# Automatic Evaluation of Piano Performances for STEAM Education
## 5 Experiments and Results
### Performance Dataset Description  
Piano performers in our dataset are played by piano teachers and learners ranging from the beginning level to the middle level. There are nine piano learners containing three groups: (i) kindergarten (4-5 years old), (ii) elementary school (7-10 years old), and (iii) junior high school (12-15 years old) for two consecutive years (2018-2020). In addition, there are four piano teachers participating in the data recording, and most of the piano teachers graduated and passed the piano exam of the Associated Board of the Royal Schools of Music (ABRSM) or Trinity's Piano certificate exams in grade 8 piano advanced level. The certifications are accepted worldwide. Currently, piano teachers teach piano at Yamaha Music School and KPN Music Academy in Thailand.  
We guaranteed that every participant was competent enough to provide beginner, intermediate, and advanced piano performances. By listening to the recordings repeatedly in terms of Legato scale, Staccato scale, and kids' song by referring to the song or scale to be the same as the original masterpieces, four experts' annotations were combined through a voting scheme to labels of Good, Normal, and Bad performance.  
In the musical performance, a \"good\" performance must consist of sharp sounds and straight notes. This could be generated by pressing the keypad with accurate hand weight and not missing the keypad. Moreover, when the performer plays a \"good\" performance, it is essential that they transmit the emotion by capturing the right style, mood, and tone of the song. They must as well scale the correct notes and play with accurate performance techniques such as dynamic articulation (Staccato, Legato, Tie, Slur, and etc.) and expression timing (measures or bars as whole note, half note, quarter note, and eight-note, respectively.) From the \"good\" performance listed above, it is highly required for piano performers to achieve the criteria while playing on stage or in piano competitions.  
As for \"normal\" performances, there may be some errors when pressing the piano keypad. For example, when piano performers play the scale, they may make mistakes  
\begin{table}
\begin{tabular}{c c c} \hline \hline \multicolumn{3}{c}{**Descriptions**} \\ \hline Sampling rate & 22,050 Hz \\ Channel & monophonic \\ Resolution & 16 bits \\ Microphone model & Audio-technical serial no. AT9931 PC \\ \hline \hline \end{tabular}
\end{table}
Table 1: Recording equipment and specifications.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multicolumn{1}{c}{**Major Scales**} & \begin{tabular}{c} **Number of** \\ **Accidentals** \\ \end{tabular} & \
\begin{tabular}{c} **Minor Scales** \\ **(a)** \\ \end{tabular} &
\begin{tabular}{c} **Number of** \\ **(b)** \\ \end{tabular} \\ \hline C Major & No & D Minor & 1 Flat \\ F Major & 1 Flat & E Minor & 1 Sharp \\ G Major & 1 Sharp & A Minor & No \\ \hline \hline \end{tabular}
\end{table}
Table 2: The Category of Scales and Accidentals.  
such that one or two keypads are pressed simultaneously. Furthermore, in terms of the playing style and technique in \"normal\" performance, there might be issues in transmitting emotion and expression, resulting in the performer unintentionally playing with unclear articulation and some note errors.