Replication Data and Excel Template for \"A Simplified Guide for Weighted Fitting and its Significance in Separation Science\"

Weighted least squares (WLS) improves calibration accuracy, especially at low analyte concentrations where ordinary least squares (OLS) fails. Chromatographic data often exhibits heteroscedastic noise, making WLS a better choice than OLS for regression. A step-by-step WLS guide using high-performance liquid chromatography–ultraviolet (HPLC–UV) data for carbamazepine demonstrates reduced quantitation errors. WLS can be implemented easily in Excel, offering analysts a cost-effective tool for robust quantitation.