<p>Performance statistics (mean ± standard deviation of R²) for calibration models fitted independently to each sensor cluster. The humidity correction functions f(RH) and k(RH) are implemented according to Eqs. (2) and (3), respectively. Predictor variables raised to the 0th power indicate exclusion from the regression model. The highest-performing model is marked in bold, while the second and third-ranked models are shown in italics.</p>

Performance statistics (mean ± standard deviation of R2) for calibration models fitted independently to each sensor cluster. The humidity correction functions f(RH) and k(RH) are implemented according to Eqs. (2) and (3), respectively. Predictor variables raised to the 0th power indicate exclusion from the regression model. The highest-performing model is marked in bold, while the second and third-ranked models are shown in italics.