In a recent paper published in the Journal of Language Evolution, Kauhanen, Einhaus & Walkden (https://doi.org/10.1093/jole/lzad005, KEW) challenge the results presented in one of my papers (Koplenig, Royal Society Open Science, 6, 181274 (2019), https://doi.org/10.1098/rsos.181274), in which I tried to show through a series of statistical analyses that large numbers of L2 (second language) speakers do not seem to affect the (grammatical or statistical) complexity of a language. To this end, I focus on the way in which the Ethnologue assesses language status: a language is characterised as vehicular if, in addition to being used by L1 (first language) speakers, it should also have a significant number of L2 users. KEW criticise both the use of vehicularity as a (binary) indicator of whether a language has a significant number of L2 users and the idea of imputing a zero proportion of L2 speakers to non-vehicular languages whenever a direct estimate of that proportion is unavailable. While I recognise the importance of post-publication commentary on published research, I show in this rejoinder that both points of criticism are explicitly mentioned and analysed in my paper. In addition, I also comment on other points raised by KEW and demonstrate that both alternative analyses offered by KEW do not stand up to closer scrutiny.

翻译：在近期发表于《语言进化杂志》（Journal of Language Evolution）的一篇论文中，Kauhanen、Einhaus与Walkden（https://doi.org/10.1093/jole/lzad005，简称KEW）对我一篇论文（Koplenig，《皇家学会开放科学》（Royal Society Open Science），6，181274（2019），https://doi.org/10.1098/rsos.181274）中的结果提出了质疑。在该论文中，我试图通过一系列统计分析表明，大量L2（第二语言）使用者似乎并未影响语言的（语法或统计）复杂度。为此，我重点关注Ethnologue对语言状态的评估方式：若一种语言除L1（第一语言）使用外，还有大量L2使用者，则被描述为“工具性语言”（vehicular）。KEW批评了两点：一是将工具性作为衡量语言是否拥有大量L2使用者的（二值）指标，二是在无法直接估计非工具性语言中L2使用者比例时，将其比例默认为零。我承认对已发表研究进行出版后评论的重要性，但在此回应中表明，上述两点批评均已在原文中明确提及并分析。此外，我还对KEW提出的其他论点进行了评论，并论证KEW提供的两种替代分析均经不起更细致的推敲。