Linguistic positivity in American English: A large-scale diachronic study over the past two centuriesLinguistic positivity in American English: A large-scale diachronic study over the past two centuries

Abstract: This study examines the shifts in linguistic positivity in general American English from the 1820s to the 2000s using a 430-million-token structured historical corpus. Furthermore, we investigate the effects of external environmental and internal psychological factors on linguistic positivity. Results showed a significant decline in both positive and negative expressions, indicating a broader societal move from emotionality to rationality in the USA over the past two centuries. Our findings also demonstrated that major wars, unemployment rates, and subjective happiness significantly affect changes in positivity. Notably, while major conflicts generally exert downward pressure on the linguistic positivity, broader historical, socio-cultural, and technological contexts can shape and at times counterbalance this effect, as evidenced by the contrasting linguistic responses to the Korean and Vietnam Wars. This study offers valuable insights into how language mirrors and responds to societal values and historical events. By detailing the interaction between language use and various influencing factors, our research suggests that combining word-level and sentence-level linguistic positivity bias analysis might offer potential applications for monitoring collective well-being and societal trends, enabling more responsive interventions.

摘要： 本研究基于一个 4.3 亿词次的结构化历史语料库，考察 1820 年代至 2000 年代美国通用英语中语言积极性的变化，并探讨外部环境因素和内部心理因素对语言积极性的影响。结果显示，积极表达和消极表达均显著减少，表明近两百年来美国社会整体上经历了从情绪化到理性化的转变。研究还发现，重大战争、失业率和主观幸福感对积极性的变化有显著影响。值得注意的是，重大冲突通常会压低语言积极性，但更宏观的历史、社会文化和技术背景能够塑造、有时甚至抵消这种影响——朝鲜战争与越南战争引发的截然不同的语言反应即为例证。本研究揭示了语言如何映照并回应社会价值观与历史事件。通过细致呈现语言使用与多种影响因素之间的互动，研究表明，将词层面与句层面的语言积极性偏向分析相结合，有望用于监测集体幸福感和社会趋势，从而支持更及时的干预。