Every time the student opens the practice tool the question is loaded automatically. The authors modified the SuperMemo 2, which had following properties to update question y for the student x:

1. i_intervall$_{xy}$ - the number of days remaining to ask question y from student x.
2. e_factor$_{xy}$ - how easy question y is for student x
3. q$_{xy}$ - the correctness of student x’s answer to question y. (value between 1-5)

MODIFICATIONS

1. The algorithm was applied to the topics, instead of single questions and the questions for that topic were asked using Round-robin scheduling.
2. q$_{xy}$ is purely based on the correctness of the answer. In this paper the authors used several factors:

I. d${xy}$ - the duration of the time student x spent answering question y, measured in minutes. II. t${xy}$ - the number of attempts student x made before submitting their final answer for question y. III. v${xy}$ - the number of other textbook pages viewed while answering question y;

The values for the q${xy}$ where chosen in the following manner: (1) q${xy}$= 5 if v${xy}$ == 0, t${xy}$<= 1, and d${xy}$ <= 2; (2) q${xy}$= 4 if t${xy}$ <= 2 and d${xy}$ <= 2; (3) q${xy}$ = 3 if t${xy}$ <= 3 and d${xy}$ <= 3; (4) q${xy}$ = 2 if t${xy}$ <= 4 and d${xy}$ <= 4; (5) q${xy}$= 1 if correct, but other conditions were not met; (6) q${xy}$ = 0 if the final answer was incorrect.