Open Access (OA) facilitates access to articles. But, authors or funders often must pay the publishing costs preventing authors who do not receive financial support from participating in OA publishing and citation advantage for OA articles. OA may exacerbate existing inequalities in the publication system rather than overcome them. To investigate this, we studied 522,411 articles published by Springer Nature. Employing correlation and regression analyses, we describe the relationship between authors affiliated with countries from different income levels, their choice of publishing model, and the citation impact of their papers. A machine learning classification method helped us to explore the importance of different features in predicting the publishing model. The results show that authors eligible for APC waivers publish more in gold-OA journals than others. In contrast, authors eligible for an APC discount have the lowest ratio of OA publications, leading to the assumption that this discount insufficiently motivates authors to publish in gold-OA journals. We found a strong correlation between the journal rank and the publishing model in gold-OA journals, whereas the OA option is mostly avoided in hybrid journals. Also, results show that the countries' income level, seniority, and experience with OA publications are the most predictive factors for OA publishing in hybrid journals.

翻译：开放获取（OA）促进了文章的获取。但作者或资助者通常需承担出版成本，这使得缺乏资金支持的作者难以参与OA出版，且OA文章存在引文优势。OA可能加剧而非消除出版体系中的现有不平等。为探究此问题，我们研究了斯普林格·自然出版的522,411篇文章。通过相关性与回归分析，我们揭示了不同收入水平国家作者、其出版模式选择以及论文引用影响力之间的关系。机器学习分类方法帮助我们探索了预测出版模式时不同特征的重要性。结果表明，符合APC豁免条件的作者在金色OA期刊上发表的文章多于其他作者。相反，符合APC折扣条件的作者OA出版比例最低，这暗示该折扣不足以激励作者在金色OA期刊上发表文章。我们发现金色OA期刊的期刊排名与出版模式之间存在强相关性，而在混合期刊中，作者大多避免选择OA选项。此外，结果显示，国家收入水平、资历以及OA出版经验是预测混合期刊中OA出版的最关键因素。