Field Experiment of the Memory Retention of Programmers Regarding Source Code

  • A. Fekete Eötvös Loránd University, Faculty of Informatics, Egyetem tér 1-3., 1053 Budapest, Hungary
  • Z. Porkoláb Eötvös Loránd University, Faculty of Informatics, Egyetem tér 1-3., 1053 Budapest, Hungary


Program comprehension is a continuously important topic in computer science since the spread of personal computers, and several program comprehension models have been identified as possible directions of active code comprehension. There has been little research on how much programmers remember the code they have once written. We conducted two experiments with a group of Computer Science MSc students. In the first experiment, we examined the code comprehension strategies of the participants. The students were given a task to implement a minor feature in a relatively small C++ project. In the second experiment, we asked the students 2 months later to complete the same task again. Before starting the clock, we asked the students to fill a questionnaire which aimed to measure program code-related memory retention: we inquired about how much the students remembered the code, down to the smallest relevant details, e.g. the name of functions and variables they had to find to complete the task.

After the second experiment, we could compare the solution times of those students who participated in both parts. As one result, we could see that these students could solve the task in shorter time than they did in the first experiment. We also looked at the results of the questionnaire: the vast majority of students could not precisely remember more than two or three identifiers from the original code. In this paper, we will show how this result compares to the forgetting curve.


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How to Cite
FEKETE, A.; PORKOLÁB, Z.. Field Experiment of the Memory Retention of Programmers Regarding Source Code. Studia Universitatis Babeș-Bolyai Informatica, [S.l.], v. 68, n. 1, p. 71-82, aug. 2023. ISSN 2065-9601. Available at: <>. Date accessed: 11 dec. 2023. doi: