曼昆经济学原理04供给需求及市场力量课件.ppt

The Market Forces of Supply and DemandChapter 4曼昆经济学原理04-供给需求及市场力量The Market Forces of Supply and DemanduSupply and demand are the two words that economists use most often.uSupply and demand are the forces that make market economies work.uModern microeconomics is about supply, demand, and market equilibrium.曼昆经济学原理04-供给需求及市场力量Markets uA market is a group of buyers and sellers of a particular good or service. uThe terms supply and demand refer to the behavior of people . . . as they interact with one another in markets. 曼昆经济学原理04-供给需求及市场力量Markets u Buyers determine demand.u Sellers determine supply.曼昆经济学原理04-供给需求及市场力量Market Type: A Competitive MarketA competitive market is a market. . .¼with many buyers and sellers.¼that is not controlled by any one person.¼in which a narrow range of prices are established that buyers and sellers act upon.曼昆经济学原理04-供给需求及市场力量Competition: Perfect and OtherwiseuProducts are the sameuNumerous buyers and sellers so that each has no influence over priceuBuyers and Sellers are price takersPerfect Competition曼昆经济学原理04-供给需求及市场力量Competition: Perfect and OtherwiseuMonopolyuOne seller, and seller controls priceuOligopolyuFew sellersuNot always aggressive competition曼昆经济学原理04-供给需求及市场力量Competition: Perfect and OtherwiseMonopolistic CompetitionMany sellersSlightly differentiated productsEach seller may set price for its own product曼昆经济学原理04-供给需求及市场力量DemandQuantity demanded is the amount of a good that buyers are willing and able to purchase.曼昆经济学原理04-供给需求及市场力量Law of DemandThe law of demand states that there is an inverse relationship between price and quantity demanded.曼昆经济学原理04-供给需求及市场力量Demand ScheduleThe demand schedule is a table that shows the relationship between the price of the good and the quantity demanded. 曼昆经济学原理04-供给需求及市场力量Demand Schedule曼昆经济学原理04-供给需求及市场力量Determinants of DemanduMarket priceuConsumer incomeuPrices of related goodsuTastesuExpectations曼昆经济学原理04-供给需求及市场力量Demand CurveThe demand curve is the downward-sloping line relating price to quantity demanded. 曼昆经济学原理04-供给需求及市场力量Demand Curve$3.002.502.001.501.000.502134 56789 101211Price of Ice-Cream ConeQuantity of Ice-Cream Cones0曼昆经济学原理04-供给需求及市场力量Ceteris ParibusCeteris 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!曼昆经济学原理04-供给需求及市场力量Market DemanduMarket demand refers to the sum of all individual demands for a particular good or service.uGraphically, individual demand curves are summed horizontally to obtain the market demand curve.曼昆经济学原理04-供给需求及市场力量Determinants of DemanduMarket priceuConsumer incomeuPrices of related goodsuTastesuExpectations曼昆经济学原理04-供给需求及市场力量Change in Quantity Demanded versus Change in DemandChange in Quantity DemandeduMovement along the demand curve.uCaused by a change in the price of the product.曼昆经济学原理04-供给需求及市场力量Changes in Quantity Demanded0D1Price of Cigarettes per PackNumber of Cigarettes Smoked per DayA tax that raises the price of cigarettes results in a movement along the demand curve.AC202.00$4.0012曼昆经济学原理04-供给需求及市场力量Change in Quantity Demanded versus Change in DemandChange in DemanduA shift in the demand curve, either to the left or right.uCaused by a change in a determinant other than the price.曼昆经济学原理04-供给需求及市场力量Changes in Demand0D1Price of Ice-Cream ConeQuantity of Ice-Cream ConesD3D2Increase in demandDecrease in demand曼昆经济学原理04-供给需求及市场力量Consumer IncomeuAs income increases the demand for a normal good will increase.uAs income increases the demand for an inferior good will decrease.曼昆经济学原理04-供给需求及市场力量Consumer IncomeNormal Good$3.002.502.001.501.000.502134 56789 101211Price of Ice-Cream ConeQuantity of Ice-Cream Cones0Increasein demandAn increase in income...D1D2曼昆经济学原理04-供给需求及市场力量Consumer IncomeInferior Good$3.002.502.001.501.000.502134 56789 101211Price of Ice-Cream ConeQuantity of Ice-Cream Cones0Decreasein demandAn increase in income...D1D2曼昆经济学原理04-供给需求及市场力量Prices of Related GoodsSubstitutes & ComplementsuWhen a fall in the price of one good reduces the demand for another good, the two goods are called substitutes.uWhen a fall in the price of one good increases the demand for another good, the two goods are called complements.曼昆经济学原理04-供给需求及市场力量Change in Quantity Demanded versus Change in DemandVariables that Affect Quantity DemandedA Change in This Variable . . .PriceRepresents a movementalong the demand curveIncomeShifts the demand curvePrices of relatedgoodsShifts the demand curveTastesShifts the demand curveExpectationsShifts the demand curveNumber ofbuyersShifts the demand curve曼昆经济学原理04-供给需求及市场力量SupplyQuantity supplied is the amount of a good that sellers are willing and able to sell. 曼昆经济学原理04-供给需求及市场力量Law of SupplyThe law of supply states that there is a direct (positive) relationship between price and quantity supplied.曼昆经济学原理04-供给需求及市场力量Determinants of SupplyuMarket priceuInput pricesuTechnologyuExpectations uNumber of producers曼昆经济学原理04-供给需求及市场力量Supply ScheduleThe supply schedule is a table that shows the relationship between the price of the good and the quantity supplied. 曼昆经济学原理04-供给需求及市场力量Supply Schedule曼昆经济学原理04-供给需求及市场力量Supply CurveThe supply curve is the upward-sloping line relating price to quantity supplied. 曼昆经济学原理04-供给需求及市场力量Supply Curve$3.002.502.001.501.000.5021345 6789 101211Price of Ice-Cream ConeQuantity of Ice-Cream Cones0曼昆经济学原理04-供给需求及市场力量Market SupplyuMarket supply refers to the sum of all individual supplies for all sellers of a particular good or service.uGraphically, individual supply curves are summed horizontally to obtain the market supply curve.曼昆经济学原理04-供给需求及市场力量Determinants of SupplyuMarket priceuInput pricesuTechnologyuExpectations uNumber of producers曼昆经济学原理04-供给需求及市场力量Change in Quantity Supplied versus Change in SupplyChange in Quantity SupplieduMovement along the supply curve.uCaused by a change in the market price of the product.曼昆经济学原理04-供给需求及市场力量Change in Quantity Supplied1 5Price of Ice-Cream ConeQuantity of Ice-Cream Cones0S 1.00AC$3.00A rise in the price of ice cream cones results in a movement along the supply curve.曼昆经济学原理04-供给需求及市场力量Change in Quantity Supplied versus Change in SupplyChange in SupplyuA shift in the supply curve, either to the left or right. uCaused by a change in a determinant other than price.曼昆经济学原理04-供给需求及市场力量Change in SupplyPrice of Ice-Cream ConeQuantity of Ice-Cream Cones0S1S2S3Increase in SupplyDecrease in Supply曼昆经济学原理04-供给需求及市场力量Change in Quantity Supplied versus Change in Supply曼昆经济学原理04-供给需求及市场力量Supply and Demand TogetherEquilibrium PriceuThe price that balances supply and demand. On a graph, it is the price at which the supply and demand curves intersect.Equilibrium QuantityuThe quantity that balances supply and demand. On a graph it is the quantity at which the supply and demand curves intersect. 曼昆经济学原理04-供给需求及市场力量Supply and Demand TogetherDemand ScheduleSupply ScheduleAt $2.00, the quantity demanded is equal to the quantity supplied!曼昆经济学原理04-供给需求及市场力量SupplyDemandPrice of Ice-Cream ConeQuantity of Ice-Cream ConesEquilibrium of Supply and Demand21345 6789 1012110$3.002.502.001.501.000.50Equilibrium曼昆经济学原理04-供给需求及市场力量Price of Ice-Cream ConeQuantity of Ice-Cream Cones21345 678 9 1012110$3.002.502.001.501.000.50SupplyDemandSurplusExcess Supply曼昆经济学原理04-供给需求及市场力量SurplusWhen 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.曼昆经济学原理04-供给需求及市场力量Excess DemandQuantity ofIce-Cream ConesPrice ofIce-CreamCone$2.000123456789 10 11 12 13SupplyDemand$1.50Shortage曼昆经济学原理04-供给需求及市场力量ShortageWhen 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.曼昆经济学原理04-供给需求及市场力量Three Steps To Analyzing Changes in EquilibriumuDecide whether the event shifts the supply or demand curve (or both).uDecide whether the curve(s) shift(s) to the left or to the right.uExamine how the shift affects equilibrium price and quantity.曼昆经济学原理04-供给需求及市场力量How an Increase in Demand Affects the EquilibriumPrice ofIce-CreamCone2.0007Quantity ofIce-Cream ConesSupplyInitialequilibriumD11. Hot weather increasesthe demand for ice cream...D22. ...resultingin a higherprice...$2.50103. ...and a higherquantity sold.New equilibriumHarcourt, Inc. items and derived items copyright © 2001 by Harcourt, Inc.曼昆经济学原理04-供给需求及市场力量Shifts in Curves versus Movements along CurvesuA shift in the supply curve is called a change in supply.uA movement along a fixed supply curve is called a change in quantity supplied.uA shift in the demand curve is called a change in demand.uA movement along a fixed demand curve is called a change in quantity demanded.曼昆经济学原理04-供给需求及市场力量S2How a Decrease in Supply Affects the EquilibriumPrice ofIce-CreamCone2.000123478 911 12Quantity ofIce-Cream Cones13DemandInitial equilibriumS1101. An earthquake reducesthe supply of ice cream...Newequilibrium2. ...resultingin a higherprice...$2.503. ...and a lowerquantity sold.曼昆经济学原理04-供给需求及市场力量What Happens to Price and Quantity When Supply or Demand Shifts?曼昆经济学原理04-供给需求及市场力量SummaryuEconomists use the model of supply and demand to analyze competitive markets.uThe demand curve shows how the quantity of a good depends upon the price.曼昆经济学原理04-供给需求及市场力量SummaryuAccording to the law of demand, as the price of a good rises, the quantity demanded falls.uIn addition to price, other determinants of quantity demanded include income, tastes, expectations, and the prices of complements and substitutes.曼昆经济学原理04-供给需求及市场力量SummaryuThe supply curve shows how the quantity of a good supplied depends upon the price.uAccording to the law of supply, as the price of a good rises, the quantity supplied rises.曼昆经济学原理04-供给需求及市场力量SummaryuIn addition to price, other determinants of quantity supplied include input prices, technology, and expectations.uMarket equilibrium is determined by the intersection of the supply and demand curves.曼昆经济学原理04-供给需求及市场力量SummaryuSupply and demand together determine the prices of the economy’s goods and services.uIn market economies, prices are the signals that guide the allocation of resources.曼昆经济学原理04-供给需求及市场力量Graphical Review曼昆经济学原理04-供给需求及市场力量How an Increase in Demand Affects the EquilibriumPrice ofIce-CreamCone2.000710Quantity ofIce-Cream ConesSupplyInitialequilibriumD1曼昆经济学原理04-供给需求及市场力量How an Increase in Demand Affects the EquilibriumPrice ofIce-CreamCone2.000710Quantity ofIce-Cream ConesSupplyInitialequilibriumD11. Hot weather increasesthe demand for ice cream...曼昆经济学原理04-供给需求及市场力量How an Increase in Demand Affects the EquilibriumPrice ofIce-CreamCone2.000710Quantity ofIce-Cream ConesSupplyInitialequilibriumD11. Hot weather increasesthe demand for ice cream...D2New equilibrium$2.50曼昆经济学原理04-供给需求及市场力量How an Increase in Demand Affects the EquilibriumPrice ofIce-CreamCone2.000710Quantity ofIce-Cream ConesSupplyInitialequilibriumD11. Hot weather increasesthe demand for ice cream...D2New equilibrium2. ...resultingin a higherprice...$2.50曼昆经济学原理04-供给需求及市场力量How an Increase in Demand Affects the EquilibriumPrice ofIce-CreamCone2.000710Quantity ofIce-Cream ConesSupplyInitialequilibriumD11. Hot weather increasesthe demand for ice cream...D2New equilibrium2. ...resultingin a higherprice...$2.503. ...and a higherquantity sold.Harcourt, Inc. items and derived items copyright © 2001 by Harcourt, Inc.曼昆经济学原理04-供给需求及市场力量How an Increase in Demand Affects the EquilibriumPrice ofIce-CreamCone2.000710Quantity ofIce-Cream ConesSupplyInitialequilibriumD11. Hot weather increasesthe demand for ice cream...D2New equilibrium2. ...resultingin a higherprice...$2.503. ...and a higherquantity sold.Harcourt, Inc. items and derived items copyright © 2001 by Harcourt, Inc.曼昆经济学原理04-供给需求及市场力量How a Decrease in Supply Affects the EquilibriumPrice ofIce-CreamCone2.00012345678 911 12Quantity ofIce-Cream Cones13DemandInitial equilibriumS110曼昆经济学原理04-供给需求及市场力量How a Decrease in Supply Affects the EquilibriumPrice ofIce-CreamCone2.00012345678 911 12Quantity ofIce-Cream Cones13DemandInitial equilibriumS1101. An earthquake reducesthe supply of ice cream...曼昆经济学原理04-供给需求及市场力量How a Decrease in Supply Affects the EquilibriumPrice ofIce-CreamCone2.00012345678 911 12Quantity ofIce-Cream Cones13DemandInitial equilibriumS1101. An earthquake reducesthe supply of ice cream...曼昆经济学原理04-供给需求及市场力量How a Decrease in Supply Affects the EquilibriumPrice ofIce-CreamCone2.00012345678 911 12Quantity ofIce-Cream Cones13DemandInitial equilibriumS1101. An earthquake reducesthe supply of ice cream...Newequilibrium$2.50曼昆经济学原理04-供给需求及市场力量How a Decrease in Supply Affects the EquilibriumPrice ofIce-CreamCone2.00012345678 911 12Quantity ofIce-Cream Cones13DemandInitial equilibriumS1101. An earthquake reducesthe supply of ice cream...Newequilibrium$2.502. ...resultingin a higherprice...曼昆经济学原理04-供给需求及市场力量How a Decrease in Supply Affects the EquilibriumPrice ofIce-CreamCone2.000123478 911 12Quantity ofIce-Cream Cones13DemandInitial equilibriumS1101. An earthquake reducesthe supply of ice cream...Newequilibrium$2.502. ...resultingin a higherprice...3. ...and a lowerquantity sold.曼昆经济学原理04-供给需求及市场力量。