曼昆哈佛大学经济学原理第四章.pptx

Click to edit Master title style,Click to edit Master text styles,Second Level,Third Level,Fourth Level,Fifth Level,Harcourt,Inc.items and derived items copyright 2001 by Harcourt,Inc.,The Market Forces of Supply and Demand,Chapter 4,Copyright 2023 by Harcourt,Inc,.All rights reserved.Requests for permission to make copies of any part of thework should be mailed to:,Permissions Department,Harcourt College Publishers,6277 Sea Harbor Drive,Orlando,Florida 32887-6777.,The Market Forces of Supply and Demand,Supply,and,demand,are the two words that economists use most often.,Supply,and,demand,are the forces that make market economies work.,Modern microeconomics is about supply,demand,and market equilibrium.,Markets,A,market,is a group of buyers and sellers of a particular good or service.,The terms supply and demand refer to the behavior of people.as they interact with one another in,markets,.,Markets,Buyers,determine,demand,.,Sellers,determine,supply,.,Market Type:,A Competitive Market,A,competitive market,is a market.,with,many,buyers and sellers.,that is not controlled by any one person.,in which a,narrow range of prices,are established that buyers and sellers act upon.,CompetitionPerfect and Otherwise,Products are the same,Numerous buyers and sellers so that each has no influence over price,Buyers and Sellers are price takers,Perfect Competition,Competition:,Perfect and Otherwise,Monopoly,One seller,and seller controls price,Oligopoly,Few sellers,Not always aggressive competition,Competition:,Perfect and Otherwise,Monopolistic Competition,Many sellers,Slightly differentiated products,Each seller may set price for its own product,Demand,Quantity demanded,is the amount of a good that buyers are,willing and able,to purchase.,Law of Demand,The,law of demand,states that there is an,inverse relationship,between price and quantity demanded.,Demand Schedule,The,demand schedule,is a table that shows the relationship between the,price,of the good and the,quantity,demanded.,Demand Schedule,Determinants of Demand,Market price,Consumer income,Prices of related goods,Tastes,Expectations,Demand Curve,The,demand curve,is,the downward-sloping line relating price to quantity demanded.,Demand Curve,$3.00,2.50,2.00,1.50,1.00,0.50,2,1,3,4,5,6,7,8,9,10,12,11,Price of Ice-Cream Cone,Quantity of Ice-Cream Cones,0,Ceteris Paribus,Ceteris paribus,is a Latin phrase that means all variables other than the ones being studied are assumed to be constant.Literally,ceteris paribus,means“other things being equal.”,The demand curve slopes downward because,ceteris paribus,lower prices imply a greater quantity demanded!,Market Demand,Market demand,refers to the sum of all individual demands for a particular good or service.,Graphically,individual demand curves are summed,horizontally,to obtain the market demand curve.,Determinants of Demand,Market price,Consumer income,Prices of related goods,Tastes,Expectations,Change in Quantity Demanded versus Change in Demand,Change in,Quantity Demanded,Movement along the demand curve.,Caused by a change in the,price,of the product.,Changes in Quantity Demanded,0,D,1,Price of Cigarettes per Pack,Number of Cigarettes Smoked per Day,A tax that raises the price of cigarettes results in a movement along the demand curve.,A,C,20,2.00,$4.00,12Change in Quantity Demanded versus Change in Demand,Change in,Demand,A shift in the demand curve,either to the left or right.,Caused by a change in a determinant other than the price.,Changes in Demand,0,D,1,Price of Ice-Cream Cone,Quantity of Ice-Cream Cones,D,3,D,2,Increase in demand,Decrease in demand,Consumer Income,As income increases the demand for a,normal good,will,increase,.,As income increases the demand for an,inferior good,will,decrease,.,Consumer Income,Normal Good,$3.00,2.50,2.00,1.50,1.00,0.50,2,1,3,4,5,6,7,8,9,10,12,11,Price of Ice-Cream Cone,Quantity of Ice-Cream Cones,0,Increase,in demand,An increase in income.,D,1,D,2,Consumer Income,Inferior Good,$3.00,2.50,2.00,1.50,1.00,0.50,2,1,3,4,5,6,7,8,9,10,12,11,Price of Ice-Cream Cone,Quantity of Ice-Cream Cones,0,Decrease,in demand,An increase in income.,D,1,D,2,Prices of Related Goods,Substitutes&Complements,When a fall in the price of one good reduces,the demand for another good,the two goods are called,substitutes,.,When a fall in the price of one good increases,the demand for another good,the two goods are called,complements,.,Change in Quantity Demanded versus Change in Demand,Variables that Affect Quantity Demanded,A Change in,This Variable.,Price,Represents a movement,along the demand curve,Income,Shifts the demand curve,Prices of related,goods,Shifts the demand curve,Tastes,Shifts the demand curve,Expectations,Shifts the demand curve,Number of,buyers,Shifts the demand curve,Supply,Quantity supplied,is the amount of a good that sellers are,willing and able,to sell.,Law of Supply,The,law of supply,states that there is a,direct(positive)relationship,between price and quantity,supplied.,Determinants of Supply,Market price,Input prices,Technology,Expectations,Number of producers,Supply Schedule,The,supply schedule,is,a table that shows the relationship between the price of the good and the quantity supplied.,Supply Schedule,Supply Curve,The,supply curve,is the upward-sloping line relating price to quantity supplied.,Supply Curve,$3.00,2.50,2.00,1.50,1.00,0.50,2,1,3,4,5,6,7,8,9,10,12,11,Price of Ice-Cream Cone,Quantity of Ice-Cream Cones,0,Market Supply,Market supply,refers to the sum of all individual supplies for all sellers of a particular good or service.,Graphically,individual supply curves are summed,horizontally,to obtain the market supply curve.,Determinants of Supply,Market price,Input prices,Technology,Expectations,Number of producers,Change in Quantity Supplied versus Change in Supply,Change in,Quantity Supplied,Movement along the supply curve.,Caused by a change in the market price of the product.,Change in Quantity Supplied,1,5,Price of Ice-Cream Cone,Quantity of Ice-Cream Cones,0,S,1.00,A,C,$3.00,A rise in the price of ice cream cones results in a,movement along the supply curve,.,Change in Quantity Supplied versus Change in Supply,Change in Supply,A,shift,in the supply curve,either to the left or right.,Caused by a change in a determinant other than price.,Change in Supply,Price of Ice-Cream Cone,Quantity of Ice-Cream Cones,0,S,1,S,2,S,3,Increase in Supply,Decrease in Supply,Change in Quantity Supplied versus Change in Supply,Supply and Demand Together,Equilibrium Price,The price that balances supply and demand.On a graph,it is the price at which the supply and demand curves intersect.,Equilibrium Quantity,The quantity that balances supply and demand.On a graph it is the quantity at which the supply and demand curves intersect.,Supply and Demand Together,Demand Schedule,Supply Schedule,At$2.00,the quantity demanded is equal to the quantity supplied!,Supply,Demand,Price of Ice-Cream Cone,Quantity of Ice-Cream Cones,Equilibrium of Supply and Demand,2,1,3,4,5,6,7,8,9,10,12,11,0,$3.00,2.50,2.00,1.50,1.00,0.50,Equilibrium,Price of Ice-Cream Cone,Quantity of Ice-Cream Cones,2,1,3,4,5,6,7,8,9,10,12,11,0,$3.00,2.50,2.00,1.50,1.00,0.50,Supply,Demand,SurplusExcess Supply,Surplus,When the price is,above,the equilibrium price,the quantity supplied exceeds the quantity demanded.There is,excess supply,or a,surplus.,Suppliers will lower the price to increase sales,thereby moving toward equilibrium.,Excess Demand,Quantity of,Ice-Cream Cones,Price of,Ice-Cream,Cone,$2.00,0,1,2,3,4,5,6,7,8,9,10,11,12,13,Supply,Demand,$1.50,Shortage,Shortage,When the price is,below,the equilibrium price,the quantity demanded exceeds the quantity supplied.There is,excess demand,or a,shortage.,Suppliers will raise the price due to too many buyers chasing too few goods,thereby moving toward equilibrium.,Three Steps To Analyzing Changes in Equilibrium,Decide whether the event shifts the supply or demand curve(or both).,Decide whether the curve(s)shift(s)to the left or to the right.,Examine how the shift affects equilibrium price and quantity.,How an Increase in Demand Affects the Equilibrium,Price of,Ice-Cream,Cone,2.00,0,7,Quantity of,Ice-Cream Cones,Supply,Initial,equilibrium,D,1,1.Hot weather increases,the demand for ice cream.,D,2,2.resulting,in a higher,price.,$2.50,10,3.and a higher,quantity sold.,New equilibrium,Harcourt,Inc.items and derived items copyright 2023 by Harcourt,Inc.,Shifts in Curves versus Movements along Curves,A shift in the supply curve is called a,change in supply,.,A movement along a fixed supply curve is called a,change in,quantity,supplied,.,A shift in the demand curve is called a,change in demand,.,A movement along a fixed demand curve is called a,change in,quantity,demanded,.,S,2,How a Decrease in Supply Affects the Equilibrium,Price of,Ice-Cream,Cone,2.00,0,1,2,3,4,7,8,9,11,12,Quantity of,Ice-Cream Cones,13,Demand,Initial equilibrium,S,1,10,1.An earthquake reduces,the supply of ice cream.,New,equilibrium,2.resulting,in a higher,price.,$2.50,3.and a lower,quantity sold.,What Happens to Price and Quantity When Supply or Demand Shifts?,Summary,Economists use the model of supply and demand to analyze competitive markets.,The demand curve shows how the quantity of a good depends upon the price.,Summary,According to the law of demand,as the price of a good rises,the quantity demanded falls.,In addition to price,other determinants of quantity demanded include income,tastes,expectations,and the prices of complements and substitutes.,Summary,The supply curve shows how the quantity of a good supplied depends upon the price.,According to the law of supply,as the price of a good rises,the quantity supplied rises.,Summary,In addition to price,other determinants of quantity supplied include input prices,technology,and expectations.,Market equilibrium is determined by the intersection of the supply and demand curves.,Summary,Supply and demand together determine the prices of the economys goods and services.,In market economies,prices are the signals that guide the allocation of resources.,Graphical Review,How an Increase in Demand Affects the Equilibrium,Price of,Ice-Cream,Cone,2.00,0,7,10,Quantity of,Ice-Cream Cones,Supply,Initial,equilibrium,D,1,How an Increase in Demand Affects the Equilibrium,Price of,Ice-Cream,Cone,2.00,0,7,10,Quantity of,Ice-Cream Cones,Supply,Initial,equilibrium,D,1,1.Hot weather increases,the demand for ice cream.,How an Increase in Demand Affects the Equilibrium,Price of,Ice-CreamCone,2.00,0,7,10,Quantity of,Ice-Cream Cones,Supply,Initial,equilibrium,D,1,1.Hot weather increases,the demand for ice cream.,D,2,New equilibrium,$2.50,How an Increase in Demand Affects the Equilibrium,Price of,Ice-Cream,Cone,2.00,0,7,10,Quantity of,Ice-Cream Cones,Supply,Initial,equilibrium,D,1,1.Hot weather increases,the demand for ice cream.,D,2,New equilibrium,2.resulting,in a higher,price.,$2.50,How an Increase in Demand Affects the Equilibrium,Price of,Ice-Cream,Cone,2.00,0,7,10,Quantity of,Ice-Cream Cones,Supply,Initial,equilibrium,D,1,1.Hot weather increases,the demand for ice cream.,D,2,New equilibrium,2.resulting,in a higher,price.,$2.50,3.and a higher,quantity sold.,Harcourt,Inc.items and derived items copyright 2023 by Harcourt,Inc.,How an Increase in Demand Affects the Equilibrium,Price of,Ice-Cream,Cone,2.00,0,7,10,Quantity of,Ice-Cream Cones,Supply,Initial,equilibrium,D,11.Hot weather increases,the demand for ice cream.,D,2,New equilibrium,2.resulting,in a higher,price.,$2.50,3.and a higher,quantity sold.,Harcourt,Inc.items and derived items copyright 2023 by Harcourt,Inc.,How a Decrease in Supply Affects the Equilibrium,Price of,Ice-Cream,Cone,2.00,0,1,2,3,4,5,6,78,9,11,12,Quantity of,Ice-Cream Cones,13,Demand,Initial equilibrium,S,1,10,How a Decrease in Supply Affects the Equilibrium,Price of,Ice-Cream,Cone,2.00,0,1,2,3,4,5,6,7,8,9,11,12,Quantity of,Ice-Cream Cones,13,Demand,Initial equilibrium,S,1,10,1.An earthquake reduces,the supply of ice cream.,How a Decrease in Supply Affects the Equilibrium,Price of,Ice-Cream,Cone,2.00,0,1,2,3,4,5,6,7,8,9,11,12,Quantity of,Ice-Cream Cones,13,Demand,Initial equilibrium,S,1,10,1.An earthquake reduces,the supply of ice cream.,How a Decrease in Supply Affects the Equilibrium,Price of,Ice-Cream,Cone,2.00,0,1,2,3,4,5,6,7,8,9,11,12,Quantity of,Ice-Cream Cones,13,Demand,Initial equilibrium,S,1,10,1.An earthquake reduces,the supply of ice cream.,New,equilibrium,$2.50,How a Decrease in Supply Affects the Equilibrium,Price of,Ice-Cream,Cone,2.00,0,1,2,3,4,5,6,7,8,9,11,12,Quantity of,Ice-Cream Cones,13,Demand,Initial equilibrium,S,1,10,1.An earthquake reduces,the supply of ice cream.,New,equilibrium,$2.50,2.resulting,in a higher,price.,How a Decrease in Supply Affects the Equilibrium,Price of,Ice-Cream,Cone,2.00,0,1,2,3,4,7,8,9,11,12,Quantity of,Ice-Cream Cones,13,Demand,Initial equilibrium,S,1,10,1.An earthquake reduces,the supply of ice cream.,New,equilibrium,$2.50,2.resulting,in a higher,price.,3.and a lower,quantity sold.,