*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,第四讲,汇率决定理论,:,两个基本平价,1,一价定律,The law of one price,If two goods are identical,they must sell for the same price.,如果两种商品相同，应当按同一价格出售,2,考虑下列商品在中国和美国的销售价格：,周杰伦在伦敦的演唱会门票,西红柿,苹果公司的,Ipad2,房地产和理发,一价定律,The law of one price,3,非贸易品,Non-traded goods,(or,non-tradeables,)are items(usually services)for which interregional price differentials cannot be eliminated by arbitrage.,一价定律,The law of one price,4,A,(consumer)price index,is a weighted average of individual product prices,with weights determined by expenditure shares.,物价指数 price indices,5,物价指数 price indices,You open the newspaper one day to read these sensational headlines:,Price of salt to double!Petrol also up by 3%!,(100%+3%)/2=51.5%,？,(100%+3%+0%)/3=34.33%,？,6,Suppose weights of 0.1%for salt and 5.0%for petrol are found.Then the calculation is simply:,(0.001 100%)+(0.050 3%)=0.1%+0.15%=0.25%,物价指数 price indices,7,绝对购买力平价,Absolute,Purchasing power parity,P,i,=,SP,i,*,，,i,=1.,N,assume,the weights used in compiling the respective price indices are identical,P,=,SP,*,8,Proposition,：,The general level of prices,when converted to a common currency,will be the same in every country.,（,microeconomic view,）,Instead of the prices of individual goods and services being equated internationally,it is the general price levels themselves that are brought directly into the relationship predicted by PPP,（,macroeconomic,approach,)(also called,monetary model of,the exchange rate,),.,绝对购买力平价,Absolute Purchasing power parity,9,实际汇率,real exchange rate,The,real exchange rate,is the price of foreign relative to domestic goods and services.,Q,=,SP,*/,P,10,One countrys inflation rate can only be higher(lower)than anothers to the extent that its exchange rate depreciates(appreciates).,p,=,s,+,p,*,dp,=,ds,+,dp,*,dp,dp,*=,ds,相对购买力平价,R,elative,Purchasing power parity,11,考虑交易成本的相对购买力平价,P,=,K,(,SP,*),p,=,k,+,s,+,p,*,12,13,14,Purchasing power parity extensions,Traded versus non-traded goods:BalassaSamuelson,Trade costs and adjustment to PPP,qt,E,t,1=,f,(,Et,1,qt,1),zt,1(,Et,1,qt,1)0,f,1 1,15,Trade costs:iceberg model,PF,=,P,*,F,/(1 ),PC,=(1 ),P,*,Incomplete pass-through and pricing to market(PTM),Purchasing power parity extensions,16,Interest rate parity,17,