Four Q parameters of the initial sample, with Q1 and Q2 defined by Messineo et al. (2012), Q3 and Q4 defined by us. The RSG population appears to be in a separate branch between foreground dwarfs and AGBs inthe bright end. Due to the relativelow sensitivity and the small number of sample crossmatched with the APOGEE survey inXue et al. (2016), the Q4 parameter defined here is onlyused as a reference.