Investigating inversion uncertainties resulting from mode selections

The quality of an inversion depends on many factors. In addition to the well known ones, such as the target function, the surface term and the suppression parameters, different inversion codes utilizing different matrix inversion algorithms could also bring in an additional uncertainty. Therefore, it is important to assess the uncertainty and the stability of an inversion code prior using it to obtain any reliable result. The examination of our inversion code suggested the following: • low-degree low-order modes are essential for an accurate inversion; • when the quantity being inverted contains narrow features near the surface, the inversions using different mode sets would be inconsistent. In this paper, we show some representative results, in order to invite stimulating discussions and insightful suggestions.