Comparison of ﹩{R}_{8542}^{+}﹩ measurements for the cross-matched LAMOST and MaStar samples under two convolution schemes. The left panel shows the case in which Gaussian convolution is applied to both datasets, while the right panel shows the case in which the LAMOST spectra are convolved with the instrumental LSF and the MaStar spectra with a Gaussian kernel. In each panel, the upper subpanel presents the measured ﹩{R}_{8542}^{+}﹩ values as a function of T_eff, and the lower subpanel shows the residuals, defined as ﹩{R}_{8542,{\rm{LAMOST}}}^{+}-{R}_{8542,{\rm{MaStar}}}^{+}﹩. The median, scaled median absolute deviation (1.4826 × MAD), and Pearson correlation coefficient r are labeled in the lower subpanels. The gray dashed line marks the zero level.