the factor of interest.Choice of CaseA final word concerns the choice of case. It is a warning.The problem is that many people choose a situation for their case study foremotional or other reasons rather than because of the logic of their thesis. Thischoice is understandable but often has painful consequences for the researchand the thesis.People easily get caught up in a particular case study. They may be natives ofthe country, have worked in a particular company or branch of government, orThesis Definition and Preparation - Richard de Neufville 41