ON THE NECESSITY OF PRELIMINARY REQUISITIONS IN UNDERGRADUATE ELECTRICAL ENGINEERING STUDIES

In undergraduate studies, except for the first semester, almost every course has its own pre-requisitions list. This list contains all the courses that the student must have studied and passed before taking the current course.

In this work the author examines the relationship between several courses and their pre-requisition courses to determine when pre-requisitions are actually required. The database contains 490 students, studying Electronics and Electrical Engineering towards the degree of Bachelor in Science. The first pair of courses examined are named "Electronics 1") and "Electronics 2". In the first course the students learn about linear circuits and in the second course they learn how to solve circuits with non-linear elements by using linear approximations taught in Electronics 1. Clearly students must learn to master their linear circuits before they can solve non-linear circuits. The author used the database of six consecutive years to determine the correlation between the individual grades in the final exam in the preliminary course and the grades in the following course. Although not every student who did well in Electronics 1 did the same in Electronics 2, it is quite clear from the results that there is a strong correlation between succeeding in the preliminary course and succeeding in the successive course, and the relation is almost linear.

Next the author examined two other obligatory courses, "Signals and systems" and "Introduction to Electronic Communications". For eight years, the first course was a pre-requisition for the second one although "Signals and systems" focuses on discrete-time signals and systems while "Introduction to Electronic Communications" deals almost exclusively with continuous-time communication systems. The correlation between individual grades in these two courses was slightly smaller than in athe previous case and no clear relation between the grades of both courses was observed.

After 8 years the head of department decided to swap these two courses since he wanted students to be acquainted with communication systems at an earlier stage. The average grade in "Introduction to Electronic Communications" remained almost the same indicating that "Signals and Systems" was not really required, but the correlation coefficient between the courses dropped by almost 50% indicating that knowledge in communication systems does not necessarily lead to knowledge in signals and systems.

Finally, the non-obligatory specialization course "Digital Communications" was compared with its pre-requisition "Introduction to Electronic Communications" and the result was an extremely low correlation, suggesting the analogue communications and digital communications do not have a lot in common. The average grade in "Digital Communications" was rather high and most grades were in close vicinity to this number while the grades in "Introduction to Electronic Communications" covered a very vast range (larger standard deviation).
To summarize, it is important to re-evaluate pre-requisitions consistently as in some cases students are not allowed to register for courses, due to not passing their pre-requisitions although the later courses are not really required.