As you can see: Students picked the 4-letter option more often than any of the other options. Furthermore, students reported that the 4-letter option was “the most fun” with 71% agreement for that option compared to only 11% agreement for the 6-letter option. Interestingly, the 0-letter option received an agreement score of 0% (the 2-letter option a score of 17%). So, it seems to be the case that pure retrieval practice without hints rules self-testing out as a strategy that students would select. Consequently, providing some hints can make self-testing more enjoyable and make students select it more often when they are given the choice.
They followed up their first experiment with a second one where they only included the two extreme options for participants to choose from: 0-letter versus 6-letter option. They found that students went for the pure restudy (6-letter) option in approximately 80% of the trails versus 20% for the pure retrieval practice option (0-letter). This shows that a self-testing option that offers no hints is perceived as an unattractive option and in such a scenario, students will go for restudying as a strategy.
After establishing student preference for testing with hints, it is important to see if that kind of self-testing is actually beneficial for performance on a final test. In follow-up experiments, the authors showed that indeed all three retrieval practice options – independent of hint level (i.e., 0-, 2-, 4-letter) – increased performance on a final test given two minutes later; more than the pure restudy condition (6-letter). However, one important caveat seems to be to make sure that students actually engage in retrieval processes, i.e., actually retrieve information from memory. If, for instance, the word pairs allowed correct guessing of the target word given the cue word – instead of retrieval – providing more hints led to detrimental effects of performance.