Giffen Good

A Giffen good is a low income, non-luxury product that defies standard economic and consumer demand theory. Demand for Giffen goods rises when the price rises and falls when the price falls. In econometrics, this results in an upward-sloping demand curve, contrary to the fundamental laws of demand which create a downward sloping demand curve.1

The term “Giffen goods” was coined in the late 1800s, named after noted Scottish economist, statistician, and journalist Sir Robert Giffen. The concept of Giffen goods focuses on a low income, non-luxury products that have very few close substitutes. Giffen goods can be compared to Veblen goods which similarly defy standard economic and consumer demand theory but focus on luxury goods.

Examples of Giffen goods can include bread, rice, and wheat. These goods are commonly essentials with few near-dimensional substitutes at the same price levels.

Giffen goods are a rarity in economics because supply and demand for these goods are opposite of standard conventions. Giffen goods can be the result of multiple market variables including supply, demand, price, income, and substitution. All of these variables are central to the basic theories of supply and demand economics. Examples of Giffen goods are a study in the effects of these variables on low-income, non-luxury goods which result in an upward sloping demand curve.

The laws of supply and demand govern macro and microeconomic theories. Economists have found that when prices rise, demand falls creating a downward sloping curve. When prices fall, demand is expected to increase creating an upward sloping curve. Income can slightly mitigate these results, flattening curves since more personal income can result in different behaviors. Substitution and the substitution effect can also be significant. Since there are typically substitutes for most goods, the substitution effect helps strengthen the case for standard supply and demand. In the case of Giffen goods, the income effect can be substantial while the substitution effect is also impactful. With Giffen goods, the demand curve is upward sloping which shows more demand at higher prices. Since there are few substitutes for Giffen goods, consumers continue to remain willing to buy a Giffen good when the price rises.

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