This paper deals with a quantitative analysis of the content of official political speeches. We study a set of about one thousand talks pronounced by the US Presidents, ranging from Washington to Trump. In particular, we search for the relevance of the rare words, i.e. those said only once in each speech – the so-called hapaxes. We implement a rank-size procedure of Zipf–Mandelbrot type for discussing the hapaxes’ frequencies regularity over the overall set of speeches. Starting from the obtained rank-size law, we define and detect the core of the hapaxes set by means of a procedure based on an Hirsch index variant. We discuss the resulting list of words in the light of the overall US Presidents’ speeches. We further show that this core of hapaxes itself can be well fitted through a Zipf–Mandelbrot law and that contains elements producing deviations at the low ranks between scatter plots and fitted curve – the so-called king and vice-roy effect. Some socio-political insights are derived from the obtained findings about the US Presidents messages.

本文对官方政治演讲的内容进行定量分析。我们研究了美国总统宣布的一系列大约1000场演讲，涉及华盛顿到特朗普。尤其是，我们搜索稀有单词的相关性，即在每个语音中只说过一次的单词-所谓的hapaxes。我们实现了Zipf–Mandelbrot类型的秩大小过程，用于讨论整个语音集合中hapax的频率规律性。从获得的秩大小定律开始，我们定义并检测hapaxes的核心通过基于Hirsch索引变体的过程进行设置。我们将根据美国总统的总体讲话来讨论最终的词汇表。我们进一步证明，hap谱核心本身可以通过Zipf-Mandelbrot定律很好地拟合，并且包含在散点图和拟合曲线之间的低阶上产生偏差的元素-所谓的国王和副罗伊效应。从有关美国总统信息的发现中可以得出一些社会政治见解。