What is negative income elacsticty of demand?

Negative income elasticity of demand refers to a situation where the quantity demanded of a good decreases as consumer income increases. This typically applies to inferior goods, which are items that people tend to buy less of when they can afford better alternatives. For example, as consumers' incomes rise, they may choose to buy less generic brand food in favor of premium brands. In this case, the income elasticity of demand would be negative, indicating an inverse relationship between income and demand.