A Spatially Dependent Correction of Gaia EDR3 Parallax Zero-point Offset based on 0.3 million LAMOST DR8 Giant Stars

We have studied the zero-point offset of Gaia early Data Release 3 (EDR3) parallaxes based on a sample 0.3 million giant stars built from LAMOST data with distance accuracy better than 8.5\%. The official parallax corrections largely reduce global in EDR3 parallaxes: offsets are $-$27.9 $\mu$as and $-$26.5 (before correction) $+$2.6 $+$2.9 (after for five- six-parameter solutions, respectively. bias raw measurements is significantly dependent $G$ magnitudes, spectral colors, positions stars. could patterns while not fully account spaces colors positions. In current paper, spatially correction model five-parameter solution footprint firstly provided advantage huge number our sample.