Open educational resources (OER) are increasingly attractive options for reducing educational costs, yet controlled studies of their efficacy are lacking. The current study addressed many criticisms of past research by accounting for course and instructor characteristics in comparing objective student learning outcomes across multiple sections of General Psychology taught by trained graduate student instructors at a large research-intensive university. We found no evidence that use of the OER text impeded students' critical thinking compared to use of a traditional textbook, even after accounting for instructor characteristics. To the contrary, we found evidence of a slight increase in content knowledge when using an OER text. Importantly, this effect was driven by improvements from both our lowest-performing students and our highest-performing students. Moreover, student learning outcomes were not influenced by instructor experience, suggesting even novice instructors fared well with OER materials. Finally, students from traditionally underserved populations reported the lower cost of the book had a significantly higher impact on their decision to enroll in and remain enrolled in the course.

中文翻译：

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当受过培训的研究生导师改用开放式教科书时会发生什么？对学生学习成果影响的对照研究

开放教育资源 (OER) 是越来越有吸引力的降低教育成本的选择，但缺乏对其功效的对照研究。当前的研究通过在比较由大型研究密集型大学受过训练的研究生教师教授的普通心理学多个部分的客观学生学习成果时考虑课程和教师特征，解决了对过去研究的许多批评。我们没有发现任何证据表明，与使用传统教科书相比，使用 OER 文本会阻碍学生的批判性思维，即使在考虑到教师特征之后也是如此。相反，我们发现使用 OER 文本时内容知识略有增加的证据。重要的，这种效果是由我们表现最差的学生和表现最好的学生的进步所推动的。此外，学生的学习成果不受教师经验的影响，这表明即使是新手教师也能很好地使用 OER 材料。最后，来自传统上服务不足人群的学生报告说，这本书的较低成本对他们参加和继续参加该课程的决定的影响要大得多。