Retrieving information by testing improves subsequent retention more than restudy, a phenomenon known as the retrieval practice effect. According to the retrieval effort hypothesis (REH), difficult items require more retrieval effort than easier items and, consequently, should benefit more from retrieval practice. In two experiments, we tested this prediction. Participants learned sets of easy and difficult Swahili–Portuguese word pairs (study phase) and repeatedly restudied half of these items and repeatedly retrieval practiced the other half (practice phase). Forty-eight hours later, they took a cued-recall test (final test phase). In both experiments, we replicated both the retrieval practice and the item difficulty effects. In Experiment 1 (N = 51), we found a greater retrieval practice effect for easy items, MDifference = .26, SD = .17, than for difficult items, MDifference = .19, SD = .19, t(50) = 2.01, p = .05, d = 0.28. In Experiment 2 (N = 28), we found a nonsignificant trend—F(1, 27) = 2.86, p = .10, $$ {\upeta}_{\mathrm{p}}^2 $$ = .10—toward a greater retrieval practice effect for difficult items, MDifference = .28, SD = .22, than for easy items, MDifference = .18, SD = .21. This was especially true for individuals who benefit from retrieval practice (difficult: MDifference = .32, SD = .18; easy: MDifference = .20, SD = .20), t(24) = –2.08, p = .05, d = –0.42. The results provide no clear evidence for the REH and are discussed in relation to current accounts of the retrieval practice effect.

中文翻译：

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项目难度会影响检索练习效果的大小吗？检索努力假设的评估

通过测试检索信息比重新研究更能提高后续保留，这种现象被称为检索练习效果。根据检索努力假说（REH），困难的项目比容易的项目需要更多的检索工作，因此应该从检索练习中受益更多。在两个实验中，我们测试了这个预测。参与者学习了一组简单和困难的斯瓦希里语-葡萄牙语单词对（学习阶段），并反复重新研究这些项目的一半，并反复检索练习另一半（练习阶段）。四十八小时后，他们进行了线索回忆测试（最终测试阶段）。在这两个实验中，我们都复制了检索实践和项目难度效应。在实验 1 (ñ= 51），我们发现对于容易的项目有更大的检索练习效果，米区别= .26,标清= .17，比困难的项目，米区别= .19,标清= .19,吨(50) = 2.01,p= .05,d= 0.28。在实验 2 (ñ= 28)，我们发现了一个不显着的趋势——F(1, 27) = 2.86,p= .10, $$ {\upeta}_{\mathrm{p}}^2 $$ = .10——对困难项目有更大的检索练习效果，米区别= .28,标清= .22，比简单的项目，米区别= .18,标清= .21。对于从检索实践中受益的个人来说尤其如此（困难：米区别= .32,标清= .18; 简单：米区别= .20,标清= .20),吨(24) = –2.08,p= .05,d= –0.42。该结果没有为 REH 提供明确的证据，并结合当前对检索实践效果的描述进行了讨论。