  The speeches stated by influential politicians can have a decisive impact on
the future of a country. In particular, the economic content of such speeches
affects the economy of countries and their financial markets. For this reason,
we examine a novel dataset containing the economic content of 951 speeches
stated by 45 US Presidents from George Washington (April 1789) to Donald Trump
(February 2017). In doing so, we use an economic glossary carried out by means
of text mining techniques. The goal of our study is to examine the structure of
significant interconnections within a network obtained from the economic
content of presidential speeches. In such a network, nodes are represented by
talks and links by values of cosine similarity, the latter computed using the
occurrences of the economic terms in the speeches. The resulting network
displays a peculiar structure made up of a core (i.e. a set of highly central
and densely connected nodes) and a periphery (i.e. a set of non-central and
sparsely connected nodes). The presence of different economic dictionaries
employed by the Presidents characterize the core-periphery structure. The
Presidents' talks belonging to the network's core share the usage of generic
(non-technical) economic locutions like "interest" or "trade". While the use of
more technical and less frequent terms characterizes the periphery (e.g.
"yield" ). Furthermore, the speeches close in time share a common economic
dictionary. These results together with the economics glossary usages during
the US periods of boom and crisis provide unique insights on the economic
content relationships among Presidents' speeches.

General Economics;Computers and Society;Economics