Transcript Recitation_week9

經濟學原理與實習
台大經濟系
謝沛勳
1.Betty’s Bakery bakes fresh bread every morning. Any bread not sold by
the end of the day is thrown away.A loaf of bread costs Betty $2.00 to
produce, and she prices loaves of bread at $3.50 per loaf. Supposenear the
end of one day Betty still has 12 loaves of bread on hand. Which of the
following is correct?
(C)Betty should be willing to sell the remaining bread for any price above
$0 per loaf since she will have to throw it away if she does not sell it for
something.
麵包店的選擇：1.麵包賣不出去
2.賣多少算多少，加減賺
麵包的製作成本已經付出，賺不回來。選2.雖然會虧本，但仍是較好的選擇。
2種商品：食物、機器 原本的生產點(食物，機器)=(1000,47)
在機器製造的技術進步之後，有機會移動生產點到(1050,47)嗎？
生產可能曲線的假設：所有產品皆使用相同的要素。
製造機器的技術進步節省下來的要素可給食物使用
食
物
(1050,47)
(1000,47)
機器技術進步，在全部要素生產機器時可生產更多
機器
In the early 19th century, the Russian government sent doctors to southern Russian
villages to provide assistance during a cholera epidemic. The villagers noticed that
wherever doctors appeared, people died. Therefore, many doctors were chased away
from villages, and some were even killed. This reaction to the correlation between
doctors and deaths is most likely a problem of
(b) reverse causality.
Canada and the U.S. both produce wheat and computer software. Canada is said to have
the comparative advantage in producing wheat if
(b) the opportunity cost of producing a bushel of wheat is lower for Canada than it is for
the U.S.
比較利益指的是製造一項產品所需犧牲的其他產品較少，並非所需
成本較少。
每個人都有”相對”擅長的事情天生我才必有用
Suppose an increase in the price of rubber coincides with an advance in the technology
of tire production. As a result of these two events, the demand for tires
(d) None of the above is necessarily correct.
此題未能知道供給曲線的移動方向
Pens are normal goods. What will happen to the equilibrium price of pens if the price of
pencils rises, consumers experience an increase in income, writing in ink becomes
fashionable, people expect the price of pens to rise in the near future, the population
increases, fewer firms manufacture pens, and the wages of pen-makers increase?
(a) Price will rise.
the price of pencils rises替代品價格上漲
consumers experience an increase in income
writing in ink becomes fashionable互補品需求增加
people expect the price of pens to rise in the near future
the population increases
fewer firms manufacture pens
the wages of pen-makers increase
需求增加
供給減少
For a particular good, a 2 percent increase in price causes a 12 percent decrease in quantity
demanded.
Which of the following statements is most likely applicable to this good?
(b) The good is a luxury.
彈性大於一
替代品很多
奢侈品
市場定義狹隘
在長期之下
Suppose that when the price of wheat is $2 per bushel, farmers can sell 10 million bushels.
When the price of wheat is $3 per bushel, farmers can sell 8 million bushels. Which of the
following statements is true? The demand for wheat is
(c) price inelastic, so an increase in the price of wheat will increase the total revenue of
wheat farmers.
8 − 10 3 + 2
5
×
=−
3 − 2 8 + 10
9
Total Revenue=P × Q
Q的下降百分比較P的上漲百分比小
Total Revenue增加
Suppose there is currently a tax of $50 per ticket on airline tickets. Sellers of airline tickets
are required to pay the tax to the government. If the tax is reduced from $50 per ticket to
$30 per ticket, then the
(c) supply curve will shift downward by $20, and the effective price received by sellers will
increase by less than $20.
If the government removes a binding price floor from a market, then the price received by
sellers will
(b) decrease, and the quantity sold in the market will increase.
Steak and chicken are substitutes. A sharp reduction in the supply of steak would
(c) decrease consumer surplus in the market for steak and increase producer surplus
in the market for
chicken.
Kate is a personal trainer whose client William pays $80 per hour-long session. William
values this service at $100 per hour, while the opportunity cost of Kate’s time is $75 per
hour. The government places a tax of $10 per hour on personal trainers. After the tax,
what is likely to happen in the market for personal training?
(a) Kate and William will agree to a new price somewhere between $85 and $100.
Kate不願意收少於$75，William不願意付超過$100。
價差$25，稅$10
故雙方仍會達成交易
Suppose a country begins to allow international trade in steel. Which of the following
outcomes will be observed regardless of whether the country finds itself importing steel
or exporting steel?
(a) The sum of consumer surplus and producer surplus for domestic traders of steel
increases.
總剩餘會增加
The before-trade price of fish in Denmark is $10.00 per pound. The world price of fish is
$6.00 per pound. Denmark is a price-taker in the fish market. If Denmark begins to allow
trade in fish, its consumers of fish will become
(d) better off, its producers of fish will become worse off, and on balance the citizens of
Denmark will become better off.
前
後
Suppose that Charles wants to dine at a fancy restaurant, but the only available table is in
the smoking section. Charles dislikes the smell of cigarette smoke. He notices that only
one person, Sam, is smoking in the smoking section. Charles values the absence of smoke
at $40. Sam values the ability to smoke in the restaurant at $15. Which of the following
represents an efficient solution in the absence of transaction costs?
(b) Charles offers Sam between $15 and $40 not to smoke. Sam accepts, and both parties
are better off.
Charles最多願意付$40讓Sam不抽菸，Sam收$15就願意不抽菸
Deal
1.(a)為什麼生產可能曲線會凹向原點，請解釋並試舉一例。又何時
生產可能曲線是直線？
在機會成本遞增時生產可能曲線會凹向原點。在台灣平地適合生產
稻米，而丘陵地適合生產茶葉。一開始種茶時，會先從丘陵地開始
種，此時犧牲的稻米產量很少。但隨著茶葉種植面積的上升，會在
更適合稻米生產的土地種植茶葉，此時生產相同數量的茶葉就必須
犧牲更多的稻米。
在機會成本不變時生產可能曲線是直線。
1.(b)請由供給面和需求面解釋為何各國等候器官供給的人越來越
多？
關鍵：等候，表示供不應求
原因是交易器官不合法，交易價格上限為0
1.(c)
成本完全轉嫁給勞工，表示勞工彈性較小
2.台大的牛奶在目前的價格下供不應求，當牛奶貨到前總是出現大批排隊人潮，
還引起不少紛爭。台大農產品中心為了消除此一現象，想了兩種方式：(1)在目
前價格之下，想買的人抽籤決定誰買的到(2)調高售價至供需均衡，
(a)試以圖形分析兩種方式的生產者剩餘、消費者剩餘、總剩餘，並分析哪種方
式總剩餘較高。
(b)時間成本較低，願付時間較高的人較可能買到
(c)除非老人是願付價格高的人，否則不效率
南一中共有2500名學生，學校規定每位學生至少要買一件制服。假設南一中制
服跟其他學校制服是完全不同的商品，在制服價格大於$100時南一中學生不會
想多買幾件備用，制服的供給曲線為Q=10P。
(a)
這塊是新增的消費
者剩餘，
也是政府補貼
(a)
(b)
(d )
生產可能曲線二三事
經濟學旨在研究效用極大化之行為
不只人類，眾生皆如此
生產可能曲線二三事
• Q:你確定每個人都會計算如何效用極大化嗎？為何這麼多人做蠢事
• A:思考也需要成本，你覺得你做蠢事的代價比你思考的成本低，做蠢
事也是很合理滴
器官捐贈二三事
器官捐贈二三事
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