Ownership structure, board characteristics, and tax aggressiveness

Tax aggressiveness, as commonly proxied by the effective tax rate (ETR), measures a firm’s effort spent on minimizing its tax payments. It is suggested that more tax aggressive firms have greater incentives to allocate resources to minimize taxes and thus have lower ETRs. Corporate governance has been continuously receiving attention in literature across different fields and can affect a firm’s tax strategy through its control mechanism. This thesis investigates how corporate governance influences a firm’s tax aggressiveness. The main hypothesis of this thesis is whether firms with good corporate governance will have less incentives and opportunities to manage tax aggressively. Specifically, I take advantages of the distinct institutional settings in China to study whether the Chinese firm’s tax aggressiveness is affected by ownership structure and the characteristics of board of directors. Using all non-financial listed companies in the Chinese A-share market during 2003 and 2009 period, I find that firms with state-controlled nature and lower proportion of controlling shares pursue less aggressive tax strategies and maintain higher ETRs. In addition, my finding is consistent with prior literature that a higher percentage of the boards’ shareholdings and dual service duties performed by the board chairman result in lower ETRs. However, I do not find a significant relationship between the percentage of independent directors and tax aggressiveness which may suggest the ineffective role of independent directors in China

Surface-wave group-delay and attenuation kernels

We derive both 3-D and 2-D Fréchet sensitivity kernels for surface-wave group-delay and anelastic attenuation measurements. A finite-frequency group-delay exhibits 2-D off-ray sensitivity either to the local phase-velocity perturbation δc/c or to its dispersion ω(∂/∂ω)(δc/c) as well as to the local group-velocity perturbation δC/C. This dual dependence makes the ray-theoretical inversion of measured group delays for 2-D maps of δC/C a dubious procedure, unless the lateral variations in group velocity are extremely smooth