Conversation is a cornerstone of social connection and is linked to well-being outcomes. Conversations vary widely in type with some portion generating complex, dynamic stories. One approach to studying how conversations unfold in time is through statistical patterns such as Heaps' law, which holds that vocabulary size scales with document length. Little work on Heaps's law has looked at conversation and considered how language features impact scaling. We measure Heaps' law for conversations recorded in two distinct mediums: 1. Strangers brought together on video chat and 2. Fictional characters in movies. We find that scaling of vocabulary size differs by parts of speech. We discuss these findings through behavioral and linguistic frameworks.

翻译：对话是社会联系的基石，并与幸福感结果相关联。对话类型差异显著，其中一部分会生成复杂、动态的故事。研究对话如何随时间展开的一种方法是通过统计模式，例如赫普斯定律，该定律指出词汇量随文档长度呈比例增长。目前针对赫普斯定律在对话中的研究较少，且鲜有探讨语言特征如何影响这种比例关系。我们测量了两种不同媒介中记录的对话的赫普斯定律：1. 通过视频聊天聚集的陌生人对话；2. 电影中虚构人物的对话。我们发现词汇量的比例关系因词性而异。我们通过行为学和语言学框架对这些发现进行了讨论。