of;
Statistics;
and;
Financial;
Mathematics,;
School;
of;
Mathematical;
Sciences,;
Beijing;
Normal;
University,;
Beijing;
100875,;
China;
of;
Statistics,;
School;
of;
Mathematical;
Sciences,;
Capital;
Normal;
University,;
Beijing;
100048,;
China;
of;
Statistics,;
The;
Pennsylvania;
State;
University,;
University;
Park,;
PA;
16802,;
USA;