作者akai0928 (so what)
看板Economics
标题Re: [请益] 急~请问独占市场的弹性
时间Tue Jan 6 22:40:39 2009
注:厂商的最适决策是要追求「利润」极大化
若生产过程中,提高产量可以增加「利润」,就会增产
(不是增加收益)
因此原PO在上一篇的推文中提到
何不在无弹性的阶段生产?
因为在无弹性的阶段生产,只要增产,利润就会增加
因此厂商会增产,直到Ed > 1 的阶段
且 MR = MC 为止 (忽略充份条件的讨论)
Note that a monopolist always produces a quantity at which
demand is elastic.
(追求利润极大化) 的独占厂商,其最适产量必发生在需求弹性大於1之处
(注1:elastic:有弹性、或弹性大於1)
(注2:此处没有特别说明,但前提是需求线是线性的)
If the firm produced a quantity for which demand was inelastic,
then if the firm raised its price,quantity would fall by a smaller
percentage than the rise inprice, so revenue would increase.
若此一厂商在需求曲线上无弹性(inelastic, 弹性小於1) 的阶段进行生产
只要此一厂商提高售价,因为需求量减少的幅度 小於 价格提高的幅度
所以总收益(TR) 仍会增加
(注1:|Ed| = dlnQ / dlnP < 1 => dlnQ < dlnP
需求量变动百分比 < 价格变动百分比 )
(注2:Ed小於1时,P与TR呈同向变动:dTR / dP > 0)
Because costs would decrease at a lower quantity,
the firm would have higher revenue and lower costs,
so profit would be higher.
(承上:在需求无弹性的阶段,只要厂商抬高价格、减少产出,则)
当产量较低(少)时,成本较低,且收益(TR) 较高
因此 (在Ed小於1的阶段) 可以 (透过提高售价) 获得较高的利润
==============================================================================
Max profit = TR - TC = P(Q)*Q - TC(Q)
f.o.c
d(profit) / dQ = 0
(dTR/dQ) - (dTC/dQ) = 0
MR - MC = 0
MR = MC
又:MR = P [ 1 - (1/Ed) ],且一般设定 MC非负
MR = MC
P [ 1 - (1/Ed) ] = MC > 0
1 - (1/Ed) > 0
Ed > 1
==============================================================================
※ 引述《eu7908 (小事)》之铭言:
: 老师给的投影片上面是这样写:
: Note that a monopolist always produces a quantity at which
: demand is elastic. If the firm produced a quantity for which
: demand was inelastic, then if the firm raised its price,
: quantity would fall by a smaller percentage than the rise in
: price, so revenue would increase. Because costs would decrease
: at a lower quantity, the firm would have higher revenue and
: lower costs, so profit would be higher.
: 我不懂的是
: 明明说独占厂商总是在弹性的时候制造,那後面又说
: 若demand是非弹性的时候,提高价格,收入又会增加
: 既然如此,为什麽不在非弹性的时候制造呢?
: 後面又有说成本在较少量的时候会减少,通常不是
: 制造越多成本越低吗?
: 还是这有错误?
: 我整个雾煞煞啊T^T
: 请救救我!
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◆ From: 118.170.5.9
※ 编辑: akai0928 来自: 118.170.5.9 (01/06 22:41)
※ 编辑: akai0928 来自: 118.170.5.9 (01/06 22:47)
※ 编辑: akai0928 来自: 118.170.5.9 (01/06 22:49)
1F:推 blizzardsun:是减产还是增产? 118.166.78.139 01/07 22:10
2F:推 moniya:弹性小於1必定要减产才有利润 58.115.27.142 01/10 01:36
3F:→ moniya:弹性=1时,产量刚好会在MR=0的地方 58.115.27.142 01/10 01:37