Her father is Robert Ellis Silberstein (Jewish). Her mother is Diana Ross (African-American).
If the cross price elasticity is positive, then we call such goods Substitutes (example: pizza and burgers -- you usually consume either or). The income elasticity of demand measures the change in the quantity demanded of some good, when the income changes, holding everything else constant.For example you can measure what happens to the demand for expensive red wine when income increases.f the cross price elasticity is positive, then we call such goods Substitutes (example: pizza and burgers -- you usually consume either or). The income elasticity of demand measures the change in the quantity demanded of some good, when the income changes, holding everything else constant.
1 A positive income elasticity of demand is associated with normal goods; an increase in income will lead to a rise in demand. 2  If income elasticity of demand of a commodity is less than 1, it is a necessity good.3  If the elasticity of demand is greater than 1, it is a luxury good or a superior good.nitary income elasticity of demand: In this case increase in income is accompanied by same proportionate increase in quantity demanded. Here the value of coefficient Ey is equal to unity (Ey=1). E.g.: 10% increase in quantity demanded due to 10% increase in income.