A theory that the behavior of nations to one another is a result of their differences and similarities in attributes has been tested on 1955 data. This paper reports a retest of this theory on 1963 data. The model interprets differences and similarities as implacable forces like gravity and centrifugal force which the nation cannot alter and which affect its behavior regardless of its history, culture, or other unique characteristics. A second model interprets differences and similarities as general forces modified in their impact on behavior by the unique characteristics of each nation. A retest of this model was consistent with previous findings in showing an ability to explain around fifty percent of the variation in international behavior. (Author).

In connection with the development and testing of a field theory of international relations, the 1963 dyadic behavior of nations was analyzed to determine its dimensions. A secondary analysis was also done to determine how well these dimensions could be predicted from those found in a similar analysis of 1955 data. Large shifts are reported in the behavior of dyads between 1955 and 1963. The development of a cooperation-conflict scale for 1955 and 1963 and a plot of selected dyads on it shows that the scale measures the major 1955-1963 shifts in behavior. (Author).

An annual index to the monographs appears early in the following year.

This book is open access under a CC BY license. The book provides a critical and constructive assessment of the many contributions to social science and politics made by Professor R. J. Rummel. Rummel was a prolific writer and an important teacher and mentor to a number of people who in turn have made their mark on the profession. His work has always been controversial. But after the end of the Cold War, his views on genocide and the democratic peace in particular have gained wide recognition in the profession. He was also a pioneer in the use of statistical methods in international relations. His work in not easily classified in the traditional categories of international relations research (realism, idealism, and constructivism). He was by no means a pacifist and his views on the US-Soviet arms race led him to be classified as a hawk. But his work on the democratic peace has become extremely influential among liberal IR scholars and peace researchers. Above all, he was a libertarian.