Testing yourself is often an effective way to improve your ability to retrieve a skill. Young offers two methods to improve retrieval rates. Firstly, you can review your learning materials. Specifically, go back over the materials you used when you first studied this topic. The alternative to recalling facts and concepts from memory is significantly more effective. Young cites a 2011 study from Purdue University that found recall is far more effective for long-term learning retention. Despite this, most learners fall back on reviewing old material.