International relations is generally the study of foreign affairs and international issues among states within a global system. Here, the roles of the states, international agencies, and non-government organizations are analyzed using proper statistical techniques or induction methods. In the past, the study of IR theories was usually limited to geo-political variables (and some economic variables). Today, the approach to studying IR theories is essentially interdisciplinary in orientation and global in application. Total effects of different types of variables are generally taken into consideration.
For example, Wallerstein’s creation of the world system theory was essentially based on two determinant variables: political power of states and economic bargaining power. Wallerstein argued that political power determines the global status of a particular state. Economic bargaining power determines the level of control of a particular state in the world economy. In an interdisciplinary approach, propositions from other legitimate field of subjects are usually taken into account. Academic propositions and hypotheses from other fields are given consideration for their explanatory value.
Interdisciplinary approach to the study of IR theories provides a clear whole figure of global phenomena. In short, by expanding the bases of study, the predictive value of such approach increases. This, essentially, makes a particular IR theory to be self-sufficient and reliable. Does this make ‘understanding’ more complicated? In fact, an interdisciplinary approach to IR makes the whole analysis more simple and flexible. A person reading an IR theory or proposition can easily pinpoint the ‘observed possible causes’ of global events.
In short, while an interdisciplinary approach broadens the analysis, it nevertheless gives a complete picture of a particular event. Hence, IR models become complicated without a possible loss on understanding. Therefore, it is possible to say that the level of abstract complications can result to a narrower form of analysis (wrong functional form). It is also to argue that the best IR models are the ones which take into account the existence of variables. The form first would be thoroughly examined before giving any prediction.