The Impact of Generative AI on Code Expertise Models: An Exploratory Study
Abstract
Generative Artificial Intelligence (GenAI) tools for source code generation have significantly boosted productivity in software development. However, they also raise concerns, particularly the risk that developers may rely heavily on these tools, reducing their understanding of the generated code. We hypothesize that this loss of understanding may be reflected in source code knowledge models, which are used to identify developer expertise. In this work, we present an exploratory analysis of how a knowledge model and a Truck Factor algorithm built upon it can be affected by GenAI usage. To investigate this, we collected statistical data on the integration of ChatGPT-generated code into GitHub projects and simulated various scenarios by adjusting the degree of GenAI contribution. Our findings reveal that most scenarios led to measurable impacts, indicating the sensitivity of current expertise metrics. This suggests that as GenAI becomes more integrated into development workflows, the reliability of such metrics may decrease.
Keywords:
generative artificial intelligence, source code expertise, truck factor, mining software repository
References
Hervé Abdi. 2007. The Kendall rank correlation coefficient. Encyclopedia of measurement and statistics 2 (2007), 508–510.
Nuri Almarimi, Ali Ouni, Moataz Chouchen, and Mohamed Wiem Mkaouer. 2021. csDetector: an open source tool for community smells detection. In 29th ACM Joint Meeting on European Software Engineering Conference and Symposium on the Foundations of Software Engineering. 1560–1564.
Daniel Atzberger, Nico Scordialo, Tim Cech, Willy Scheibel, Matthias Trapp, and Jürgen Döllner. 2022. CodeCV: Mining expertise of GitHub users from coding activities. In 2022 IEEE 22nd International Working Conference on Source Code Analysis and Manipulation (SCAM). IEEE, 143–147.
Guilherme Avelino, Leonardo Passos, Andre Hora, and Marco Tulio Valente. 2016. A novel approach for estimating truck factors. In 2016 IEEE 24th International Conference on Program Comprehension (ICPC). IEEE, 1–10.
Guilherme Avelino, Marco Tulio Valente, and Andre Hora. [n. d.]. What is the Truck Factor of popular GitHub applications? A first assessment. PeerJ PrePrints 3 ( [n. d.]), e1233v1.
Moritz Beller, Amanda Park, Karim Nakad, Akshay Patel, Sarita Mohanty, Ford Garberson, Ian G Malone, Vaishali Garg, Henri Verroken, Andrew Kennedy, et al. 2025. What’s DAT? Three Case Studies of Measuring Software Development Productivity at Meta With Diff Authoring Time. arXiv preprint arXiv:2503.10977 (2025).
Christian Bird, Denae Ford, Thomas Zimmermann, Nicole Forsgren, Eirini Kalliamvakou, Travis Lowdermilk, and Idan Gazit. 2023. Taking flight with copilot. Commun. ACM 66, 6 (2023), 56–62.
Michelle Brachman, Amina El-Ashry, Casey Dugan, and Werner Geyer. 2025. Current and Future Use of Large Language Models for Knowledge Work. arXiv preprint arXiv:2503.16774 (2025).
Fabio Calefato, Marco Aurelio Gerosa, Giuseppe Iaffaldano, Filippo Lanubile, and Igor Steinmacher. 2022. Will you come back to contribute? Investigating the inactivity of OSS core developers in GitHub. Empirical Software Engineering 27, 3 (2022), 1–41.
Otávio Cury and Guilherme Avelino. 2024. Knowledge Islands: Visualizing Developers Knowledge Concentration. In Simpósio Brasileiro de Engenharia de Software (SBES). SBC, 789–795.
Otávio Cury and Guilherme Avelino. 2025. The Impact of Generative AI on Code Expertise Models: An Exploratory Study. DOI: 10.5281/zenodo.16969856
Otávio Cury, Guilherme Avelino, Pedro Santos Neto, Marco Túlio Valente, and Ricardo Britto. 2024. Source code expert identification: Models and application. Information and Software Technology (2024), 107445.
Otávio Cury, Guilherme Avelino, Pedro Santos Neto, Ricardo Britto, and Marco Túlio Valente. 2022. Identifying source code file experts. In 16th ACM/IEEE International Symposium on Empirical Software Engineering and Measurement. 125–136.
Paul Denny, James Prather, Brett A Becker, James Finnie-Ansley, Arto Hellas, Juho Leinonen, Andrew Luxton-Reilly, Brent N Reeves, Eddie Antonio Santos, and Sami Sarsa. 2024. Computing education in the era of generative AI. Commun. ACM 67, 2 (2024), 56–67.
Thomas Dohmke, Marco Iansiti, and Greg Richards. 2023. Sea change in software development: Economic and productivity analysis of the ai-powered developer lifecycle. arXiv preprint arXiv:2306.15033 (2023).
Neil A Ernst and Gabriele Bavota. 2022. Ai-driven development is here: Should you worry? IEEE Software 39, 2 (2022), 106–110.
Mívian Ferreira, Marco Tulio Valente, and Kecia Ferreira. 2017. A comparison of three algorithms for computing truck factors. In 2017 IEEE/ACM 25th International Conference on Program Comprehension (ICPC). IEEE, 207–217.
Thomas Fritz, Gail C Murphy, Emerson Murphy-Hill, Jingwen Ou, and Emily Hill. 2014. Degree-of-knowledge: Modeling a developer’s knowledge of code. ACM Transactions on Software Engineering and Methodology (TOSEM) 23, 2 (2014), 1–42.
Adam M Gaweda, Collin F Lynch, Nathan Seamon, Gabriel Silva de Oliveira, and Alay Deliwa. 2020. Typing exercises as interactive worked examples for deliberate practice in cs courses. In Proceedings of the Twenty-Second Australasian Computing Education Conference. 105–113.
Roberto Gozalo-Brizuela and Eduardo C Garrido-Merchán. 2023. A survey of Generative AI Applications. arXiv preprint arXiv:2306.02781 (2023).
Balreet Grewal, Wentao Lu, Sarah Nadi, and Cor-Paul Bezemer. 2024. Analyzing Developer Use of ChatGPT Generated Code in Open Source GitHub Projects. In 2024 IEEE/ACM 21st International Conference on Mining Software Repositories (MSR). IEEE, 157–161.
Christoph Hannebauer, Michael Patalas, Sebastian Stünkel, and Volker Gruhn. 2016. Automatically recommending code reviewers based on their expertise: An empirical comparison. In Proceedings of the 31st IEEE/ACM International Conference on Automated Software Engineering. 99–110.
Huizi Hao, Kazi Amit Hasan, Hong Qin, Marcos Macedo, Yuan Tian, Steven HH Ding, and Ahmed E Hassan. 2024. An Empirical Study on Developers Shared Conversations with ChatGPT in GitHub Pull Requests and Issues. arXiv preprint arXiv:2403.10468 (2024).
William Harding. 2025. AI Copilot Code Quality: Evaluating 2024’s Increased Defect Rate via Code Quality Metrics. White Paper. GitClear.
Elgun Jabrayilzade, Mikhail Evtikhiev, Eray Tüzün, and Vladimir Kovalenko. 2022. Bus factor in practice. In 44th International Conference on Software Engineering: Software Engineering in Practice. 97–106.
Kailun Jin, Chung-Yu Wang, Hung Viet Pham, and Hadi Hemmati. 2024. Can ChatGPT Support Developers? An Empirical Evaluation of Large Language Models for Code Generation. arXiv preprint arXiv:2402.11702 (2024).
Majeed Kazemitabaar, Oliver Huang, Sangho Suh, Austin Z Henley, and Tovi Grossman. 2024. Exploring the Design Space of Cognitive Engagement Techniques with AI-Generated Code for Enhanced Learning. arXiv preprint arXiv:2410.08922 (2024).
Boxuan Ma, Li Chen, and Shin’ichi Konomi. 2024. Enhancing Programming Education with ChatGPT: A Case Study on Student Perceptions and Interactions in a Python Course. In International Conference on Artificial Intelligence in Education. Springer, 113–126.
Anh Nguyen-Duc, Beatriz Cabrero-Daniel, Adam Przybylek, Chetan Arora, Dron Khanna, Tomas Herda, Usman Rafiq, Jorge Melegati, Eduardo Guerra, Kai-Kristian Kemell, et al. 2023. Generative Artificial Intelligence for Software Engineering–A Research Agenda. arXiv preprint arXiv:2310.18648 (2023).
Stack Overflow. 2024. Overflow: 2024 State of Development Survey. [link] (2024).
Alan Peslak and Lisa Kovalchick. 2024. AI for coders: An analysis of the usage of ChatGPT and GitHub CoPilot. Issues in Information Systems 25, 4 (2024), 252–260.
James Prather, Brent N Reeves, Paul Denny, Brett A Becker, Juho Leinonen, Andrew Luxton-Reilly, Garrett Powell, James Finnie-Ansley, and Eddie Antonio Santos. 2023. “It’s Weird That it Knows What I Want”: Usability and Interactions with Copilot for Novice Programmers. ACM Transactions on Computer-Human Interaction 31, 1 (2023), 1–31.
James Prather, Brent N Reeves, Juho Leinonen, Stephen MacNeil, Arisoa S Randrianasolo, Brett A Becker, Bailey Kimmel, Jared Wright, and Ben Briggs. 2024. The widening gap: The benefits and harms of generative ai for novice programmers. In Proceedings of the 2024 ACM Conference on International Computing Education Research-Volume 1. 469–486.
Martin P Robillard. 2021. Turnover-induced knowledge loss in practice. In Proceedings of the 29th ACM Joint Meeting on European Software Engineering Conference and Symposium on the Foundations of Software Engineering. 1292–1302.
Daniel Russo. 2024. Navigating the complexity of generative ai adoption in software engineering. ACMTransactions on Software Engineering and Methodology (2024).
James Skripchuk, Neil Bennett, Jeffrey Zhang, Eric Li, and Thomas Price. 2023. Analysis of Novices’ Web-Based Help-Seeking Behavior While Programming. In Proceedings of the 54th ACM Technical Symposium on Computer Science Education V. 1. 945–951.
Tao Xiao, Christoph Treude, Hideaki Hata, and Kenichi Matsumoto. 2024. Devgpt: Studying developer-chatgpt conversations. In Proceedings of the 21st International Conference on Mining Software Repositories. 227–230.
Ramazan Yilmaz and Fatma Gizem Karaoglan Yilmaz. 2023. Augmented intelligence in programming learning: Examining student views on the use of ChatGPT for programming learning. Computers in Human Behavior: Artificial Humans 1, 2 (2023), 100005.
Beiqi Zhang, Peng Liang, Xiyu Zhou, Aakash Ahmad, and Muhammad Waseem. 2023. Demystifying practices, challenges and expected features of using github copilot. arXiv preprint arXiv:2309.05687 (2023).
Albert Ziegler, Eirini Kalliamvakou, X Alice Li, Andrew Rice, Devon Rifkin, Shawn Simister, Ganesh Sittampalam, and Edward Aftandilian. 2024. Measuring GitHub Copilot’s Impact on Productivity. Commun. ACM 67, 3 (2024), 54–63.
Nuri Almarimi, Ali Ouni, Moataz Chouchen, and Mohamed Wiem Mkaouer. 2021. csDetector: an open source tool for community smells detection. In 29th ACM Joint Meeting on European Software Engineering Conference and Symposium on the Foundations of Software Engineering. 1560–1564.
Daniel Atzberger, Nico Scordialo, Tim Cech, Willy Scheibel, Matthias Trapp, and Jürgen Döllner. 2022. CodeCV: Mining expertise of GitHub users from coding activities. In 2022 IEEE 22nd International Working Conference on Source Code Analysis and Manipulation (SCAM). IEEE, 143–147.
Guilherme Avelino, Leonardo Passos, Andre Hora, and Marco Tulio Valente. 2016. A novel approach for estimating truck factors. In 2016 IEEE 24th International Conference on Program Comprehension (ICPC). IEEE, 1–10.
Guilherme Avelino, Marco Tulio Valente, and Andre Hora. [n. d.]. What is the Truck Factor of popular GitHub applications? A first assessment. PeerJ PrePrints 3 ( [n. d.]), e1233v1.
Moritz Beller, Amanda Park, Karim Nakad, Akshay Patel, Sarita Mohanty, Ford Garberson, Ian G Malone, Vaishali Garg, Henri Verroken, Andrew Kennedy, et al. 2025. What’s DAT? Three Case Studies of Measuring Software Development Productivity at Meta With Diff Authoring Time. arXiv preprint arXiv:2503.10977 (2025).
Christian Bird, Denae Ford, Thomas Zimmermann, Nicole Forsgren, Eirini Kalliamvakou, Travis Lowdermilk, and Idan Gazit. 2023. Taking flight with copilot. Commun. ACM 66, 6 (2023), 56–62.
Michelle Brachman, Amina El-Ashry, Casey Dugan, and Werner Geyer. 2025. Current and Future Use of Large Language Models for Knowledge Work. arXiv preprint arXiv:2503.16774 (2025).
Fabio Calefato, Marco Aurelio Gerosa, Giuseppe Iaffaldano, Filippo Lanubile, and Igor Steinmacher. 2022. Will you come back to contribute? Investigating the inactivity of OSS core developers in GitHub. Empirical Software Engineering 27, 3 (2022), 1–41.
Otávio Cury and Guilherme Avelino. 2024. Knowledge Islands: Visualizing Developers Knowledge Concentration. In Simpósio Brasileiro de Engenharia de Software (SBES). SBC, 789–795.
Otávio Cury and Guilherme Avelino. 2025. The Impact of Generative AI on Code Expertise Models: An Exploratory Study. DOI: 10.5281/zenodo.16969856
Otávio Cury, Guilherme Avelino, Pedro Santos Neto, Marco Túlio Valente, and Ricardo Britto. 2024. Source code expert identification: Models and application. Information and Software Technology (2024), 107445.
Otávio Cury, Guilherme Avelino, Pedro Santos Neto, Ricardo Britto, and Marco Túlio Valente. 2022. Identifying source code file experts. In 16th ACM/IEEE International Symposium on Empirical Software Engineering and Measurement. 125–136.
Paul Denny, James Prather, Brett A Becker, James Finnie-Ansley, Arto Hellas, Juho Leinonen, Andrew Luxton-Reilly, Brent N Reeves, Eddie Antonio Santos, and Sami Sarsa. 2024. Computing education in the era of generative AI. Commun. ACM 67, 2 (2024), 56–67.
Thomas Dohmke, Marco Iansiti, and Greg Richards. 2023. Sea change in software development: Economic and productivity analysis of the ai-powered developer lifecycle. arXiv preprint arXiv:2306.15033 (2023).
Neil A Ernst and Gabriele Bavota. 2022. Ai-driven development is here: Should you worry? IEEE Software 39, 2 (2022), 106–110.
Mívian Ferreira, Marco Tulio Valente, and Kecia Ferreira. 2017. A comparison of three algorithms for computing truck factors. In 2017 IEEE/ACM 25th International Conference on Program Comprehension (ICPC). IEEE, 207–217.
Thomas Fritz, Gail C Murphy, Emerson Murphy-Hill, Jingwen Ou, and Emily Hill. 2014. Degree-of-knowledge: Modeling a developer’s knowledge of code. ACM Transactions on Software Engineering and Methodology (TOSEM) 23, 2 (2014), 1–42.
Adam M Gaweda, Collin F Lynch, Nathan Seamon, Gabriel Silva de Oliveira, and Alay Deliwa. 2020. Typing exercises as interactive worked examples for deliberate practice in cs courses. In Proceedings of the Twenty-Second Australasian Computing Education Conference. 105–113.
Roberto Gozalo-Brizuela and Eduardo C Garrido-Merchán. 2023. A survey of Generative AI Applications. arXiv preprint arXiv:2306.02781 (2023).
Balreet Grewal, Wentao Lu, Sarah Nadi, and Cor-Paul Bezemer. 2024. Analyzing Developer Use of ChatGPT Generated Code in Open Source GitHub Projects. In 2024 IEEE/ACM 21st International Conference on Mining Software Repositories (MSR). IEEE, 157–161.
Christoph Hannebauer, Michael Patalas, Sebastian Stünkel, and Volker Gruhn. 2016. Automatically recommending code reviewers based on their expertise: An empirical comparison. In Proceedings of the 31st IEEE/ACM International Conference on Automated Software Engineering. 99–110.
Huizi Hao, Kazi Amit Hasan, Hong Qin, Marcos Macedo, Yuan Tian, Steven HH Ding, and Ahmed E Hassan. 2024. An Empirical Study on Developers Shared Conversations with ChatGPT in GitHub Pull Requests and Issues. arXiv preprint arXiv:2403.10468 (2024).
William Harding. 2025. AI Copilot Code Quality: Evaluating 2024’s Increased Defect Rate via Code Quality Metrics. White Paper. GitClear.
Elgun Jabrayilzade, Mikhail Evtikhiev, Eray Tüzün, and Vladimir Kovalenko. 2022. Bus factor in practice. In 44th International Conference on Software Engineering: Software Engineering in Practice. 97–106.
Kailun Jin, Chung-Yu Wang, Hung Viet Pham, and Hadi Hemmati. 2024. Can ChatGPT Support Developers? An Empirical Evaluation of Large Language Models for Code Generation. arXiv preprint arXiv:2402.11702 (2024).
Majeed Kazemitabaar, Oliver Huang, Sangho Suh, Austin Z Henley, and Tovi Grossman. 2024. Exploring the Design Space of Cognitive Engagement Techniques with AI-Generated Code for Enhanced Learning. arXiv preprint arXiv:2410.08922 (2024).
Boxuan Ma, Li Chen, and Shin’ichi Konomi. 2024. Enhancing Programming Education with ChatGPT: A Case Study on Student Perceptions and Interactions in a Python Course. In International Conference on Artificial Intelligence in Education. Springer, 113–126.
Anh Nguyen-Duc, Beatriz Cabrero-Daniel, Adam Przybylek, Chetan Arora, Dron Khanna, Tomas Herda, Usman Rafiq, Jorge Melegati, Eduardo Guerra, Kai-Kristian Kemell, et al. 2023. Generative Artificial Intelligence for Software Engineering–A Research Agenda. arXiv preprint arXiv:2310.18648 (2023).
Stack Overflow. 2024. Overflow: 2024 State of Development Survey. [link] (2024).
Alan Peslak and Lisa Kovalchick. 2024. AI for coders: An analysis of the usage of ChatGPT and GitHub CoPilot. Issues in Information Systems 25, 4 (2024), 252–260.
James Prather, Brent N Reeves, Paul Denny, Brett A Becker, Juho Leinonen, Andrew Luxton-Reilly, Garrett Powell, James Finnie-Ansley, and Eddie Antonio Santos. 2023. “It’s Weird That it Knows What I Want”: Usability and Interactions with Copilot for Novice Programmers. ACM Transactions on Computer-Human Interaction 31, 1 (2023), 1–31.
James Prather, Brent N Reeves, Juho Leinonen, Stephen MacNeil, Arisoa S Randrianasolo, Brett A Becker, Bailey Kimmel, Jared Wright, and Ben Briggs. 2024. The widening gap: The benefits and harms of generative ai for novice programmers. In Proceedings of the 2024 ACM Conference on International Computing Education Research-Volume 1. 469–486.
Martin P Robillard. 2021. Turnover-induced knowledge loss in practice. In Proceedings of the 29th ACM Joint Meeting on European Software Engineering Conference and Symposium on the Foundations of Software Engineering. 1292–1302.
Daniel Russo. 2024. Navigating the complexity of generative ai adoption in software engineering. ACMTransactions on Software Engineering and Methodology (2024).
James Skripchuk, Neil Bennett, Jeffrey Zhang, Eric Li, and Thomas Price. 2023. Analysis of Novices’ Web-Based Help-Seeking Behavior While Programming. In Proceedings of the 54th ACM Technical Symposium on Computer Science Education V. 1. 945–951.
Tao Xiao, Christoph Treude, Hideaki Hata, and Kenichi Matsumoto. 2024. Devgpt: Studying developer-chatgpt conversations. In Proceedings of the 21st International Conference on Mining Software Repositories. 227–230.
Ramazan Yilmaz and Fatma Gizem Karaoglan Yilmaz. 2023. Augmented intelligence in programming learning: Examining student views on the use of ChatGPT for programming learning. Computers in Human Behavior: Artificial Humans 1, 2 (2023), 100005.
Beiqi Zhang, Peng Liang, Xiyu Zhou, Aakash Ahmad, and Muhammad Waseem. 2023. Demystifying practices, challenges and expected features of using github copilot. arXiv preprint arXiv:2309.05687 (2023).
Albert Ziegler, Eirini Kalliamvakou, X Alice Li, Andrew Rice, Devon Rifkin, Shawn Simister, Ganesh Sittampalam, and Edward Aftandilian. 2024. Measuring GitHub Copilot’s Impact on Productivity. Commun. ACM 67, 3 (2024), 54–63.
Published
2025-09-22
How to Cite
CURY, Otávio; AVELINO, Guilherme.
The Impact of Generative AI on Code Expertise Models: An Exploratory Study. In: BRAZILIAN SYMPOSIUM ON SOFTWARE ENGINEERING (SBES), 39. , 2025, Recife/PE.
Anais [...].
Porto Alegre: Sociedade Brasileira de Computação,
2025
.
p. 706-712.
ISSN 2833-0633.
DOI: https://doi.org/10.5753/sbes.2025.11074.
