<p class="MsoNormal"><span lang="EN-US"><br/><!--Element not supported - Type: 8 Name: #comment--><op></op></span></p>

<p class="MsoNormal"><span lang="ZH-CN" style="font-family: SimSun;">在下目前在翻微观经济学的书</span><span lang="EN-US">,</span><span lang="EN-US"><op></op></span></p>

<p class="MsoNormal"><span lang="ZH-CN" style="font-family: SimSun;">里头的练习题想不出头绪¸麻烦各位指点了</span><span lang="EN-US"><op></op></span></p>

<p class="MsoNormal"><span lang="EN-US"><!--Element not supported - Type: 8 Name: #comment--> <!--Element not supported - Type: 8 Name: #comment--><op></op></span></p>

<p class="MsoNormal"><span lang="ZH-CN" style="font-family: SimSun;">以知条件</span><span lang="EN-US">, </span><span lang="ZH-CN" style="font-family: SimSun;">两物品的价格</span><i><span lang="EN-US">p</span></i><span lang="EN-US">= (<i>p</i>1,<i>p</i>2)</span><span lang="ZH-CN" style="font-family: SimSun;">和其间接效用函数</span><span lang="ZH-CN">
                </span><i><span lang="EN-US">v</span></i><span lang="EN-US">(<i>p,w</i>)</span><span lang="EN-US"><op></op></span></p>

<p class="MsoNormal"><span lang="ZH-CN" style="font-family: SimSun;">假设今天</span><i><span lang="EN-US">p</span></i><span lang="ZH-CN" style="font-family: SimSun;">价格下跌</span><span lang="EN-US">, <i>v</i>(<i>p</i>,<i>w</i>) = <i>v</i>(<i>p</i>`,w`)</span><span lang="EN-US"><op></op></span></p>

<p class="MsoNormal"><span lang="EN-US"><!--Element not supported - Type: 8 Name: #comment--> <!--Element not supported - Type: 8 Name: #comment--><op></op></span></p>

<p class="MsoNormal"><span lang="ZH-CN" style="font-family: SimSun;">第一个问题</span><span lang="EN-US">:</span><span lang="EN-US"><op></op></span></p>

<p class="MsoNormal"><span lang="ZH-CN" style="font-family: SimSun;">由于这公式</span><span lang="EN-US">w: w= <i>p</i>1<i>x</i>1 +<i>p</i>2<i>x</i>2, </span><span lang="ZH-CN" style="font-family: SimSun;">那</span><span lang="ZH-CN" style="font-family: SimSun;">么</span><span lang="ZH-CN" style="font-family: SimSun;">价格下跌表示</span><span lang="EN-US">w`
< w?</span><span lang="EN-US"><op></op></span></p>

<p class="MsoNormal"><span lang="ZH-CN" style="font-family: SimSun;">可是想想又不对</span><span lang="EN-US">, </span><span lang="ZH-CN" style="font-family: SimSun;">因为间接效用函数数值不变</span><span lang="ZH-CN">
                </span><i><span lang="EN-US">v</span></i><span lang="EN-US">(<i>p</i>,w)=v(<i>p</i>`,w`),</span><span lang="EN-US">
                        <op></op></span></p>

<p class="MsoNormal"><span lang="ZH-CN" style="font-family: SimSun;">那么</span><i><span lang="EN-US">p</span></i><i><span lang="EN-US">`</span></i><span lang="ZH-CN" style="font-family: SimSun;">下跌是代表</span><span lang="EN-US">w`</span><span lang="ZH-CN" style="font-family: SimSun;">上涨</span><span lang="EN-US">?</span><span lang="EN-US"><op></op></span></p>

<p class="MsoNormal"><span lang="EN-US"><!--Element not supported - Type: 8 Name: #comment--> <!--Element not supported - Type: 8 Name: #comment--><op></op></span></p>

<p class="MsoNormal"><span lang="ZH-CN" style="font-family: SimSun;">第二个问题</span><span lang="EN-US">:</span><span lang="EN-US"><op></op></span></p>

<p class="MsoNormal"><span lang="ZH-CN" style="font-family: SimSun;">假设后来才得知是</span><i><span lang="EN-US">p</span></i><span lang="EN-US">1</span><span lang="ZH-CN" style="font-family: SimSun;">的价格下滑</span><span lang="EN-US"><op></op></span></p>

<p class="MsoNormal"><span lang="ZH-CN" style="font-family: SimSun;">所以是</span><i><span lang="EN-US">p</span></i><span lang="EN-US"> = (<i>p</i>1,<i>p</i>2) </span><span lang="ZH-CN" style="font-family: SimSun;">变成</span><span lang="ZH-CN">
                </span><i><span lang="EN-US">p</span></i><span lang="EN-US">`
=(<i>p</i>1`,<i>p</i>2)</span><span lang="EN-US"><op></op></span></p>

<p class="MsoNormal"><span lang="ZH-CN" style="font-family: SimSun;">而且其直接效用函数</span><span lang="EN-US"> u(x) </span><span lang="ZH-CN" style="font-family: SimSun;">是严格凹性</span><span lang="EN-US">,</span><span lang="EN-US"><op></op></span></p>

<p class="MsoNormal"><span lang="ZH-CN" style="font-family: SimSun;">请问</span><span class="unicode"><span lang="ZH-CN" style="font-family: SimSun;">对于</span></span><i><span lang="EN-US">w</span></i><span lang="EN-US">`</span><span lang="ZH-CN" style="font-family: SimSun;">和</span><span class="unicode"><i><span lang="EN">p</span></i></span><span class="unicode"><span lang="EN">1` (<i>w`</i></span></span><span class="unicode"><span lang="ZH-CN" style="font-family: SimSun;">在上</span></span><span class="unicode"><span lang="EN">p1`</span></span><span class="unicode"><span lang="ZH-CN" style="font-family: SimSun;">在下</span></span><span class="unicode"><span lang="EN">)</span></span><span class="unicode"><span lang="ZH-CN" style="font-family: SimSun;">的一次导数跟二次导数各代表什幺意义</span></span><span class="unicode"><span lang="EN">?</span></span><span class="unicode"><span lang="EN"><op></op></span></span></p>

<p class="MsoNormal"><span class="unicode"><span lang="EN"><!--Element not supported - Type: 8 Name: #comment--> <!--Element not supported - Type: 8 Name: #comment--><op></op></span></span></p>

[此贴子已经被作者于2008-4-2 19:26:22编辑过]