The Credibility of Public and Private Signals: A Document-Based Approach

Crisis bargaining literature has predominantly used formal and qualitative methods to debate the relative efficacy of actions, public words, and private words. These approaches have overlooked the reality that policymakers are bombarded with information and struggle to adduce actual signals from endless noise. Material actions are therefore more effective than any diplomatic communication in shaping elites’ perceptions. Moreover, while ostensibly “costless,” private messages provide a more precise communication channel than public and “costly” pronouncements. Over 18,000 declassified documents from the Berlin Crisis of 1958–63 reflecting private statements, public statements, and White House evaluations of Soviet resolve are digitized and processed using statistical learning techniques to assess these claims. The results indicate that material actions have greater influence on the White House than either public or private statements; that public statements are noisier than private statements; and that private statements have a larger effect on evaluations of resolve than public statements.