Research Methodology in Marketing

This chapter provides a brief characterization of science. This is clarified by considerations on the demarcation between real science and “pseudo-science”. The chapter outlines some criteria for the application of empirical research methods to scientific problems. A somewhat more differentiated presentation follows, in Sect. 1.2, on aspects of the process of scientific knowledge generation (with particular attention to empirical research), and thereafter Sect. 1.3 provides a brief overview of the remaining contents of this book.

Scientific findings are systematized and summarized mainly by theories. Theories are thus the basis for innumerable practical applications and serve to preserve and communicate knowledge as well as to develop understanding. This constitutes their central importance for all scientific disciplines. The first section describes what a theory is. This is then illustrated by the example of the Elaboration Likelihood Model, a well-known theoretical model in consumer and communication research. Typically, theories serve to help in the understanding of certain aspects of reality. Therefore, the relationship between theory and reality is discussed later (Sect. 2.2). Essential applications of theories (➔ “Relevance of theories”) refer to explanations of real phenomena and the establishment of scientific laws (see Sect. 2.3), the prognosis of events and developments, and the use of such findings for (practical) applications in reality, for example the development of strategies and decisions (see Sect. 2.4). The end of this chapter (Sect. 2.5) presents some typical scientific conclusions (induction, deduction and abduction). In all of these considerations, theories used in different areas of marketing research are the focus of attention.

Assessments of research methods and recommendations for scientific work obviously depend on assumptions about the chances and limits of scientific knowledge, as well as on the aims and conditions of scientific research. In the course of the history of science and the development of marketing research, there have been various views on the philosophy of science, which cannot all be presented and discussed here at length. The authors of this book refer to the view of scientific realism. This position takes into account important experiences from the history of science that correspond well with today’s research practice, and is probably the dominant view today. Some references to earlier approaches in marketing (critical rationalism, relativism) follow, to illustrate the specific features of scientific realism. This chapter also includes the critical reflection of several important aspects of scientific realism (underdetermination of theories, pessimistic induction, context and knowledge) in the second part (Sect. 3.2) of this chapter.

For a long time, the theory building process was not part of philosophy of science considerations, because of the assumption that it was primarily about systematic, barely accessible creative and psychological processes (see Sect. 4.2). Nowadays, this area is still less developed than other parts of epistemology. Nonetheless, Sect. 4.3 presents three common ways of building theories. The building blocks of each theory are concepts with corresponding definitions, which are explained in Sect. 4.1.

This chapter deals with the means to evaluate theories and to (preliminarily) accept or reject them. For this purpose, the different criteria that are used are briefly presented in Sect. 5.1. The chapter mainly focuses on different aspects of empirical tests of a theory. The “classical” path of forming and testing of theory-based hypotheses is presented in Sect. 5.2. A more comprehensive approach to theory testing is the inductive-realistic model that is the subject of Sect. 5.3.

Testing theories requires appropriate methods. First, the concepts of a theory must be made measurable; that is, they have to be operationalized (➔ operationalization) before they can measure corresponding parts of reality (➔ measurement). Only if the transfer of a theory’s elements into measurable variables succeeds are the results of a study meaningful. The main criteria for the quality of measuring instruments in empirical research are validity and reliability. Several established procedures exist to verify these criteria. Important for the suitability of measuring instruments for theory testing is their generalizability and transferability to different contexts, objects, etc. Suitable measuring instruments help to collect data for theory testing. In addition, sampling also plays an important role in the quality of data and, thus, in theory testing (➔ data collection).

Based on hypotheses, theories can be examined empirically (see Sect. 5.2). This chapter illustrates the nature of hypotheses and the procedure for testing them empirically. The chapter specifically addresses the increasingly important relationship between significance tests and effect sizes in research, as well as the problem of post hoc hypothesis tests. Modeling can test several hypotheses simultaneously, by working empirically with regression analyses or with structural equation models.

The investigation of causal relationships is of central concern to science. The proof of causality requires a number of typical features and conditions. There are different types of causal relationships, in particular direct, indirect, and moderated causal relationships. The investigation of causal relationships is typically carried out in the context of experiments. With experimental designs, it is possible to meet the conditions to prove causality. The quality criteria for the evaluation of experimental designs are internal validity and external validity. In certain situations, where the essential principles of experimental investigations do apply, but not all corresponding requirements are met, one speaks of quasi-experiments. Another method for investigating complex causalities is Qualitative Comparative Analysis.

An essential element of scientific realism is the frequent and long-term corroboration of statements based on empirical tests. From an empirical perspective, it is about the question of generalizability, and to what extent empirical findings on the same statement found in various other studies are confirmed. The current chapter deals with approaches in which different results are summarized for the same research topic (meta-analyses: Sect. 9.3) or new investigations are conducted to check previous results (replication studies; Sect. 9.2).

From time to time, scandals triggered by the unethical behavior of scientists (e.g. plagiarism or falsification of data) generate significant notoriety, even grabbing the attention of the public at large. Often associated with this is the deterioration of trust in science. The scientists who are responsible for the scandals typically suffer from severe consequences, such as the retirement of academic degrees or the end of their professional careers.

This chapter first outlines principles and relevance of research ethics. Even negligence and minor inaccuracies in the research process can be ethically problematic, as they impair the accuracy of research results, with potentially significant consequences for further research and application. Therefore, the second part of this chapter presents and discusses several problems that frequently occur in empirical research.