Change Quantity Demand
CHANGE IN QUANTITY DEMANDED:
A movement along a given demand curve caused by a change in demand price. The only factor that can cause a change in quantity demanded is price. A related, but distinct, concept is a change in demand.
A change in quantity demanded is a change in the specific quantity of a good that buyers are willing and able to buy. This change in quantity demanded is caused by a change in the demand price. It is illustrated by a movement along a given demand curve.
In fact, the only way to induce a change in quantity demanded is with a change in the price. Anything else, everything else, causes a change in demand.
As the demand price induces a change in the quantity demanded and a movement along the demand curve, the five demand determinants (buyers' income, buyers' preferences, other prices, buyers' expectations, and number of buyers) remain unchanged.
Demand and Quantity Demanded
To set the stage for an understanding of this difference, take note of two related concepts: * Quantity Demanded: Quantity demand is a specific quantity that buyers are willing and able to buy at a specific demand price. It is but ONE point on a demand curve.
* Demand: Demand is the range of quantities that buyers are willing and able to buy at a range of demand prices. It is ALL points that make up a demand curve.
Making Changes
So what happens when the phrase "change in" is placed in front of each term? * Change in Quantity Demanded: A change in quantity demanded is a change from one price-quantity pair on an existing demand curve to a new price-quantity pair on the SAME demand curve. In other words, this is a movement along the demand curve. A change in quantity demanded is caused by a change in price.
* Change in Demand: A change in demand is a change in the ENTIRE demand relation. This means changing, moving, and shifting the entire demand curve. The entire set of prices and quantities is changing. In other words, this is a shift of the
A movement along a given demand curve caused by a change in demand price. The only factor that can cause a change in quantity demanded is price. A related, but distinct, concept is a change in demand.
A change in quantity demanded is a change in the specific quantity of a good that buyers are willing and able to buy. This change in quantity demanded is caused by a change in the demand price. It is illustrated by a movement along a given demand curve.
In fact, the only way to induce a change in quantity demanded is with a change in the price. Anything else, everything else, causes a change in demand.
As the demand price induces a change in the quantity demanded and a movement along the demand curve, the five demand determinants (buyers' income, buyers' preferences, other prices, buyers' expectations, and number of buyers) remain unchanged.
Demand and Quantity Demanded
To set the stage for an understanding of this difference, take note of two related concepts: * Quantity Demanded: Quantity demand is a specific quantity that buyers are willing and able to buy at a specific demand price. It is but ONE point on a demand curve.
* Demand: Demand is the range of quantities that buyers are willing and able to buy at a range of demand prices. It is ALL points that make up a demand curve.
Making Changes
So what happens when the phrase "change in" is placed in front of each term? * Change in Quantity Demanded: A change in quantity demanded is a change from one price-quantity pair on an existing demand curve to a new price-quantity pair on the SAME demand curve. In other words, this is a movement along the demand curve. A change in quantity demanded is caused by a change in price.
* Change in Demand: A change in demand is a change in the ENTIRE demand relation. This means changing, moving, and shifting the entire demand curve. The entire set of prices and quantities is changing. In other words, this is a shift of the