2.1.1—Effective demand

Effective demand is the quantity of a good or service consumers are willing and able to purchase at a particular price and time. Desire alone is not demand if purchasing power or access is absent.

A demand schedule links price to quantities demanded, holding other relevant factors constant. Income, expectations, tastes and related-good prices can change demand at every price.

A student may want a laptop but becomes an effective demander only when they can pay or obtain finance at the stated price.

A social-media wish list measures desire, not necessarily effective demand; ability to pay and a chosen price matter.