“…Total consumption expenditures, used in several studies to proxy income (Dardis et aL, 1981;Nelson, 1989;Wagner and Hanna, 1983), provide a better fit in models built for prediction purposes (Dardis et al, 1981). The magnitude of expenditure elasticities tends to be greater than unity (Dardis et al, 1981;Nelson, 1989), whereas the magnitude of income elasticities tends to be less than unity (Dardis et al, 1981;Norum, 1989;Zhang and Norton, 1995). In addition to the income measure, a variety of socioeconomic and demographic factors, such as age, family size, education, occupation, and region, were included in the analyses.…”