There are many factors that can directly affect supply and demand and indirectly affect price and quantity. In the first column we identify a change in a given factor. How does the change in the factor affect supply or demand? How does it affect price and quantity? Draw an upward arrow () in the demand column if demand rises and a downward arrow () if demand falls. The same holds for supply, equilibrium price, and equilibrium quantity.

Factor	Demand	Supply	Equilibrium Price	Equilibrium Quantity
Price of a substitute rises
Price of a compliment falls
Income rises (normal good)
Income falls (inferior good)
Price of relavant resource rises
Technology advances
Quota
Number of buyers rises
Number of sellers rises
Buyers expect higher price
Sellers expect higher price
Tax on production
Preferences become more favorable with respect to the good