Among the different classifications of research studies, one method is to differentiate them on the basis of the stance that the study takes on the topic. It is very important to clarify to the review committee whether you are trying to prove a point, defend a theory or just explore an idea that was presented by a prior researcher. Based on such treatment of the selected issue, the thesis can be classified as follows:
In this type of research, you have to choose a topic that is present in several literature sources, as you will need to evaluate how others have explored it. It is an exploratory research study wherein you will simply state your views and give comments on what others have said about the issue. While you take a fresh view on the topic and offer an insight, it is not necessary that you contradict others. For example, exploring the problem of food shortage in a specific country and offering your solutions for the same. The introduction in the report must state the thesis question that you will explore.
This is another category of thesis where it is necessary that you defend your point of view. You may need to refute others to prove your theory right. Choosing a topic that has contradictory viewpoints is important; otherwise you will not get any clashing aspects. For example, you may oppose running of certain heavy machinery due to the pollution caused by them. Some writers may be in favor of the topic because of the benefits that accrue from it. This type of report will have a thesis statement.
The introduction of your thesis must clarify which type of research you are conducting and what your readers can expect from the report. Sometimes there may be a very fine line of demarcation between the two types of research and you will have to jot down your thoughts unambiguously to decide which category your report belongs to.