The testing effect and the complexity of the learning material: The adequacy of the knowledge base as a moderator?

测试效果（即在初次学习后练习检索比其他重新学习技巧更有效的发现）是在实验室长期学习中研究得最好的发现之一，尽管只有少数研究包括超过一到两周的延迟。由于几项研究也报告了测试在该领域的效果，因此建议将检索练习应用于课堂。然而，检索练习被认为不利于学习更复杂的材料，事实上，一些使用复杂材料的研究并没有观察到测试效果。如果这个假设是正确的，那么测试在学校教育中的适用性显然会受到损害。相反，如果过早地放弃对更复杂的材料有益的检索练习，学习者将被剥夺持久学习的最有效的技术之一，特别是那些通常学习更复杂主题的人。在我们的项目中，我们想要测试一种对先前使用复杂材料的发现的替代解释，即学习者在巩固阶段开始时没有充分理解主题，这导致检索练习的效果不如使用不那么复杂的材料。因此，我们想要检验这样一个假设，即即使是复杂的学习材料，如果学习者在最初的学习阶段充分理解了学习材料，或者在练习检索时有机会重新学习材料，也会产生测试效应。为了验证我们的假设，我们将在高中11年级的德语课堂上构建一个课程主题的文本材料（魏玛古典主义运动的文化和历史背景），并操纵它们的命题复杂性。这些材料将在五个高中课堂实验中应用，最终测试延迟八周。此外，我们将采取措施增加学习者在练习检索时建立足够知识库的可能性，或者在练习检索时改进知识库。在子项目A中，我们将在巩固阶段、额外的初始研究阶段或关键概念的预培训之前应用度量。在巩固阶段，复习和闭卷考试将进行比较。在子项目B中，我们将在巩固阶段采取措施：将开卷测试的两种变体（有或没有提示，以便在没有文本的情况下尽可能多地回忆信息）与重新学习和闭卷测试进行比较。开卷测试应该结合测试和重新学习的好处，因此对于复杂的材料应该特别有利。最后，将在联合研究中比较这些研究中针对复杂材料的最有效措施。这项调查应该为如何最好地理解和巩固复杂文本提供（暂定）建议的基础。

The testing effect (i.e., the finding that practicing retrieval after initial study is more effective than other restudy techniques) is one of the best-researched findings on long-term learning in the laboratory, although only a few studies have included delays longer than one or two weeks. Since several studies have also reported testing effects in the field, retrieval practice has been recommended to be applied in the classroom. However, retrieval practice has been suggested to be not beneficial for learning with more complex materials and, indeed, several studies using complex materials did not observe a testing effect. If this assumption was true, the applicability of testing in school education would clearly be compromised. Conversely, if retrieval practice is prematurely discarded as beneficial for more complex materials, learners would be deprived of one of the most effective techniques for lasting learning, especially those who are typically learning more complex subject matter. In our project, we want to test an alternative explanation for previous findings with complex materials, namely that learners had not adequately understood the subject matter by the time the consolidation phase started, which resulted in less effective retrieval practice than with less complex materials. Thus, we want to test the hypothesis that the testing effect will occur even with complex learning materials if learners adequately understand the learning material in the initial learning phase or have the opportunity to restudy the material while practicing retrieval.To test our assumption, we will construct text materials on a curricular topic in 11th-grade German classes in high school (the cultural and historic context of the Weimar Classicism movement) and manipulate their propositional complexity. These materials will be applied in five experiments in high school classrooms with a final test delay of eight weeks. In addition, we will apply measures to increase the likelihood that learners have built an adequate knowledge base by the time they practice retrieval or to improve it while they practice retrieval. In Subproject A, we will apply measures before the consolidation phase, an additional initial study phase or a pre-training on key concepts. In the consolidation phase, restudying and a closed-book test will be compared. In Subproject B, we will apply measures during the consolidation phase: two variants of open-book tests (with vs. without prompts to recall as much information as possible without the text) will be compared to restudying and a closed-book test. Open-book tests should combine the benefits of testing and restudying and should therefore be particularly advantageous for complex materials. Finally, the most effective measures for complex materials in those studies will be compared in a joint study. This investigation should provide a basis for (tentative) recommendations on how to best comprehend and consolidate complex texts.