Optical observations from a ground-based astrometric instrument provide a unique set of data sensitive to variations of local plumb line, which represent the change of local gravitational field on the
Through theoretical derivation, some properties of the total least squares estimation are found. The total least squares estimation is the linear transformation of the least squares estimation, and th
This paper presents three strategies for modeling the regional empirical T_m (the weighted mean temperature of the atmosphere) to obtain more accurate determinations in a regional empirical model that