Research Article | | Peer-Reviewed

A Machine Learning Approach to Assessing Tax Cuts and Economic Growth in Ghana

Received: 26 July 2026     Accepted: 7 August 2026     Published: 23 October 2026
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Abstract

This study investigates the impact of tax cuts on Ghana's economic growth using a machine-learning approach applied to thirty-five years of macroeconomic data. The analysis focuses on the corporate income tax (CIT) rate, the personal income tax (PIT) rate, foreign direct investment (FDI), inflation, and the sectoral contributions of oil, gold, and cocoa to gross domestic product (GDP). Three feature-engineering strategies namely original, first-differenced, and ratio-transformed variables were used to train and compare an Extreme Gradient Boosting (XGBoost) regression model. The model trained on ratio-transformed features achieved the strongest predictive performance, with a coefficient of determination (R2) of 0.9737, a mean absolute percentage error (MAPE) of 4.12%, and a mean percentage error (MPE) of 0.0986%, substantially outperforming the models trained on the original and first-differenced features. SHapley Additive exPlanations (SHAP) were then applied to interpret the model's predictions. The SHAP analysis shows that higher CIT and PIT rates are consistently associated with lower GDP growth, while FDI inflows and commodity export revenues (particularly gold and oil) are associated with higher growth. These findings suggest that reducing corporate and personal income tax rates could support economic growth in Ghana, but that the benefits of such cuts are likely to be realized only alongside complementary policies that improve investment efficiency, strengthen tax compliance, and add value to commodity exports.

Published in American Journal of Applied Mathematics (Volume 14, Issue 5)
DOI 10.11648/j.ajam.20261405.20
Page(s) 364-379
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2026. Published by Science Publishing Group

Keywords

Tax Cuts, Corporate Income Tax, Personal Income Tax, XGBoost, Machine Learning, SHAP Analysis, Ghana, Economic Growth

References
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Cite This Article
  • APA Style

    Ampofi, I., Arhinful, D. A., Nti, A. E., Mawutor, E. (2026). A Machine Learning Approach to Assessing Tax Cuts and Economic Growth in Ghana. American Journal of Applied Mathematics, 14(5), 364-379. https://doi.org/10.11648/j.ajam.20261405.20

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    ACS Style

    Ampofi, I.; Arhinful, D. A.; Nti, A. E.; Mawutor, E. A Machine Learning Approach to Assessing Tax Cuts and Economic Growth in Ghana. Am. J. Appl. Math. 2026, 14(5), 364-379. doi: 10.11648/j.ajam.20261405.20

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    AMA Style

    Ampofi I, Arhinful DA, Nti AE, Mawutor E. A Machine Learning Approach to Assessing Tax Cuts and Economic Growth in Ghana. Am J Appl Math. 2026;14(5):364-379. doi: 10.11648/j.ajam.20261405.20

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  • @article{10.11648/j.ajam.20261405.20,
      author = {Isaac Ampofi and Daniel Andoh Arhinful and Alex Emmanuel Nti and Ernest Mawutor},
      title = {A Machine Learning Approach to Assessing Tax Cuts and Economic Growth in Ghana},
      journal = {American Journal of Applied Mathematics},
      volume = {14},
      number = {5},
      pages = {364-379},
      doi = {10.11648/j.ajam.20261405.20},
      url = {https://doi.org/10.11648/j.ajam.20261405.20},
      eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajam.20261405.20},
      abstract = {This study investigates the impact of tax cuts on Ghana's economic growth using a machine-learning approach applied to thirty-five years of macroeconomic data. The analysis focuses on the corporate income tax (CIT) rate, the personal income tax (PIT) rate, foreign direct investment (FDI), inflation, and the sectoral contributions of oil, gold, and cocoa to gross domestic product (GDP). Three feature-engineering strategies namely original, first-differenced, and ratio-transformed variables were used to train and compare an Extreme Gradient Boosting (XGBoost) regression model. The model trained on ratio-transformed features achieved the strongest predictive performance, with a coefficient of determination (R2) of 0.9737, a mean absolute percentage error (MAPE) of 4.12%, and a mean percentage error (MPE) of 0.0986%, substantially outperforming the models trained on the original and first-differenced features. SHapley Additive exPlanations (SHAP) were then applied to interpret the model's predictions. The SHAP analysis shows that higher CIT and PIT rates are consistently associated with lower GDP growth, while FDI inflows and commodity export revenues (particularly gold and oil) are associated with higher growth. These findings suggest that reducing corporate and personal income tax rates could support economic growth in Ghana, but that the benefits of such cuts are likely to be realized only alongside complementary policies that improve investment efficiency, strengthen tax compliance, and add value to commodity exports.},
     year = {2026}
    }
    

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  • TY  - JOUR
    T1  - A Machine Learning Approach to Assessing Tax Cuts and Economic Growth in Ghana
    AU  - Isaac Ampofi
    AU  - Daniel Andoh Arhinful
    AU  - Alex Emmanuel Nti
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    N1  - https://doi.org/10.11648/j.ajam.20261405.20
    DO  - 10.11648/j.ajam.20261405.20
    T2  - American Journal of Applied Mathematics
    JF  - American Journal of Applied Mathematics
    JO  - American Journal of Applied Mathematics
    SP  - 364
    EP  - 379
    PB  - Science Publishing Group
    SN  - 2330-006X
    UR  - https://doi.org/10.11648/j.ajam.20261405.20
    AB  - This study investigates the impact of tax cuts on Ghana's economic growth using a machine-learning approach applied to thirty-five years of macroeconomic data. The analysis focuses on the corporate income tax (CIT) rate, the personal income tax (PIT) rate, foreign direct investment (FDI), inflation, and the sectoral contributions of oil, gold, and cocoa to gross domestic product (GDP). Three feature-engineering strategies namely original, first-differenced, and ratio-transformed variables were used to train and compare an Extreme Gradient Boosting (XGBoost) regression model. The model trained on ratio-transformed features achieved the strongest predictive performance, with a coefficient of determination (R2) of 0.9737, a mean absolute percentage error (MAPE) of 4.12%, and a mean percentage error (MPE) of 0.0986%, substantially outperforming the models trained on the original and first-differenced features. SHapley Additive exPlanations (SHAP) were then applied to interpret the model's predictions. The SHAP analysis shows that higher CIT and PIT rates are consistently associated with lower GDP growth, while FDI inflows and commodity export revenues (particularly gold and oil) are associated with higher growth. These findings suggest that reducing corporate and personal income tax rates could support economic growth in Ghana, but that the benefits of such cuts are likely to be realized only alongside complementary policies that improve investment efficiency, strengthen tax compliance, and add value to commodity exports.
    VL  - 14
    IS  - 5
    ER  - 

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Author Information
  • Department of Mathematical Sciences, University of Mines and Technology, Tarkwa, Ghana

  • Department of Mathematical Sciences, University of Mines and Technology, Tarkwa, Ghana

  • Department of Mathematical Sciences, University of Mines and Technology, Tarkwa, Ghana

  • Department of Mathematical Sciences, University of Mines and Technology, Tarkwa, Ghana

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