課程名稱︰個體經濟學
課程性質︰必修
課程教師︰黃景沂
開課學院：社會科學院
開課系所︰經濟學系
考試日期（年月日）︰100/11/14
考試時限（分鐘）：180分鐘
是否需發放獎勵金：是
（如未明確表示，則不予發放）
試題 :
You have to provide explanations for all of your answers.
1. Anne's utility on milk (X) and juice (Y) can be expressed as
u(x,y) = √x ＋ 2 √y.
(a) (5%) Suppose that Anne spends I dollars on milk and juice every month.
The price of milk is Px, and the price of juice is Py. How much milk
does she consume in a month? (express your answer as a function of Px,
Py,and I)
(b) (5%) Suppose that Px=1, Py=1 and I=10. Use your answer in part (a) to
compute Anne's price elasticity of demand for milk.
(c) (5%) Suppose that Px=1, Py=1 and I=10. Use your answer in part (a) to
compute Anne's income elasticity of demand for milk.
(d) (5%) Suppose that Px=1, Py=1 and I=10. Use your answer in part (a) to
compute Anne's cross elasticity of demand for milk. Are milk and juice
substitutes or complements for Anne?
2. Bruce's utility on milk (X) and juice (Y) can be expressed as u(x,y)= x+y.
Suppose that Bruce spends 1000 dollars on milk and juice every month. The
price of milk increases from $15 to $25. However, the price of juice is
fixed at $20.
(a) (10%) How much milk does he consume in a month before the price increase?
How much milk does he consume in a month after the price increase?
(b) (10%) How much of the change in his milk consumption is due to the
substitution effect? How much of the change in his milk consumption is
due to the income effect? (Please use Hicks' definition to decompose
the effects.)
3. (10%) Consider th following two policiees: (a) giving everyone a NT$3,600
consumption voucher (消費券) ; (b) reducing tax rate on everyone's wage
income by 10%. Suppose you have well-behaved preference with strict
convexity, and you like these two policies equally. Will policy (b) reduces
your tax payment by more than NT$3,600 or less than NT$3,600?
4. (15%) We say that a consumer has a well-behaved preferences if his/her
preference is complete, transitive, monotonic, and convex. We observe the
consumption behaviors of Cindy, David, and Eddy in two different months:
September and October. Suppose they only consume two goods X and Y. Their
tastes do not change in these two months, but the prices of X and Y differ
over time. Can you tell who does not have a well-behaved preference?
Explain your answer.
---------------------------------------------------------------------
September October
---------------------------------------------------------------------
Price (Px,Py) (2,3) (3,4)
---------------------------------------------------------------------
Cindy's choice (Xa,Ya) (10,19) (35,5)
David's choice (Xb,Yb) (25,15) (10,26)
Eddy's choice (Xc,Yc) (11,20) (25,10)
=====================================================================
5. (15%) Coffee currently sells for $50 per cup. Suppose that the government
simultaneously institutes an excise tax of $10 per cup and a sales subsidy
of $10 per cup. (The "sales subsidy" means that every time you buy a cup of
coffee, you get $10 from the government.) What is the new market price of
coffee? Are demanders helped or hurt by this pair of policies? What about
suppliers?
6. (10%) Why is the substitution effect always negative for a consumer with
well-behaved preference when the price of a produce increases?
7. Suppose the amount of time required for Fay and Grace to bake one unit of
cake or pizza is given by the following table:
-------------------------------
cake pizza
-------------------------------
Fay 5 hours 6 hours
Grace 3 hours 4 hours
===============================
If an individual bakes x units of these foods, the required time is x
multiplies the values given in the above table. For simplicity, we will
allow x to be a non-integer mumber.
(a) (5%) Who has the comparative advantage at cake? At pizza?
(b) (5%) Suppose the two persons can trade. The exchange rate for one unit
of cake is x units of pizza. Find out all possible values of x such
that both persons can benefit from trade.
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 140.112.220.171