電大本科西方經濟學業(yè)1參考答案小抄參考

1、專業(yè)好文檔答:完全競爭是指競爭不受任何阻礙和干擾的市場結構。 這種市場結構形成的條件主要有： 一是市場上有無數個購買者和生產者，每個人和每個廠商所面對的都是一個既定的市場價格，都是市場價格的接受者； 二是市場上的產品都是無差異的，任何一個廠商都不能通過生產有差別性的產品來控制市場價格； 三是廠商和生產要素可以自由流動，使資源能得到充分利用；四是購買者和生產者對市場信息完全了解，可以確定最佳購買量和銷售量，以一個確定的價格來出售產品，不致于造成多個價格并存現象。 完全競爭市場中，單個廠商面對的是一條具有完全彈性的水平的需求曲線d ，并且廠商的平均收益曲線ar、邊際收益曲線mr和需求曲線d 是重疊

2、的，即parmrd，都是水平形的。 完全競爭市場上，廠商短期均衡條件是邊際收益等于短期邊際成本，即mrsmc；廠商達到短期均衡時的盈虧狀況取決于均衡時價格p與短期平均成本曲線sac之間的關系：若psac則可獲超額利潤，若psac則虧損，若psac則有正常利潤；虧損狀態(tài)下，廠商繼續(xù)生產的條件是：價格大于或等于短期平均可變成本，即psavc 。完全競爭條件下，廠商短期供給曲線就是其邊際成本曲線，是一條向右上方傾斜的曲線，即短期邊際成本曲線smc上大于或等于平均可變成本曲線最低點以上的部分。 當一個行業(yè)中的所有廠商的供給量之和等于市場的需求量時，這一行業(yè)便達到短期均衡。完全競爭行業(yè)中，行業(yè)需求曲線即

3、為市場需求曲線，是一條向右下方傾斜的曲線；行業(yè)供給曲線是行業(yè)中所有廠商短期供給曲線之和，是一條向右上方傾斜的曲線。 完全競爭行業(yè)長期均衡有一個調整過程，至短期均衡的超額利潤或虧損為零，才實現長期均衡，故長期均衡條件是：mrlmclacsmcsac。完全競爭廠商的長期供給曲線是大于長期平均成本曲線lac最低點的那一段長期邊際成本曲線lmc，是一條向右上方傾斜的曲線。 完全競爭行業(yè)的長期供給曲線不是將行業(yè)內各廠商的長期供給曲線簡單相加，而是根據廠商進入或退出某一行業(yè)時，行業(yè)產量變化對生產要素價格所可能產生的影響，分三種情況：成本不變行業(yè)的長期供給曲線是一條水平曲線，表明行業(yè)可根據市場需求變化而調整

4、其產量供給，但市場價格保持在原來lac曲線最低點水平；成本遞增行業(yè)的長期供給曲線是斜率為正的曲線，表明行業(yè)根據市場供求調整其產量水平時，市場價格會隨之同方向變動；成本遞減行業(yè)的長期供給曲線是一條斜率為負的曲線，表明行業(yè)根據市場供求調整其產量時，市場價格會隨之成反方向變動。 完全壟斷是指整個行業(yè)中只有一個生產者的市場結構。 這種市場結構形成的主要條件： 一是廠商即行業(yè)，整個行業(yè)中只有一個廠商提供全行業(yè)所需要的全部產品； 二是廠商所生產的產品沒有任何替代品，不受任何競爭者的威脅； 三是其他廠商幾乎不可能進入該行業(yè)。在這些條件下，市場中完全沒有競爭的因素存在，廠商可以控制和操縱價格。這與完全競爭的含

5、義和形成條件是不同的。 完全壟斷廠商所面臨的需求曲線就是整個市場的需求曲線，是一條向右下方傾斜的曲線。廠商的平均收益曲線ar與其面臨的需求曲線d重疊，即pard；邊際收益曲線mr在平均收益曲線ar的下方，即mrar。平均收益曲線ar和需求曲線d（d）重疊，完全壟斷與完全競爭是相同的。所不同的是需求曲線d（d）的形狀，完全壟斷是向右下方傾斜線，完全競爭是水平線。邊際收益曲線mr和平均收益曲線ar的關系也不同，完全壟斷mrar，完全競爭mrar。 完全壟斷市場上，廠商短期均衡條件為邊際收益等于短期邊際成本，即mrsmc，這與完全競爭短期均衡條件相同。在實現均衡時，廠商大多數情況下能獲得超額利潤，但

6、也可能遭受虧損或不盈不虧，這取決于平均收益曲線ar與平均變動成本曲線savd的關系，如arsavc，則廠商有超額利潤或不盈不虧，如arsavc，則有虧損。這與完全競爭廠商實現均衡后的狀況比較是不同的，完全競爭是用價格p和平均成本sac來比較判斷的。 完全壟斷條件下，由于廠商即行業(yè)，它提供了整個行業(yè)所需要的全部產品，廠商可以控制和操縱市場價格，所以不存在有規(guī)律性的供給曲線，也無行業(yè)需求曲線和行業(yè)供給曲線，這些與完全競爭條件下是不相同的。 完全壟斷行業(yè)的長期均衡是以擁有超額利潤為特征的，這與完全競爭行業(yè)以超額利潤或虧損為零是不同的。完全壟斷廠商長期均衡的條件是：mrlmcsmc，這與完全競爭廠商長

7、期均衡條件相比，沒有mrlacsac。 與完全競爭相比，完全壟斷也不存在有規(guī)律性的長期供給曲線，這是完全壟斷形成的條件所決定的。 winger tuivasa-sheck, who scored two tries in the kiwis 20-18 semi-final win over england, has been passed fit after a lower-leg injury, while slater has been named at full-back but is still recovering from a knee injury aggravated aga

8、inst usa.both sides boast 100% records heading into the encounter but australia have not conceded a try since josh charnleys effort in their first pool match against england on the opening day.aussie winger jarryd hayne is the competitions top try scorer with nine, closely followed by tuivasa-sheck

9、with eight.but it is recently named rugby league international federation player of the year sonny bill williams who has attracted the most interest in the tournament so far.the kiwi - with a tournament high 17 offloads - has the chance of becoming the first player to win the world cup in both rugby

10、 league and rugby union after triumphing with the all blacks in 2011.id give every award back in a heartbeat just to get across the line this weekend, said williams.the (lack of) air up there watch mcayman islands-based webb, the head of fifas anti-racism taskforce, is in london for the football ass

11、ociations 150th anniversary celebrations and will attend citys premier league match at chelsea on sunday.i am going to be at the match tomorrow and i have asked to meet yaya toure, he told bbc sport.for me its about how he felt and i would like to speak to him first to find out what his experience w

12、as.uefa hasopened disciplinary proceedings against cskafor the racist behaviour of their fans duringcitys 2-1 win.michel platini, president of european footballs governing body, has also ordered an immediate investigation into the referees actions.cska said they were surprised and disappointed by to

13、ures complaint. in a statement the russian side added: we found no racist insults from fans of cska. baumgartner the disappointing news: mission aborted.the supersonic descent could happen as early as sunda.the weather plays an important role in this mission. starting at the ground, conditions have

14、to be very calm - winds less than 2 mph, with no precipitation or humidity and limited cloud cover. the balloon, with capsule attached, will move through the lower level of the atmosphere (the troposphere) where our day-to-day weather lives. it will climb higher than the tip of mount everest (5.5 mi

15、les/8.85 kilometers), drifting even higher than the cruising altitude of commercial airliners (5.6 miles/9.17 kilometers) and into the stratosphere. as he crosses the boundary layer (called the tropopause),e can expect a lot of turbulence.the balloon will slowly drift to the edge of space at 120,000

16、 feet ( then, i would assume, he will slowly step out onto something resembling an olympic diving platform.they blew it in 2008 when they got caught cold in the final and they will not make the same mistake against the kiwis in manchester.five years ago they cruised through to the final and so far h

17、istory has repeated itself here - the last try they conceded was scored by englands josh charnley in the opening game of the tournament.that could be classed as a weakness, a team under-cooked - but i have been impressed by the kangaroos focus in their games since then.they have been concentrating o

18、n the sort of stuff that wins you tough, even contests - strong defence, especially on their own goal-line, completing sets and a good kick-chase. theyve been great at all the unglamorous stuff that often goes unnoticed in the stands but not by your team-mates.it is as though their entire tournament has been preparation for the final.in johnathan thurston, cooper cronk, cameron smith and either billy slater or greg inglis at full-back they have a spine that is unmatched in rugby league. they have played in so many high-pressure games - a price