In this paper, we examine the spillover effect of US monetary policy uncertainty (MPU) on China's real economic activities, and study the international transmission mechanisms of MPU shock from the view of financial integration, on both aggregate and firm level. Based on the macro level evidences, we find that an increase in US MPU will depress not only domestic output but also the real economic activities in China. The international spillover effect of US MPU shock will be intensified when international financial markets get more integrated. The firm level evidence based on Chinese listed firms further corroborate the deflationary effect of US MPU shock. Theoretically, we build a two-country New Keynesian DSGE model featuring monetary uncertainty shocks to confirm the empirical evidences.

This study adopts the Markov-switching ARCH (hereafter SWARCH) model to examine the volatility nature and volatility linkages of four segmented Chinese stock indices (SHA, SZA, SHB, and SZB). Our empirical findings are consistent with the following notions. First, we find strong evidence of regime shift in the volatility of four segmented markets and SWARCH model appears to outperform standard GARCH family models. Second, although there are some common features of volatility switch in segmented markets, there exist a few difference: (i)compared with the A-share markets, B-share markets are more volatile and shift more frequently between high- and low-volatility states; (ii) B-share markets have longer stays at high volatility state than the A-share markets; (iii) the relative magnitude of the high volatility compared with that of the low volatility is much greater than the case in two A-share markets. Third, B-share markets are found to be more sensitive to international shocks, while the A-share markets seem immune to international spillovers of volatility. Finally, analyses of volatility spillover effect among the four stock markets indicate that the A-share markets play a dominant role in volatility in Chinese stock markets.