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' 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，并与福祉结果相关联。对话类型差异显著，其中部分对话会产生复杂且动态的叙事。研究对话随时间展开的一种方法是通过统计模式，如赫普定律（Heaps' law），该定律指出词汇量随文本长度呈比例增长。现有研究鲜少将赫普定律应用于对话分析，亦未深入探讨语言特征如何影响其标度行为。本研究测量了两种不同媒介中记录的对话的赫普定律：1. 通过视频聊天聚集的陌生人对话；2. 电影中虚构角色的对话。我们发现词汇量的标度行为因词性而异，并基于行为学与语言学框架对这些发现进行了讨论。