“…Some studies have combined the head of household's age and marital status, presence of children, and age of children (if applicable) to represent the family life cycle. Results have shown that households' travel expenditure differs significantly across the life cycle (Bernini & Cracolici, 2015; Sun et al, 2015). In terms of the head of household's education level, most studies have reported significant positive effects (Alegre et al, 2013; Alegre & Pou, 2016; Hong, Morrison, & Cai, 1996; Sun et al, 2015; Zhang & Feng, 2018; Zheng & Zhang, 2013), although a few have found no effects at all (Haq et al, 2019).…”