To generate and implement a low processing classifier that can be executed in a low-cost and portable processor, linear discriminant analysis was the selected classifier with an overall accuracy of 96.67%. Since there are a total of three classes, Linear Discriminant Analysis generates three linear equations (y1, y2, y3) for each of the classes, when there is a new observation and it is evaluated into the three linear equations, the new observation will correspond to the equation of the class that produced the greatest value of the three.  These equations are later programmed in the Python classification program that is loaded into the Raspberry.
\(y_1 = \begin{vmatrix}-3.7388\\1.7168\\0.0664\end{vmatrix}x_F + 3.4469\)
\(y_2 = \begin{vmatrix}-3.9733\\0.0625\\-0.0683\end{vmatrix}x_F + 8.8381\)
\(y_3 = \begin{vmatrix}-7.7121\\1.7793\\-0.0019\end{vmatrix}x_F + 12.2850\)
From the above equations, y1 is the linear discriminant function of blink movements, y2 is the discriminant function of down eye movements, y3 is the linear discriminant function of up eye movements, xF is the feature input vector (Equation 11) of the EOG signal that is composed of the AVR value, the RMS, and Px value of the sampled EOG signal.
\[ \begin{vmatrix}ARV&RMS&PX\end{vmatrix} \]

Eye-tracking implementation in an embedded device. 

Now that the algorithm has been developed for the classification of the eye movements, it is necessary to implement the same algorithm and the whole processing methodology in an embedded system that can process the EOG signal in an easy manner. Since it is important to achieve both portability and easy usability in order that students or professors can make proper use of the eye tracking device, the selected embedded system was a Raspberry Pi 4 Model B Plus. The Raspberry Pi also denominated as a single-board computer or microcomputer is a small size electronic card that has the necessary hardware to perform capabilities similar to desktop computers or laptops but with the exception of not including peripherals such as a keyboard, display, or mouser, nonetheless, all these peripherals can be substituted with a small touchscreen display. The Raspberry main purpose is the promotion of the teaching of computer science in schools of developing countries, nonetheless, because of its low price and portability, this microcomputer has been used in research educational projects in the past \cite{K_lling_2016,Barker_2013}