Lecture # 8
Market Demand: The sum of individual demands
• Market demand curve add up all the horizontal quantity of the good, not vertical.
• Shift in demand (change in demand curve) to the left or the right are caused by a change
in anything other than the price of the good.
• Movement along the demand curve (change in the quantity demanded) is caused by a
change in price.
o If demand increases, the curve shifts out (right).
o If the demand decreases, the curve shifts in (left).
• Quantity Supplied (Q ): The amount of a good that sellers are willing and able to sell.
• The variables that influence how much sellers want to sell are: