The Preliminary Discussion of Measuring Accuracy of Sunspot Magnetic Fields in Yunnan Observatory

The preliminary comparisons of the sunspot magnetic field measurements of Yunnan Observatory with those of Mount Wilson Observatory (W) and the Soviet Union(S) give the correlation coefficients R_w=0.91 and R_s=0.97 total mean square errors are σ_w=5.7×10² G and σ_s=4.9×10²G respectively. There arc 0.39% of the sunspots marked with wrong polarities in the data of Yunnan Observatory, and 0.36% in those of Soviet Union. The better correlation R_s and the. smaller mean square error σ_s might be due to the smaller difference of the observation time between Yunnan Observatory and the Soviet Union.