NUMERICAL HALLUCINATION IN SOLVER: INTEGRITY BREAKDOWN UNDER REGIONAL SETTINGS IN Â Â Â Â Â Â Â Â MICROSOFT EXCEL
Abstract
This study investigates a critical computational behavior in Microsoft Excel associated with the use of Solver in optimization problems. In experiments conducted using the GRG Nonlinear method, it is observed that removing the integrality constraint (INT) may produce mathematically consistent results that are nevertheless incompatible with the model’s constraints. The phenomenon, termed numerical hallucination, is characterized by the generation of magnitudes incompatible with the feasible region. The analysis is based on models with explicit bounds subjected to different regional settings. The results indicate that the inconsistency does not originate in the solution process, but in the interpretation of data during state reconstruction, being directly associated with the use of decimal separators. Scenario restoration reveals this distortion by producing results that preserve algebraic consistency but violate the model’s constraints. It is further observed that enforcing the integrality constraint (INT) acts as a containment mechanism, whereas its removal exposes the system to susceptibility to scale distortions under certain configurations. It is concluded that the observed behavior does not arise from the optimization method itself, but from limitations in data interpretation, requiring rigorous verification of regional settings and constraints in continuous models.
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Author Biography
Writer and University Professor in topics related to the exact sciences and Educational Technologies. Master’s degree in Natural Sciences and Mathematics from the Regional University of Blumenau – FURB (2012). Specialist in Methodology of Mathematics Teaching – IBPEX (2006). Bachelor’s degree in Accounting from the University of the Region of Joinville – UNIVILLE (2000). Holds a Pedagogical Teaching Certification from the University Center of Jaraguá do Sul – UNERJ (2006). Professor in professional and technological education, at the levels of technical secondary education, undergraduate technological education, and graduate studies. Has over 20 years of experience in accounting, administrative, and production processes in the Vale do Itapocu region – SC.
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