“…Baker, Clarke-Midura, and Ocumpaugh 2016), as the achievement system built into games may not be the most informative indicator of learning (Heeter et al 2013). Some papers point out that their best predictors for measuring learning are based on the analysis of the player's exploration strategies (Käser, Hallinen, & Schwartz, 2017;Owen, Anton, and Baker 2016;Horn et al 2016;Smith, Hickmott, Southgate, Bille, & Stephens, 2016;Kang, Liu, and Qu 2017), or on the characteristics of player failures (Halverson and Owen 2014). One study explored the relation between learning and students' facial behavior (Z. Xu and Woodruff 2017).…”