作者机构:[1]Department of statistics, Yunnan Unversity, Kunming 650091, China, [2]Faculty of Science, Kunming University of Science and Technology, Kunming 650093, China
相关基金:Supported by the National Natural Science Foundation of China (11261025, 11201412), the Natural Science Foundation of Yunnan Province (2011FB016) and the Program for Middle-aged Backbone Teacher, Yunnan University.