“…Everyone belongs to a specific peer group; that is, the human group born in the same era and region. Many major social events, such as wars, economic depression, famines, epidemics and natural disaster have similar effects on the members of a particular peer group ( Cheng and Zhang, 2011 ; Malmendier et al, 2011 ; Cameron and Shah, 2015 ; Bernile et al, 2017 ; Cassar et al, 2017 ; Feng and Johansson, 2018 ; Choi et al, 2020 ). Psychologists define this influence effect as cohort effect, which considers that similar age groups show similar personality and behavior characteristics due to similar experience and social environment.…”