# Online and In-Class Evaluation of a Music Theory E-Learning Platform
## 2 Related Work
### Previous Evaluations of the Platform  
The first version of the Troubadour platform provided a tool for students to consolidate their ear training further and overcome individual challenges through motivation for ear training. Initially, the interval dictation application was implemented into the platform (Figure 1). We conducted A/B testing to evaluate the platform's impact on the students' performance. The students of two classes in the first and second year were split into two groups. The control group did not use the platform (consisting of 14 students), whereas the test group did (consisting of 19 students). The test group used the platform for one month. At the end of the testing period, both groups took a conventional exam. Their results showed that better success was achieved by students who actively used the Troubadour platform. First-year students in the test group achieved 9.2% better results on average than those who trained only in a conventional way. Meanwhile, the difference in success among the second-year students was smaller--the test group students performed 1% better. The platform's data were also analyzed in the experiment, including the number of incorrect submissions of the exercise, the number of deletions or additions of notes, and the number of playback re-plays. The results showed all metrics decreased proportionally with the number of solved exercises.  
Later, in an updated version of the platform, a new rhythmic dictation application was developed [18]. We developed an algorithm to generate rhythmic sequences, which creates meaningful rhythmic patterns. Rhythmic pattern generation was more difficult than interval sequence generation, specifically in avoiding meaningless rhythmic sequences, which would demotivate the users. Each game in the rhythmic dictation application consisted of four rhythmic sequences. The student could fill in the perceived rhythm via the rhythmic keyboard (Figure 2). The user could also enable or disable the metronome and adjust the tempo and the playback volume.  
The rhythmic dictation application was also tested in a similar experiment to the one for the interval dictation application. During the experiment, the authors interviewed four students to assess the prototype user interface and improve the user experience. After this stage, the improved application was tested on a larger test group. The students were again divided into a control and a test group--there were 24 students in the control group and 23 in the test group. During the experiment, the control group practiced rhythmic dictation in a conventional way, while the test group used the platform in-class and at home. The experiment lasted five weeks.  
Within the experiment, the test group students also responded to a questionnaire about the user experience and the functionalities of the platform. All students agreed the platform was easy to use. Almost all students found the exercises challenging enough and quickly got used to the new rhythmic application. The questionnaire at the end of the test period also showed that the test group students almost completely stopped practicing in a conventional way as a result of the use of the platform.  
At the end of the evaluation period, the students were again evaluated through a conventional exam. The difference between the test and control groups in the first years was insignificant, while the second-year test group students achieved significantly better grades than the control group (average grade of 4.44 for the test group versus 3.58 for the  
Figure 1: Interval dictation application.  
Figure 2: Rhythmic dictation application.  
control group). The hypothesis that the use of the platform has a positive effect on the students' performance was therefore confirmed [18].