ACKNOWLEDGEMENT
The first author, Lu Xixi, would like to express his sincere thanks to Professor Des Walling for his support, encouragements and inspirations over many years. This study was supported by the National University of Singapore (R‐109‐000‐227‐115) and the Yunnan University of Finance and Economics. The work was also supported by the studentship awarded to Boey Lai Hsia from the Yunnan University of Finance and Economics. We want to thank Professor Zhou Yue, Yunnan University of Finance and Economics, for his support to our work in Yunnan. We also want to thank Professor Bruce Webb for his invitation and editing the special issue.